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The Artful Bodger
12-24-2017, 12:52 AM
OK, the vehicle is a 1928/9 6 cylinder Dodge sedan which has overheating problems under some conditions.

The engine does not overheat pulling up hills, it does overheat when running freely on the flat.

Engine head gasket checked, water pump checked, new radiator ($$$!), fan/pump belt checked.

The owner says the engine never pinks(pings) but according to my recollection of such vehicles it should pink when under unnatural load such as opening the throttle wide in top gear when it should really be in a lower gear. He always drives with the ignition advance control fully advanced.

I suspect the ignition is too retarded and that causes the overheating....comments?

Anyone old enough to remember such things?

Thanks

John

10KPete
12-24-2017, 01:14 AM
Different car, but I had a '19 Ford T Touring that exhibited a similar symptom. It wouldn't heat quite enough to boil. Turns out that cracking the throttle a bit with the butterfly screw let enough extra air through to stop the issue. Then adjusted the timing and mixture to bring the idle back down. Problem solved!

Weird....

Pinging should be prevented whenever possible as it can damage piston/valves. Like your Dodge, the advance needs to be adjusted to the immediate conditions for best operation.

Pete

darryl
12-24-2017, 01:15 AM
I certainly remember. My Land Cruiser had what to me was an unusual vacuum retard system. Probably more related to the crude emissions controls that were just being mandated. Otherwise, engines had vacuum advance.

In your friends case, perhaps some experimenting would be in order, rather than just 'full advance' all the time. Perhaps also there's a misadjustment in the positioning of the distributor that actually requires that the advance control be set to full advance. Seems to me there should be a 'sweet spot' for that setting which would put it more towards the middle of its range. Then you'd have a bit more advance available- if as you say it seems too retarded now, that could help. Just guessing, I'm not a certified mechanic.

J Tiers
12-24-2017, 01:28 AM
I am presuming that it has no auto adjust, and the control is "it".

And I seem to recall that the engine can overheat from advance as well as retard, but that it takes a good bit of advance to do it. Does the control have the right RANGE? If it is shifted wrongly, it might never be able to be correctly adjusted.

Also, mixture might affect timing. Lean seems to slow the flame, so if it is lean, it might never "pink" (actually a great word for it, really), and lean can cause overheating.

With it lean, an all-the-time advance might bring it back to working kinda-sorta reasonably, but it would be compensating errors.

If the carb is over-rich when floored, then it might not "pink" on hills, due to rich mix.

Seems like a case where starting at the basics and going right through the tuneup might be justified.

Willy
12-24-2017, 01:46 AM
..................
...................
I suspect the ignition is too retarded and that causes the overheating....comments?

.....................

John

I suspect you may be correct. Retarded ignition timing can be a contributing factor to overheating. This in conjunction to a lean part throttle fuel/air mixture will will result in a delayed burn that is still well into the burn process going out thru the exhaust port and thus leading to increased heat input to the coolant. Full throttle application like under a heavy load would place the carburetor's main fuel circuit into play thus increasing the fuel to air ratio and fattening up the mixture to help mask the somewhat retarded timing's affect on overheating.

It would be ideal if the timing could be increased to the point of detonation (audible pinging) and than retarded to the point that it was no longer present. Try it there to see if the condition persists. Check also for carb jetting and intake/vacuum leaks as these are also contributors to the overheating situation.

I'm sure this this is strictly a manual timing control without the benefit of centrifugal or vacuum advance so it should be easy to change settings in order to find the sweet spot.

Willy
12-24-2017, 01:57 AM
I should have added that this is one of the vacuum advance units main benefits. It not only retards timing under load due to little to no vacuum signal, but it also advances the preset or centrifugal timing significantly under light load or part throttle conditions thus increasing fuel mileage considerably while reducing engine temperature input due to compromised (retarded) mechanical timing.

The Artful Bodger
12-24-2017, 03:35 AM
I have not taken a good look at the distributor yet but I expect it has a simple centrifugal advance mechanism and it almost certainly will not have vacuum advance.

Meanwhile the owner has managed to borrow a few bits to swap in including another radiator, pump and fan. It will be interesting to see what results if any.

boslab
12-24-2017, 08:08 AM
I would have gone with 1, thermostat stuck, 2, v absent 3 belt slipping 4 pump 5 too many radiator leak fix things, blocked cores in the radiator
The above have been the usual suspects so far with the exception of one head gasket, exhaust gasses getting into water ways caused an air lock type of thing stopping circulation, top hose was hot and stunk when removed
Very remote that ignition was to blame, it's usually the easy things first, took one pump off recently the impeller was eaten away
Mark

Seastar
12-24-2017, 09:23 AM
This may or may not be pertinate-----
I had an overheat problem with my air cooled 180 HP four cylinder aircraft engine.
The cylinder head temperatures would rise to above 425 DF when in normal level cruse power.
That's too high!
The engine has a dual electronic ignition system that has a complex advance curve.
The solution was to RETARD the spark system trigger by 3 degrees.
The cylinder head temperatures dropped to under 400 DF and became very balanced.
I am sure that the max takeoff power dropped slightly but it was unnoticeable.
Problem solved.
Bill

Machine
12-24-2017, 10:04 AM
OK, the vehicle is a 1928/9 6 cylinder Dodge sedan which has overheating problems under some conditions.

The engine does not overheat pulling up hills, it does overheat when running freely on the flat.
He always drives with the ignition advance control fully advanced.

I suspect the ignition is too retarded and that causes the overheating....comments?

First, make sure the radiator is not rusted or calcified up inside (by using well water which has minerals in it that deposit inside) so that you do not have proper coolant flow and heat transfer. Also make sure there are no leaves or other debris plugging up the air passages through the fins. And if this old car uses a thermostat, make sure it is installed and working properly.

Otherwise, from everything I ever knew about cars, ignition timing that is too far advanced is what will cause a car to overheat - NOT retarded timing. It also destroys pistons, rings and valves due to the extremely high pressures and temperatures involved with pre-ignition. You appear to confirm this by saying the owner always ran it "fully advanced" - but then you illogically conclude it's retarded. Why?

First thing I'd do is remove the distributor cap (unless it has a magneto ignition) and remove the spark plug from the number 1 cylinder. Verify that the ignition rotor (inside the dist cap) is pointing to the number 1 cylinder plug wire when the number 1 piston is at top dead center (make sure the points are opened as well to ensure you are on the firing stroke). Actually this is probably a flathead engine, so you may not be able to see the piston at TDC (or detect it using a narrow screwdriver dropped down inside). But you should be able to use a compression meter to detect compression as the rotor approaches the number 1 plug wire. The point of all this is to ensure the distributor has not been installed one gear tooth off and then rotated heavily into either a very retarded or advanced position to achieve basic firing timing again.

If you have a timing light, try checking the timing according to whatever the manual says. Although timing lights may not have existed back in the 1920's (I dunno). So I would put the number 1 cylinder at TDC, use a piece of chalk to put a mark on the flywheel or harmonic balancer or pulley (whatever it has) and also a mark on a stationary piece of something next to it (both chalk marks should be aligned. Rotate the engine back below top dead center (BTDC) about 4 degrees put another mark on the pulley and then again at 8 degrees BTDC. Then fire the engine up and see what the timing light measures. Most engines at idle run at about 2-4 degrees before TDC and advance up to about 8 degree BTDC at high engine speed. You can set it at 4 deg BTDC and take it for a spin. If it doesn't ping, advance a little bit at a time until it does ping...then back off a little. That's the old school way of setting timing. Although this car is so old it may have a manual ignition timing control on the steering column. In that case set the timing at 4 deg BTDC or 0 deg/TDC with the control in the centered position, and then experiment with different settings while driving around.

ahidley
12-24-2017, 12:59 PM
I didn't read all the suggestions so sorry if this was mentioned. The lower radiator hose should have a spring in it to prevent it from sucking shut (collapsing). If the spring rusted out or moved that can cause it

The Artful Bodger
12-24-2017, 02:23 PM
Thanks for all the comments.

It will be a few days before we can get back on to this project.

The Artful Bodger
12-24-2017, 02:55 PM
First, make sure the radiator is not rusted or calcified up inside (by using well water which has minerals in it that deposit inside) so that you do not have proper coolant flow and heat transfer. Also make sure there are no leaves or other debris plugging up the air passages through the fins. And if this old car uses a thermostat, make sure it is installed and working properly.

New radiator, no thermostat..




Otherwise, from everything I ever knew about cars, ignition timing that is too far advanced is what will cause a car to overheat - NOT retarded timing. It also destroys pistons, rings and valves due to the extremely high pressures and temperatures involved with pre-ignition. You appear to confirm this by saying the owner always ran it "fully advanced" - but then you illogically conclude it's retarded. Why?

If the ignition is over advanced I would expect it to pink under light loads but it does not. If the ignition timing is correct (and if my memory serves me right) the engine would pink when overloaded as in trying to accelerate in too high a gear, but the engine never pinks even though the owner keep the control fully advanced.



If it doesn't ping, advance a little bit at a time until it does ping...then back off a little. That's the old school way of setting timing. Although this car is so old it may have a manual ignition timing control on the steering column. In that case set the timing at 4 deg BTDC or 0 deg/TDC with the control in the centered position, and then experiment with different settings while driving around.

Yes, this car has manual ignition control.

Chris Evans
12-24-2017, 03:04 PM
In your part of the world do you have the dreaded ethanol added to the fuel ? It keeps the tree huggers happy but it buggers up the running of most old engines. On my late 1920s motorcycle engine I have made carburettor slides with differing cutaways to richen things up and retarded the ignition 4 degrees when on full advance. I marked the engine up accurately with a degree disc made marks for full advance at 35 instead of 39 degrees. Not running perfectly yet (will it ever?) but going in the right direction, when checking plug colour it now looks more like it should. It is definitely running cooler than before.

The Artful Bodger
12-24-2017, 03:19 PM
I do not believe we have ethanol in the fuel but I do wonder how petrol has changed over the last 80+ years.

J Tiers
12-24-2017, 04:36 PM
If the mix is rich, it may stay "cold" enough not to "pink". And, it is likely that the engine is low compression, by modern standards. The present gasoline usually has a rather high "octane" rating, so the combination may never pink for you.

The Artful Bodger
12-24-2017, 05:42 PM
That is true.

Machine
12-24-2017, 06:22 PM
One more thing - how do you know the car is overheating? Does it actually overheat and start blowing steam? Or do you have a gage that indicates overheating? Reason I ask is that sometimes a thermal sensor is either dodgy and intermittent for whatever reason or it can be positioned in a place that gets exposed to a trapped steam bubble that can make it read higher than the liquid coolant temperature actually is. Also, since you just replaced the radiator, what pressure is the cap you are using on the radiator? You gotta make sure it's rated at the right pressure so it doesn't blow off prematurely. I wouldn't know what it should be, but I would think a modern one should work well enough.

PS.. Oh yeah, make sure the fan blades are pointing in the right direction. I saw a guy once that managed to install his fan backwards so that it was pushing air through the radiator instead of pulling it through.

Machine
12-24-2017, 06:38 PM
If the ignition is over advanced I would expect it to pink under light loads but it does not. If the ignition timing is correct (and if my memory serves me right) the engine would pink when overloaded as in trying to accelerate in too high a gear, but the engine never pinks even though the owner keep the control fully advanced. Yes, this car has manual ignition control.

If it was over advanced the first place you would see "pinking" (what we call pinging here in the states) is in a heavily loaded condition. But if the engine is hot, and the timing is far enough advanced, it will ping in a lightly loaded condition too.

But you're saying the engine never pinks even though the manual timing lever is fully advanced and you're flooring the accelerator up a big hill. If that's the case, then like I said earlier, your distributor may be off by a tooth (there's a toothed gear that drives the distributor's shaft and it can be installed out of synch by one or more teeth) and/or your manual timing mechanism is not adjusted or installed properly and/or you have it all the way retarded instead of advanced and have mixed up the two timings (advanced vs retarded) based on the steering wheel mounted timing lever position. Check the basics. You should be able to make the engine ping, especially in the summer over some of those steep NZ hills. (and make sure your hearing isn't shot like mine is and you can actually hear pinging when it occurs)

Jim Stewart
12-24-2017, 07:31 PM
Ummm. This is a 1928 Dodge. Surely it didn't have a pressurized coolant system with a catch tank unless a hotrodder has been at it. When water gets hot it runs out the overflow onto the ground. And you add water every time you get gas.

Speaking of gas, if it's being fed regular gas that would be 89 octane in the US, or around 93 RON octane. I assume that engine is a flathead, probably has a compression ratio of around 5:1. Is it even *possible* to make it ping? Sorry, pink. The fuel it was fed in 1928 was (guessing) around 50 RON.

-js

Leadfootin
12-24-2017, 08:29 PM
Caution with ignition timing on these old low compression engines. Pinking is pre-ignition caused by something hot in the combustion chamber, often the spark plug tip or ground strap. Detonation however usually rears it's ugly head as a low pitched often very quiet grumble as it beats the nip out of the babbitt bearings and shortly thereafter fatigue fails the babbitt. Most of my experience is with pre-war Rolls-Royces (5:1 to 6:1 compression ratio) which when used regularly are extremely dependable and capable of very high mileage between rebuilds by using modern oils and filters. That said I own one where the engine was tired at 20,000 miles - never got out of Hollywood, a movie studio car. Another example is a club member who drives her Phantom III everywhere. She started a trend among PIII owners, if you get near Pikes Peaks climb it! Car easily made it to the top without pinking or grumbles.

One of the best skills to have around old cars is being able to read spark plugs. Every time I purposely push the engine to grumble via column ignition advance the plugs immediately show the little glassy balls of detonation on the insulator.

FYI most pre-war cars will run on old fuel, new fuel or just about any fuel which evaporates quickly and lights easily with a match, a trait shared with almost all of the pre-war cars excepting of a very few sports cars of the day.

sasquatch
12-24-2017, 08:36 PM
Engine pinging is usually caused by too far advanced ignition timing.

Jim Stewart
12-24-2017, 09:04 PM
Speaking of reading spark plugs: 40 years ago Gordon Jennings wrote an excellent piece in Cycle magazine. I was honored when he gave me permission to scan it and put it on my site.
https://www.strappe.com/plugs.html

-js

The Artful Bodger
12-24-2017, 09:10 PM
Ummm. This is a 1928 Dodge. Surely it didn't have a pressurized coolant system with a catch tank unless a hotrodder has been at it. When water gets hot it runs out the overflow onto the ground. And you add water every time you get gas.

Speaking of gas, if it's being fed regular gas that would be 89 octane in the US, or around 93 RON octane. I assume that engine is a flathead, probably has a compression ratio of around 5:1. Is it even *possible* to make it ping? Sorry, pink. The fuel it was fed in 1928 was (guessing) around 50 RON.

-js

Not pressurised, no expansion tank. Pump gas is supposed to be 92.

The Artful Bodger
12-24-2017, 09:15 PM
You should be able to make the engine ping, especially in the summer over some of those steep NZ hills. (and make sure your hearing isn't shot like mine is and you can actually hear pinging when it occurs)

What hills? I live on the Canterbury Plains and about 50 miles to the nearest hills!
http://static.panoramio.com/photos/large/34934103.jpg

lakeside53
12-24-2017, 09:44 PM
home... Except CHCH has hills nearer ;)

The Artful Bodger
12-24-2017, 09:53 PM
85kms to CHCH!

Willy
12-25-2017, 05:30 AM
..............

PS.. Oh yeah, make sure the fan blades are pointing in the right direction. I saw a guy once that managed to install his fan backwards so that it was pushing air through the radiator instead of pulling it through.

I'm not quite understanding how this could happen. In order for the fan to push air through the radiator instead of pulling air through it the rotation of the fan would have to be reversed. Simply installing it backwards would make no difference as to the direction of airflow.

I recently worked on a Dodge pickup who's owner complained of a noisy cooling fan. I though at first that it may have been a defective viscous fan clutch not releasing. Upon closer examination my first thoughts were that the fan looked somehow odd.
After removing the viscous clutch/fan assembly my suspicions were validated.
It was clear from the witness marks of the mounting holes plus the paint at the fan and clutch interface in conjunction with paint worn off of the fan blades by debris that this fan had left the factory 10 years earlier with it's fan installed backwards onto the fan clutch.
The clincher was that it also had stamped on it's backside, (this side to front).:)

The fan blew plenty of air rearward but due to the aerodynamics inherent to the blade's design it was clearly meant to be installed so that the leading edge entered the air stream first. Having the trailing edge enter first was very noisy and undoubtedly not as efficient.

big job
12-25-2017, 06:50 AM
Ya Im old enought = strange enought I have never heard one pinging cause they only about
5 or 6:1 compression. Timing light? back maybe 1940's early 50's those black bakelite
with a wimpy dull white flash, while new my ole man threw that across the shop. Even
today got no use for timing lights Use a Vac. gauge first choice. Next there should be two
adjustments on the distrubutor. (not sure on a 29 or 30) but in 1933 up set the top
adjustment the with pointer in the middle tighten screw, with the pulley on top dead
loosen bottom coller screw, move dist. left or right until points just start to open, that will
get you real close. Memory says points .020 now with vac gauge move dist and adjust
carbruator for highest reading on the gauge while at idle. Couple tic marks advance should
be fine. And then if the timing chain is stretched all is for not.. A lot of overheating was
caused by a weak or no thermostat. Should be 165 degree, if not with some the radiator
may not recover, it needs time to cool and recycle ..Flash back does anyone remember
a Chrysler Product comming along making a whooling noise? A common noise back in the
day; water pump time....

Jim Williams
12-25-2017, 09:56 AM
Most old cars have significant sediment in the engine water jacket, which will reduce cooling area, leading to overheating. The Vintage Garage in Stowe, Vermont has a number of pictures of Rolls Royce engines with about half of the water jacket obstructed with sediment. You may be able to get a look through the hose connections or removable plates if present.

brian Rupnow
12-25-2017, 10:21 AM
1-5-3-6-2-4 cylinder closest to rad is #1. Too much advance causes overheating

A.K. Boomer
12-25-2017, 11:24 AM
Did not read every post but enough to emphasis on some of the stuff already written, and as usually Willy's spot on with his fan diagnoses as they will still pull air the same direction regardless of how installed, but it's worth checking because they are designed with a "leading and trailing edge" that functions far better in one direction than the other,,,

anyhoo, retarded ignition timing creates more heat, and if it was too advanced you would hear major pinging - he does not - and since there are no audible "markers" for running retarded timing it is the first thing to check,

push it in the advanced direction to the point of "failure" or I should say pinging - then back off so many degree's till you don't hear it, what altitude is it at? it's 1 extra degree for every thousand feet till you get to 10,000 then you go half degree's (rough guide much depends on the engine and it's volumetric efficiency capabilities)

also - and someone did bring this up - too lean creates extra heat too, so when your "putzing" around you may be on a different carb circuit that does not give the correct ratio, then when you put your foot into it and open up the plate it starts dumping in a better ratio and cools the engine,,, this along with timing needs to be checked into,

this engine makes more power and yet creates less heat whilst doing it - if the RPM's are approximately the same while all this is going on you now have totally eliminated the cooling system as "being flawed" - the pump is pumping - the radiator is cooling and the fan is working ---------------------- soooooooooooo - that really only leaves two things to check into - ignition timing and carb mixture control throughout its range.... and don't forget - might not be just one or the other but a combination of the two...

flylo
12-25-2017, 01:16 PM
I agree if it doesn't ping under load going up hills stop "babying" it on the flats & see it it pings. AvGas in the '30s were 73 octane with lead. I had great luck mixing Marvel Mystery Oil in the fuel, never fouled a plug so I'd try that as you may have hot spots from hard carbon. To check for ethanol put water in a clear jar about 1/3 full & mark a line then add gasoline shake & let set & if the fuel/gas line changes you have ethanol.

Rich Carlstedt
12-25-2017, 01:47 PM
You need a vacuum gauge .
Then set timing using the vacuum

Rich

Leadfootin
12-25-2017, 02:41 PM
If you set the timing using a vacuum gauge use a timing light to verify the setting. Then you have a basu=is for further accurate adjustment.
I should have clarified earlier, aluminum block engines tend to rumble when detonating, pinging under pre-ignition. With iron blocks detonation will sound similar to pre-ignition just not as sharp a ping.

Willy
12-25-2017, 04:56 PM
Good points. One must remember also that tune procedures and operational characteristics are not what most folks think of when doing a tune-up.
Things like a vibration damper with timing marks or even a mark on a flywheel probably won't be there in order to even use a timing light and as mentioned cooling systems were also much more primitive than what we take for granted today. These engines were introduced shortly after the use of thermosyphon cooling systems were in widespread use.
Rudimentary tune-up procedures are what works best and is all that is needed. These things don`t need to be setup within a gnat`s whisker of of their life in order to be perfectly functional and reliable.

I think the the OP has had plenty of experience already in restoring and maintaining older working examples of mechanical history to realize all of this.

Some good insight by Leadfootin.
Most folks use the terms detonation and pre-ignition interchangeably.
The two combustion event anomalies are very distinct phenomena with different roots of origin. Although not as prevalent in low compression engine designs they can most certainly occur under the right (wrong:)) conditions.

CarlByrns
12-26-2017, 08:24 PM
Before you do anything, verify the temp gauge is working correctly!

The Artful Bodger
12-26-2017, 08:46 PM
Before you do anything, verify the temp gauge is working correctly!

Good point but considering it is requiring more water than petrol I do believe something is wrong.

Rich Carlstedt
12-26-2017, 11:11 PM
I know I mentioned a Vacuum gauge earlier but.....
Those old engines had to have a cooling system / radiator cleaning once in a while.
Then I would use some antifreeze instead of straight water.
Also need to pull a plug on # 1 and use a stick to see if the timing mark on ( TDC )the vibration dampner is correct !
I really suspect a intake manifold leak which changes the fuel ratio on some cylinders !
Spark ping sounds like marbles rolling around
Rich

A.K. Boomer
12-26-2017, 11:27 PM
I know I mentioned a Vacuum gauge earlier but.....
Those old engines had to have a cooling system / radiator cleaning once in a while.
Then I would use some antifreeze instead of straight water.

his cooling system is ample - its getting the job done under the most load and if it's the same speed and in the same gearing that means its the same air flow past the radiator and coolant flow to the cores so if it cools under full load it would have no problem cooling when backing off


Also need to pull a plug on # 1 and use a stick to see if the timing mark on ( TDC )the vibration dampner is correct !
for sure -providing this thing even has a vibration dampner - if not just verify or even make your own mark with the method you described


I really suspect a intake manifold leak which changes the fuel ratio on some cylinders !

this is a damn good thought - but anything substantial enough to cause overheat problems in mild running is going to totally raise hell with an idle... I think he would have mentioned this...

The Artful Bodger
12-27-2017, 12:30 AM
I think the radiator will be quite clean as it has only recently been manufactured.

The timing mark is on the flywheel.


Good point about the intake manifold leak especially as the engine tends to run hot when in conditions of highest manifold vacuum, thanks.

Leadfootin
12-27-2017, 07:03 AM
To find a vacuum leak use a piece of fuel line held close to the ear and put the other end near any suspected leak areas. Another trick used by the Bentley / Rolls crowd is an unlit propane torch near suspected leaks, the idle will speed up. However this method is somewhat risky for obvious reasons.

Personally I would set the timing by peak vacuum reading at idle, backing down about an inch if unstable. Some engines tend to hunt, that is speed up and down slightly if the timing is too advanced at part load.

CarlByrns
12-27-2017, 07:28 AM
Good point but considering it is requiring more water than petrol I do believe something is wrong.

Do you have a <water loss> problem or a <high temperature> problem? They're not the same thing- the engine could be losing water due to a leak and overheating or it could be overheating and causing water loss due to boilover.

Stepside
12-27-2017, 09:04 AM
In 1960 I had a new to me 1948 Plymouth. It was running poorly and I checked the plugs, plug wires, timing and all seemed to be satisfactory. A mechanic friend of my father stopped by and took a look at my problem.

The sequence of events went like this. 1) start the car 2) turn off the blankety blank radio and heater fan 3) he reached over and put side pressure on the air cleaner and said "listen". You could hear the engine speed change as he pushed or pulled on the air cleaner. He then helped me rebuild the carburetor as it had a damaged gasket between some of the parts. The damage was caused by loose screws that held it together.

CarlByrns
12-27-2017, 10:20 AM
Here's another thought: has anyone inspected the exhaust? A lot of waste heat is carried off by the exhaust gases and a kinked or crimped pipe (or plugged muffler) will cause overheating.

Tim Clarke
12-27-2017, 03:58 PM
So. Back in the dark ages, I rebuilt a couple old Dodge engines. Built pre-WWII. One because of overheating. Owner was sure there was a crack somewhere. We tore the thing down hot tanked it, then did the magaflux crack inspection, finding no cracks. Old George came around and asked if I had pulled the water tube. Huh? Say what? He showed me there was a sheet metal water distribution tube behind the water pump. I pulled it out with a pair of pliers, and sure enough, about 2 cylinders worth was rusted off the far end. At the time, you could get them from the Carquest auto parts stores.

Better get the pump off and see what you have. They're almost as long as the block, so you're going to need to pull that shiny new radiator, I think.

CarlByrns
12-27-2017, 04:17 PM
So. Back in the dark ages, I rebuilt a couple old Dodge engines. Built pre-WWII. One because of overheating. Owner was sure there was a crack somewhere. We tore the thing down hot tanked it, then did the magaflux crack inspection, finding no cracks. Old George came around and asked if I had pulled the water tube. Huh? Say what? He showed me there was a sheet metal water distribution tube behind the water pump. I pulled it out with a pair of pliers, and sure enough, about 2 cylinders worth was rusted off the far end. At the time, you could get them from the Carquest auto parts stores.

Better get the pump off and see what you have. They're almost as long as the block, so you're going to need to pull that shiny new radiator, I think.

That makes sense. A lot of inline sixes had them back in the day.

The Artful Bodger
01-01-2018, 03:06 AM
Progress report:-

The car will be going on long trip (150 miles or so) in a day or so. There has been a bit of work done to an ill fitting radiator cap.

I have asked the owner to take particular not of under what conditions does the temperature rise.

More information in a day or three!

Robg
01-01-2018, 01:17 PM
When it's at operating temp, engine off, feel the rad all over. If there is any restriction you feel cool spots - an easy double check.
There should be a thermostat in it, if not the coolant circulates too quickly & doesn't absorb and carry off the heat. Put the t-stat in the right direction. Do not run without one.
Check for vacuum leaks. Get some spray carb/brake cleaner even a spray bottle with water. Engine running, spray around all fuel intake areas - carb base, manifold to head, etc. There will be a change in idle rpm if there is a vac leak. A vacuum leak will cause an overheat problem because of a very lean fuel mixture.
Timing - too retarded and performance will be sluggish. Too advanced will be ping. If you don't have a timing light or are unfamiliar with it do this:
- Get TDC (Top Dead Center) on #1 cyl COMPRESSION stroke.
- Bring the vibration damper timing mark to what the timing should be set to. Start with about 6 degrees Before Top Dead Center.
- Loosen the distributor hold down so it turns with a bit of friction.
- Turn ignition key on but NOT start.
- Remove #1 plug wire & hold !/4" or so from ground.
- Rotate the distributor until a spark jumps to ground. Stop rotating (:-}) right when the spark jumps. No further.
- Timing is now set to wherever you lined up the timing marks on the vibration damper.
- Tighten the distributor hold down.
Hope this helps.

brian Rupnow
01-01-2018, 02:06 PM
Take the rad cap off and look down inside. I had an old car one time that I decided not to drive in the winter, so I took the rad cap off and opened the drain to drain all the engine coolant. I left the rad cap setting on top of the air cleaner and shut the hood. Damned mice found an old mattress somewhere and had half of the stuffing dragged down into the top of the rad to make a cozy nest for the winter. I had a terrible time getting it all out.

The Artful Bodger
01-01-2018, 02:15 PM
Brian, not this time, it is a new radiator.

BTW, we had a plane visit us at an island where we were living at the time (19S 169W). The plane was a HS748
http://rzjets.net/images/operators/987.jpg

It was on the ground for only an hour but when they went to take off several instruments were not registering as mason bees had been busy 'patching' the pitot heads and static ports!

lakeside53
01-01-2018, 07:57 PM
I flew Jump seat from Auckland to CHCH on one those.

Arcane
01-02-2018, 07:07 AM
.......There should be a thermostat in it, if not the coolant circulates too quickly & doesn't absorb and carry off the heat.......

Sorry, but this is a myth that just keeps circulating...

A.K. Boomer
01-02-2018, 09:32 AM
I still do not know why where subjecting the cooling system to such scrutiny --- the cooling system works remember - it's cooling the engine under maximum load...

Robg
01-02-2018, 06:06 PM
Sorry Arcane, I don't know what proof you have of running without a thermostat being a myth. The cooling system is for removing excess heat but it is also more important to bring the engine up to operating temperature as fast as possible where is it will run most efficiently and reduce emissions. On computer controlled vehicles the major management systems don't function on a feedback stage until a certain temperature level is reached. Even older (vintage) vehicles have other systems to warm up the engines more quickly than the cooling system such as the heat riser to warm the intake manifold to improve vaporization of the air-fuel mixture at cold start up.
Granted, you can run without a t-stat and if the outside temperature is moderate things will still operate seemingly ok. However, why would you? Even older non-computerized vehicles will still suffer lower fuel economy, lower performance, build up internal engine sludge faster and excessively, and pollute more.
All engines are meant to operate at optimum temperatures first & foremost and the manufacturer has gone to a great deal of engineering to achieve this.

Willy
01-02-2018, 06:52 PM
I think what Arcane meant was that it is a myth that running without a thermostat will lead to overheating due to the coolant not having time to absorb the engine's excess heat. No thermostat in the system would mean that the cooling system is operating at maximum heat rejection capacity. Much like it would on a very hot day under heavy load. Most of the time a thermostat is open only partially or open only briefly.
Everything that I have seen both personally and in factory service manuals suggests that engine operation without the use of a thermostat leads to over cooling.

While I can't show that evidence here I can point to a citation from a Gates cooling system troubleshooting manual.

https://www.gatesaustralia.com.au/~/media/files/gates-au/automotive/catalogues/cooling-system-troubleshooting-manual-ausnz-april-2015.pdf

Top of page 19.


Scenarios for thermostat failure
Thermostats, like any other part, don’t last forever. There are two scenarios
for failing thermostats:
1. If the thermostat becomes stuck in the open position, there is continuous flow
of coolant into the radiator causing the engine to run cold. Overcooled engines run
inefficiently, which leads to increased fuel consumption and higher emission levels
and engine parts enduring more wear. In addition, the car interior will not heat up
properly.
2. If the thermostat becomes stuck in the closed position, the circulation of the
coolant is blocked so the coolant cannot get to the radiator to be cooled which
causes the engine to overheat.

However I totally agree to your other points about the importance of using a thermostat. Removing one is a nicht-nicht in my book.:)

Jim Stewart
01-02-2018, 07:23 PM
Are we sure that this 1928 Dodge had a thermostat originally?

-js

Willy
01-02-2018, 07:28 PM
I'd be very surprised if it did. Like I mentioned earlier these were relatively crude cooling systems just one step above thermosyphon cooling systems used just a few years earlier.


Edited to add: The OP stated in post #13 that the car has no thermostat.

The Artful Bodger
01-02-2018, 07:39 PM
I will see what the owner has to report after his trip away in the vehicle but I do not think the problem can be described as a cooling system issue, more like the engine producing more heat under certain circumstances.

As far as I can deduce the excessive heating occurs when the vehicle is running freely on the flat which I expect is the time when the manifold depression is at its maximum. There is no vacuum advance on the distributor leading me to suspect (based on comments by others here) either ignition retarded or air leak(s) causing lean mixture.

Time will tell.

wombat2go
01-02-2018, 08:15 PM
According to this, the wax thermostat was invented in 1936.
https://en.wikipedia.org/wiki/Wax_thermostatic_element
(I think there are obvious typos in the first paragraph dates.)

So if the New Zealand engine is a 1928 Dodge Victory six, it would not have had one

It must have been tough in places like here in Michigan when the temperatures are in the negative Fahrenheit.
Then the same cars were sent to Arizona and Australia/New Zealand etc for the other extreme.

Leadfootin
01-02-2018, 08:23 PM
I have encountered many an alcohol filled bellows thermostat or on shutters a calorstat. Even found one on a 1959 Massey tractor! Rolls-Royce used the alcohol filled bellows for many years and there are still craftsmen who will repair or rebuild them as needed. Both my 36 and 38 Phantom III's have them to operate the rad shutters.

Arcane
01-02-2018, 08:56 PM
Sorry Arcane, I don't know what proof you have of running without a thermostat being a myth. The cooling system is for removing excess heat but it is also more important to bring the engine up to operating temperature as fast as possible where is it will run most efficiently and reduce emissions. On computer controlled vehicles the major management systems don't function on a feedback stage until a certain temperature level is reached. Even older (vintage) vehicles have other systems to warm up the engines more quickly than the cooling system such as the heat riser to warm the intake manifold to improve vaporization of the air-fuel mixture at cold start up.
Granted, you can run without a t-stat and if the outside temperature is moderate things will still operate seemingly ok. However, why would you? Even older non-computerized vehicles will still suffer lower fuel economy, lower performance, build up internal engine sludge faster and excessively, and pollute more.
All engines are meant to operate at optimum temperatures first & foremost and the manufacturer has gone to a great deal of engineering to achieve this.

You stated:
There should be a thermostat in it, if not the coolant circulates too quickly & doesn't absorb and carry off the heat

The myth part is "the coolant circulates too quickly & doesn't absorb and carry off the heat". This has been proven false decades ago, likely by many companies, but the one I first saw who offered definite proof it was a myth was a company that built water pumps (and radiators also IIRC) for race cars. They built a complete testing system that measured flows, temperatures, pressures and horsepower consumed and they stated that their tests showed that the statement "the coolant circulates too quickly & doesn't absorb and carry off the heat" was 100 % false.

Willy correctly summarized what happens without a thermostat in an engine, but another thing that a thermostat does is provide a restriction to the water flow which raises the pressure of the coolant inside the block. This increase in pressure prevents steam pockets from forming quite as easily. Steam transfers heat very poorly compared to coolant. Some people who aren't concerned about warm up times ( think Stock Cars) sometimes will use restrictors (basically a plate with a hole in it that flows the same as a thermostat) instead of thermostats to eliminate any chance of a failed thermostat.

A.K. Boomer
01-02-2018, 09:26 PM
People get mixed up - while the coolant that's traveling faster may not leave the engine block hotter (and in fact it won't) they forget the gallons per minute factor and even though the discharge temp is way lower the overall BTU exchange is far greater

there's one exception --- make the water move so fast that it starts creating its own heat/friction

but not to many water pumps capable of this as they would be eating up dozens of hp in the process...

wombat2go
01-02-2018, 10:06 PM
As A.K. mentions, main purpose of the thermostat is to reduce the coolant flow ( Gal per min or litre per minute).
This reduces the flow of heat out of the radiator to the cooling air.
In a pressurized system ( which the old Dodge probably is not), the water gets hotter and the pressure rises.
this raises the boiling point and raises the temperature at which nucleation boiling might occur.

As Arcane mentions, nucleation boiling leads to steam pockets resulting in higher metal temperatures in cylinder head etc.

In Australia in '50 ~early 60's the cooling systems were pressurized by the spring in radiator cap.
But there was no collection ( The radiator cap had only a seal under the spring)
So it was common on a hot day for the cars to come in the driveway for petrol ( gasoline)
and switch off which was followed by "running on" clatter and dumping of coolant.

The addition of glycol to water as coolant is necessary for antifreeze, but it reduces the
thermal conductivity of the turbulent coolant by 5 ~ 20% depending on concentration.

In induction heating, the heat flux to liquid coolant may be 5~ 10 times that of automotive,
so if the water flow falls out of turbulence,
the nucleation boiling ( steam pocket) often results in an explosion of the inductor -molten copper.

J Tiers
01-03-2018, 12:01 AM
The faster flow scrubs off the boundary layer of hot water and brings in cooler water to replace it. Air cooling is always better at faster flows (within reason) and in general the same is true with water cooling.

Only if the flow rate is large enough to cause other issues does that general rule break down.

Cooler 'coolant' leaving gives better heat transfer, due to the larger temperature differential from hot thing to coolant..

aostling
01-03-2018, 02:05 AM
What hills? I live on the Canterbury Plains and about 50 miles to the nearest hills!
http://static.panoramio.com/photos/large/34934103.jpg

Ah, the Rakaia, looking NW to Windwhistle. Nice photo, if you took it. I always get lost on the Canterbury Plains.

The Artful Bodger
01-03-2018, 02:07 AM
Ah, the Rakaia, looking NW to Windwhistle. Nice photo, if you took it. I always get lost on the Canterbury Plains.

Sorry Allan but not my photo.

John

The Artful Bodger
01-05-2018, 02:53 PM
The owner of the car did not get to do his trip away due to factors unrelated to the vehicle.

However he did swap in another radiator borrowed from a friend and the car performed faultlessly on a few shorter runs.

Now there are three radiators in the picture, number one is the one that was in the car when he bought it, number two is the copy made of that radiator when the first was judged to be plugged, number three is the borrowed radiator. I have not seen number one (the original radiator) but I was able to compare number two (the new radiator) with number three (the borrowed radiator). Number three is noticeably different in that each airway seems to have some sort of internal fins whereas number two is a clear view right through the radiator. It remains to be seen if number two is an accurate copy of number one.

Regarding the myths and such related to excessive fast water flow. We have observed that water flow through the new radiator is such that water flows so freely that it can all go down just a few of the passages leaving the edges of the radiator practically unused. Debate now includes what can be done about that including baffle plates in the header tank.