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J Tiers
04-17-2019, 10:48 AM
Briggs 8FB, apparently low hours. Got it fairly recently for a low price. If will run, but not well.

Piston is very draggy in the cylinder. Moves more reasonably freely when moving, but if allowed to stop, has a peculiar stick-slip feeling that is unlike any other engine I have worked on. Does not like to idle, but runs OK otherwise. Engine is cast iron.

I suspect someone has been in the engine before, but I have no idea for what nor what they may have done.

So, No part seems different from other engines. Cylinder is clean, no gouges, original 2.250" size in unworn areas, not bored out to an oversize, has a few thou wear, mostly in the middle as one would expect, slightly egged. Piston looks good, rings are not carboned up, they are free, but ring slots are within spec, rings were installed correctly. Ring gaps are toward the replacement size, but still in spec. Rings not scuffed looking and appear to be correct.

Rod is good, not worn. Slight scuff in middle, but not too tight, oiling seems fine. Crank shaft rotates freely when piston is out.

Piston was hard to remove. Top and second ring do not ehow the stick-slip, they have the usual feel if they are the only rings in place. Oil ring alone, with no other rings, gives the stick-slip when moving the piston by hand. Ring and spring look good, are not in any way odd looking. I dosed it with lots of 30 ND down the plug hole when I got it, there is no lack of oil, dipper is good, nothing odd there.

My inclination is to just replace the rings, thinking that maybe the oil ring is just bad, but I cannot find any good reason why the oil ring should be that tight and odd-feeling.

Pics/ Cylinder pic looks worse at top than it is, there is no scratching when you look by eye, the camera seems to have picked up something and exaggerated it.

Anyone ever seen anything of the sort?

http://i.imgur.com/QnfTRsP.jpg (https://imgur.com/QnfTRsP)

http://i.imgur.com/3wecp7q.jpg (https://imgur.com/3wecp7q)

http://i.imgur.com/HiYWGin.jpg (https://imgur.com/HiYWGin)

RMinMN
04-17-2019, 10:58 AM
Slip the oil ring into the cylinder and use the top of the piston to be sure it is sitting level, them measure the end gap to see if the wrong oil ring was used. If it is too tight the end can be ground to give proper clearance.

Robg
04-17-2019, 11:34 AM
Looks like a fair bit of scuffing in the bore and especially on the rings. I suspect it ingested some dirty air from a defective air filter at some point - doesn’t take much for this to happen. New rings and a light hone in the bore should work fine assuming the bore to piston clearances are within spec.

J Tiers
04-17-2019, 11:53 AM
Ring gaps when checked that way were normal and even on the high side, getting toward the rejection limit, but not there yet according to the Briggs repair books I have..


Looks like a fair bit of scuffing in the bore and especially on the rings. I suspect it ingested some dirty air from a defective air filter at some point - doesn’t take much for this to happen. New rings and a light hone in the bore should work fine assuming the bore to piston clearances are within spec.

It's not anything like the pic, actually. The camera with flash picked up things that cannot be seen or felt when looking at/feeling the bore. What looks like scratching at the top cannot be felt, and can barely be seen, the bore is as smooth as silk all throughout, seems to have acquired the usual finish that they get. The spot on the right side in pic is barely visible, and is not feelable either.

And, as mentioned, it is only the oil ring that seems to be tight, but nothing shows up as out of the ordinary about it. Usually there is something that can be identified, but on this, there os nothing that seems out of the ordinary when looking at the thing.

Piston is about 14 under nominal, at 2.236, but I do not have a spec for the piston size. seems just a little small relative to what I usually see, but that seems not to be an issue, it all focuses on the (perfectly good/normal seeming) oil ring. I was even wondering if this engine uses the backup spring on the oil ring, I think some do not, although I do not recall which if any. That spring sure tightens up the ring.......

A.K. Boomer
04-17-2019, 12:05 PM
Two things - even if the pic makes things look allot worse im in agreement that the thing sucked at least a certain amount of dirt - there's allot of vertical lines,,,

the other concern and something that might verify your statement that "it looks like someone might have been in it before"
is the fact that it actually has horizontal lines, like someone gave it a hone WITHOUT knowing how to cross-hatch,,, you should never see horizontal lines there should only be 45 degree intercepting 45 degree's

horizontal lines will "catch" and esp. on something like an oil ring that has thinner edges and high unit pressures...

J Tiers
04-17-2019, 12:12 PM
That's an interesting point. I can give it a light hone, for sure. And then decide if the rings are out of spec.

A.K. Boomer
04-17-2019, 12:13 PM
And i would not reuse those rings - I would order up a new set - give it a "real hone" and assemble with some good break in oil and run that sow, dump the oil in short order and then go with some good quality lube done deal...

Those rings are shredded on their running surface JT, and the cylinder bore does not look much better - they stick because they are like velcro when they settle the oil film out...

Dave C
04-17-2019, 12:26 PM
+1 on what AK says. Someone didn't know how to hone a bore.

A.K. Boomer
04-17-2019, 12:30 PM
Slip the oil ring into the cylinder and use the top of the piston to be sure it is sitting level, them measure the end gap to see if the wrong oil ring was used. If it is too tight the end can be ground to give proper clearance.

Ring end gap is an all or nothing deal, it's never "just a little too tight" for if the rings ends actually grow to a point that they start to connect just a little then things snowball real fast as it becomes a slight press-fit and then creates even more heat and growth factor,,, ring end gap either "lives or dies" in short order and you generally will never see it on already worn rings, it usually happens right from the get go when someone rebuilds an engine and does not check it...

if you could straighten a ring out and then measure it's length then it's easier to understand as to why so much gap/room is needed to begin with and also why the expansion factor goes bazzerk if they ever did touch,,,

One time I got called in to do "forensics" on a freshly rebuilt Ferrari that ended up seizing within the first 50 miles of it's life, under very close examination I found evidence that all top comprendo rings had "fret marks" where they actually did grow to the point where they touched together, when I seen that I knew it was the engine builders fault and my report stated so...

Edit; there is an exception to what I just wrote, ring end gap can be on the ragged edge and still never give a whimper of trouble for thousands of miles, like if someone was babying their engine for a long period of break in time and then after so many miles decided to go out and pull a colorado summit at full throttle high RPM's and created a ton of heat in the process, now you can seize up long after the rebuild ...

Robg
04-17-2019, 12:49 PM
Be sure to check the wrist pin that it’s free and tight. New rings for sure and by all means be sure to use the expander behind the oil ring and any other ring if supplied with the ring set. The expander helps apply extra pressure to the cylinder (but not enough to cause binding). The oil ring controls oil retention on the cylinder wall & scrapes excess oil from the cylinder which will bypass the other rings and wind up in the combustion chamber resulting in high oil consumption.
The rings should float freely on the piston with no binding. Carefully clean the piston grooves for a free fit. Do this until the rings are in fact free moving. If not then piston replacement should be considered.
Obviously check ring end gap. A rule of thumb is .004” per inch of bore.

sarge41
04-17-2019, 01:04 PM
RMinMN beat me to it. It sounds like ring gap on the oil ring is the culprit. Just for curiosity, I would give the oil ring more end gap and check for stiction, then throw them away and follow AK's ideas.

Sarge41

A.K. Boomer
04-17-2019, 01:14 PM
If the oil rings end gap was actually so tight that it was dragging by hand turning of the crank it means the engine would not even be able to run at idle without complete seizure -
if end gap ever "connects" then you can consider it a press fit in short order, rings heat up along with pistons and combustion temps but if the ends ever touch then the rings heat goes supernova and snowballs and so does the expansion ratio, they either live - or seize there is no in-between...

MTNGUN
04-17-2019, 02:12 PM
If will run, but not well.

Valves, carb, ignition. Nothing wrong with freshening up the rings & cylinder as long as you have it apart but not likely to be a big culprit.

MattiJ
04-17-2019, 02:31 PM
Wrong oil ring/oil ring expander for that particular piston?
And sorry, can't think of clever way of measuring it except the extreme case where ring groove depth is same or less as expander+oil ring thickness combined.

chipmaker4130
04-17-2019, 02:55 PM
You guys keep coming back to ring gap, but Jerry says more than once that the gaps were checked and all were normal or even edging toward too big. He says the oil ring is somewhat tight, but NOT because of too little end gap, more like too much spring. Did I get that right, Jerry?

J Tiers
04-17-2019, 03:27 PM
Chipmaker: You are 100% on it. Gaps are spec 0.008 for new ring, these are setting up near 0.020 , rejection is 0.026 for the compression and 0.035 on oil ring, IIRC. so no possible way the gaps are causing trouble.

You saw the piston pic, so you can see there is no carbon, spec 0.005 feeler will not go in, nothing wrong there. Rings slide around fine, are not loose.

The engine is just not torn upthat badly. Most engines like it that I mess with have much more marking and scratching than that. Object is not a workhorse 20 year rebuild, but a runner that "works OK". I've got a bunch of engines, all sorts. I have several new ones to go through. Next one in line is a Briggs with the big C-shaped magneto core. After that a foot-start "Iron Horse", Then a Briggs "WB".

A hone won't hurt it, and it is a good point about the marks. I;ll give it a crosshatch and see how that goes. If I can still get rings, it will get them too, but my local engine shop closed up. And most of them are staffed by minimum wage 16 yo who only know how to put in the model and serial of the mower.....and all I have is the engine. Without that they have zero clue and say they can't help you.

I'll have to dig out my parts book and see if I can find the part no for the ring set.

A.K. Boomer
04-17-2019, 03:40 PM
You guys keep coming back to ring gap,


Not "me guys" im the one that was trying to steer everyone away from that flawed theory as it simply is not how things happen...

A.K. Boomer
04-17-2019, 03:49 PM
If the oil ring is really that tight I would take a serious look at the expander behind it - now that it seems the engine has been down before who knows if someone hodge podged it and used an expander from a different style oil ring and it's putting incredible pressure on the existing one, also, some expander ends are meant to "overlap" so they don't get into a pressure bind - check for how it was installed if you can remember,,,

J Tiers
04-18-2019, 01:01 AM
If the oil ring is really that tight I would take a serious look at the expander behind it - now that it seems the engine has been down before who knows if someone hodge podged it and used an expander from a different style oil ring and it's putting incredible pressure on the existing one, also, some expander ends are meant to "overlap" so they don't get into a pressure bind - check for how it was installed if you can remember,,,

No overlap, standard install. But I mentioned the question of whether it is even supposed to have the expander, because IIRC they do not all get the expander. The book mentions the expander in the terms of "if there is an expander ring". I I do not know, the parts book may show enough to determine that, IF it has the 8FB in it, which I do not know. My favorite (now closed) shop had about a 3 foot set of parts books, and always looked things up. The rest need every number from the mower its on or the computer can't find the parts.

If it did not have the expander as-built, that would make a lot of sense when it comes to the drag from the oil ring. If so, no clue why it was put in, unless a case of "it was in the kit". And no idea why it would be in there if it was not intended to be used. But looking at the piston, there is no extra space under the ring in that groove for an expander. I need to get at that parts book and check. The generic repair books just do not give enough information. the CDs don;t go back that far, and the parts book may be too old.

A.K. Boomer
04-18-2019, 01:09 AM
No overlap, standard install. But I mentioned the question of whether it is even supposed to have the expander, because IIRC they do not all get the expander. The book mentions the expander in the terms of "if there is an expander ring". I I do not know, the parts book may show enough to determine that, IF it has the 8FB in it, which I do not know. My favorite (now closed) shop had about a 3 foot set of parts books, and always looked things up. The rest need every number from the mower its on or the computer can't find the parts.

If it did not have the expander as-built, that would make a lot of sense when it comes to the drag from the oil ring. If so, no clue why it was put in, unless a case of "it was in the kit". And no idea why it would be in there if it was not intended to be used. But looking at the piston, there is no extra space under the ring in that groove for an expander. I need to get at that parts book and check. The generic repair books just do not give enough information. the CDs don;t go back that far, and the parts book may be too old.


Here's some "earmarks" you might be able to go off of then,,, look up your standard ring end gap for the engine (which I know you already have) now measure ALL your rings, comprendo - scraper and oil ring,,, (they all might have different specs) IF they all have worn at close to the same % rate increase from the original specs then it might lead you to assume that the oil ring was not too "out of control tight"

if the oil ring has worn a fair percentage over the others then it might make sense to conclude the opposite

it's worth a shot seeing as were having to shoot from the hip here...

J Tiers
04-18-2019, 01:28 AM
Here's some "earmarks" you might be able to go off of then,,, look up your standard ring end gap for the engine (which I know you already have) now measure ALL your rings, comprendo - scraper and oil ring,,, (they all might have different specs) IF they all have worn at close to the same % rate increase from the original specs then it might lead you to assume that the oil ring was not too "out of control tight"

if the oil ring has worn a fair percentage over the others then it might make sense to conclude the opposite

it's worth a shot seeing as were having to shoot from the hip here...

They are all about the same percent, I already checked the lot.

But the thing is low hours, original bore size at the ends, no heavy wear, no ridge. Probably not much info to be had there. And, I do not know if the thing is an assembly of more than one engine. The rings may not be from that engine, and could even be a set of 0.020 over rings or the like. The gap when open seemed large, but some are like that.

I can see very little reason for someone to have been into the engine if it is low hours, so they may have swapped in a good block and re-used parts from the worn engine. There's a lot unknown with any older engine.

A.K. Boomer
04-18-2019, 01:34 AM
Yup it's a "guess who's done it"


still - if the rings were .020' over and they adjusted end gap to correct you would see the extra ring tension (and more importantly wear) on the ends of the piston rings towards the gap - if they have a chamfer you would be able to visually confirm this,,, if they don't have a chamfer then measure them...

there really is no cheating here --- the forensics are right in front of you and you really should still be able to figure it out...

A.K. Boomer
04-18-2019, 01:48 AM
keep this in mind also - if it's a box stock ring set you will most likely be able to verify on the rings end gap ends,,, they will have that same black oxide footprint if never ground,,,

how many times have i ever had to adjust ring end gap from a standard issue replacement company or OEM? NEVER,,, iv checked to make sure but they always are withing specs,,,

now - high performance "dial in your own" ? totally different - buyer beware, you better check and in fact some of those companies are counting on it...

RichR
04-18-2019, 08:58 AM
According to the Briggs & Stratton site this manual covers your engine. It contains drawings and part numbers:
https://www.briggsandstratton.com/content/dam/briggsandstratton/na/en_us/Files/FAQs/Model%208-domestic.pdf

The manual was found here:
https://www.briggsandstratton.com/na/en_us/support/faqs/browse/antique-engine-specifications.html

J Tiers
04-18-2019, 02:37 PM
According to the Briggs & Stratton site this manual covers your engine. It contains drawings and part numbers:
https://www.briggsandstratton.com/content/dam/briggsandstratton/na/en_us/Files/FAQs/Model%208-domestic.pdf

The manual was found here:
https://www.briggsandstratton.com/na/en_us/support/faqs/browse/antique-engine-specifications.html

Thanks for the link. I guess they put up some stuff since the last time I looked, because I have another 8 series with a 400Hz alternator on it, and when I got it a number of years ago I looked for manuals and found nada. Thanks again.

I see there is no mention of a backup spring for the oil ring.... I do not know if that would have been simply assumed, or called out separately, but I would suppose they would have a separate part number for the spring, and scanning the list, I do not see it. Surely would explain a tight oil ring if this engine wasn't supposed to use the spring......

Pulled the crankshaft and cams etc, honed the bore. Can't seem to get a decent pic today. Forgot to look at the ring ends to see if they were "adjusted" at all. Whoever had their paws in it before may have decided to try to use an oversize ring set and "adjust it down" to fit.

Captain K
04-18-2019, 02:58 PM
Could be a twisted con rod. If it has insert bearing look closely at the back side, might show a couple shiny spots where is binding. Everything will move smoothly when checking parts individually but when assembled will bind.

J Tiers
04-18-2019, 03:31 PM
It was definitely associated with oil ring. And, looking at the rings, the two comp rings have black ends. The oil ring the ends are not, they are shinyish... too shiny for being stoned, but could have been filed. With that, and the possibly extra/non-OEM spring ring, it could account for the weird stickyness of the oil ring.

Honed the cyl. Do not want to change the bore size, so I stopped, but I may want to hit it a little more. The black streak I am not sure about, may be a bit of grease, didn't see it looking in when I took the pic. They are cutting up a fallen tree just outside this one of the shops and have the chipper going, so I quit before I went deaf.

http://i.imgur.com/YC9Stcq.jpg (https://imgur.com/YC9Stcq)

Jim Stewart
04-18-2019, 03:54 PM
A maybe-pertinent data point re ring expanders:

Twenty-some years ago there was a rash of seizures of two-stroke sportbike engines that were caused by the expansion ring breaking up and wedging itself behind the bottom ring. Two-stroke, so that wasn't an oil ring, but still...

Turned out that Niks pistons/rings from LA Sleeve had these failures (these were very popular pistons).

Now obviously your expansion ring is intact, but the reason I mention it is that the solution was to remove it. Many people did this and apparently nobody had any performance problems, leading to the question of "why". LA Sleeve's solution was to remove the expander ring from every piston box.

I was surprised to receive an email from Kevin Cameron asking about details of this failure. His opinion was that the expanders were there just to reduce noise. Hmmm.

So this suggests the same question for your engine: "why?" Since you've found the expander makes for a tight fit, leaving it out seems like a good idea, no?

-js

A.K. Boomer
04-18-2019, 04:41 PM
Nice pattern (crosshatch) JT.

Willy
04-18-2019, 05:01 PM
I've had a number of those engines on the bench over the years and much like yours the history was always an unknown. That being said I do remember that they all utilized a single piece oil control ring without an expander.
Not exactly sure what you have there and for me to guess would only be speculation. Maybe someone added it or more likely an aftermarket replacement, who knows?
However the style of oil control ring you show does often come without an expander.

http://www.smsenterprisesindia.com/wp-content/uploads/2017/10/structure3.jpg

Also I looked up the part # for a standard size oil control ring, as stated in the manual that was so graciously left here by RichR, and this Ebay listing shows the ring set having a single piece oil control ring without an expander.

https://www.ebay.com/itm/Antique-Briggs-And-Stratton-Piston-Ring-Set-290820-65451-61505-Model-A-M-S-Y/361903820017?epid=14012042178&hash=item5443260cf1:g:n9QAAOSwaB5Xuu18

And so does this listing.

https://www.ebay.com/itm/NOS-Briggs-Stratton-Piston-Ring-Set-290820-STD-Models-A-M-S-8-9/223472558851?epid=1738592750&hash=item340800a303:g:GPAAAOSwRbpcVaUB

J Tiers
04-18-2019, 05:49 PM
Thanks. I do not recall seeing a spring either. I do have a couple ring sets for a larger bore Briggs, and they DO have an expander, of the overlapped end style, so it could have gone either way.

J Tiers
04-18-2019, 06:55 PM
So, they turned off the chipper, and left, so I went back out to the shop.

Cleaned the cylinder triple super good, popped the old rings back on with no expander, oiled everything and stuck the piston down the spout. Surprise... it now slides pretty much like a piston should. I'd say it is a go, probably with new rings, although these do not seem too bad when looked at closely by eye. The camera seems to pick up on things that are not really visible.

J Tiers
05-01-2019, 07:08 PM
Substantial reassembly shows that leaving out the added backup spring, and having done a "glaze breaking" honing job, makes the thing spin like it should. No "stick-slip" like the way it was before.

When I get it back together I will see how it runs.

Dave C
05-02-2019, 12:15 AM
Good luck

J Tiers
05-02-2019, 01:02 AM
Good luck

Not sure if that was to have "chump" at the end of it, or not..... ;)

It ran before, it may run better now.

Dave C
05-02-2019, 10:58 AM
[QUOTE=J Tiers;1236134]Not sure if that was to have "chump" at the end of it, or not..... ;)

Chump? No way man. I'm all about turning a turd into a pearl. Nothing ventured, nothing gained. I hope it runs like a scalded dog.

J Tiers
05-02-2019, 11:56 AM
Ok.... Cool.

Thanks

J Tiers
05-16-2019, 02:30 PM
Had to clear the ebnch so this got reassembled and tested.

it will work, but the carb is messed up. Float valve is not shutting off fuel.

The angled jet will not come out, some prior owner made it into a "security screw" by ham-handedly rounding off the slot. This I discovered when I went to open it up. I DID get it apart, but the process of getting it back togther must have dislodged something.

Now I get the fun of loosening the jet when the slot etc is down in a 0.25" diameter hole about a half inch. I already know it is super tight. 2 piece Flo-jet, its the angled pipe that gos up and into the upper half after passing through the bottom half.

No, it shows ZERO corrosion, it is not an E10 problem.

Willy
05-16-2019, 04:15 PM
Is it just the needle and seat for the float system that you need to address or is the main jet circuit also suspect?
Just wondering why the main jet has to be removed, although it does sound like it has been "tickled" at some point and it or the nozzle leading to the venturi are needing attention.
Is the seat for the main needle still in good shape, as well as the needle itself?

Sounds like you're getting close, just a bit more of some unanticipated surgery.

J Tiers
05-16-2019, 10:24 PM
The float valve works, I tested it before re-assembly, and it shut off air blown into the fuel inlet, just from the weight of the very light float. But it does not seem to work when in place, at least in the crazy way it has to be done when the main jet does not come out.

Float is not gas-logged, it seems to be fine.

On the 2 piece Flo-Jet, the main jet is at an angle, with the needle coming out at an angle from the "corner" of the bowl. The pipe for it goes up at an angle thru the bowl casting, and into the top casting. That almost locks the two together, and the manual specifies (rightly) pulling the jet to get it apart.

I did very carefully get them apart without getting the jet out, but it involves a bunch of contortions that may have dislodged something when the same contortions are used getting it back together.

Carb is clean, no corrosion, no white dust, but the main jet is not coming out easily. Apparently this is not a new problem, because the P.O., or one of them, evidently tried to unscrew it and managed to round off the slot in the brass, like a security screw, so there is nothing whatever to get a "bite" on in the unscrewing direction. I soaked it with PBlaster, and tried carefully to unscrew it by twisting the pipe, but I could not grab that hard enough to get any real force on it without risking damage.

It will run for a little bit if gas is dropped into the carb inlet and the starter is pulled. Pops a few times and then is out of gas. So it has what it needs other than proper gas feed from the tank theu the carb. I put a little in and it ran out the weep hole in the carb inlet pipe (it is downdraft through the filter, then horizontal thru the carb).

lynnl
05-16-2019, 11:49 PM
Had to clear the ebnch so this got reassembled and tested.

it will work, but the carb is messed up. Float valve is not shutting off fuel.

.

I have a J. Deere (Mikuni carburetor) that had that problem at about age 22 or 23. It was fixed by putting in a new fuel inlet needle. The original looked perfectly fine on the business/seating end, but upon comparison with the new one it was obvious that a couple of thousandths had worn off the metal end that the float beared against, making it effectively too short.

J Tiers
06-04-2019, 11:51 PM
Finally got around to this project again, to get it off the bench so another one can go on (return of the Onan genset for reassembly).

Icould not get the main jet out of the carb, and you need to in order to get it apart or reassembled in a reasonable way (although it is just possible with the jet in place). I wanted to get it unscrewed, but a prior owner had chewed up the slot in the jet so it was basically a security screw, the unscrewing side was just a sloping ramp.

When I took it apart again, I found that the gyrations needed to get it together had let the float pin release one side if the float hinge, so it was just not working.

To get the jet out, so a sane process of reassembly was possible, I first tried a special screwdriver made to be held down by a fitting screwed onto the carburetor. The collar is held down by the brass cap so that the sloped damaged jet does not just let the screwdriver skid up the slope uselessly.

http://i.imgur.com/sv4GYFM.jpg (https://imgur.com/sv4GYFM)

it actually worked, I got the thing unscrewed a half turn. Then it jammed up again, and that time the remaining brass lugs simply sheared off of the jet, and it was game over on that approach. But it worked to begin with, and would have succeeded if the jet has not jammed solidly.

So, the next thing was to drill it out, which I did. It took all the tools in the pictures, including the pictured 1/4-32 tap which I luckily had already made for another carburetor problem.... Briggs seems to have liked that thread. Actually, there were several other drill sizes used, but those were just used for one quick pass each, getting the hole larger until the remainder was removed.

I drilled with the smallest drill, which followed the existing hole, then stepped up until the long tube was partly cut, and removed. Then I stepped up further, using the drill chuck shown, but by hand. First, the remaining part of the tube was cut loose, and pulled out, then part of the rest cut until it was nearly down to the threads. The tap was then run in, to clear the threads. drilling was done deeper, the tap used again, until the last part of the threaded jst tube came out. No significant damage to the caburetor body

Here are pics of the drills, chuck, tap, carb body, other needed tools, and the 3 remaining pieces of the jet. The tap removed some corrosion which presumably was what was locking the parts together. Now I get to source another jet.

What looks in the pic like white corrosion, is not. It is some sort of reflection. The bowl etc is all normal gray. There was just a little grayish corrosion in the threads, but it has the jet locked up solidly. I had soaked it several time with PBlaster.

http://i.imgur.com/C7dm5xO.jpg (https://imgur.com/C7dm5xO)
http://i.imgur.com/oEvsAyq.jpg?1 (https://imgur.com/oEvsAyq)

Bob Engelhardt
06-05-2019, 08:15 AM
... The collar is held down by the brass cap so that the sloped damaged jet does not just let the screwdriver skid up the slope uselessly.
...

Wait a minute ... how can the jet back out if the screwdriver is being held against it by the cap?

J Tiers
06-05-2019, 08:24 AM
Wait a minute ... how can the jet back out if the screwdriver is being held against it by the cap?

You leave a little space, and loosen gradually as you go. Ir was 32 tpi, not a fast thread.

Willy
06-05-2019, 10:50 AM
Congrats.
Although I don't go looking for it, I like when a well thought out surgery goes as planned. Something about the challenge and the hopefully successful outcome that makes it rewarding when it does go as planned. Taking care of the curve balls thrown along the way is all part of the game.

Running yet?:)

J Tiers
06-05-2019, 12:27 PM
Congrats.
Although I don't go looking for it, I like when a well thought out surgery goes as planned. Something about the challenge and the hopefully successful outcome that makes it rewarding when it does go as planned. Taking care of the curve balls thrown along the way is all part of the game.

Running yet?:)

Might have been if I had not needed to destroy the jet drilling it out. Would have been nice if the jet had not jammed up AFTER it was actually started on the way out......

When I get a new jet it may be working..... That was actually not the actual problem..... I should have a float valve in the parts collection, but they are obtainable. I hope THAT seat is as OK as I think it is, it holds air even with the existing valve "needle".

For now I have an Onan to put back together. Re-seated the valves, had to re-cut them, as I am not set up to grind valves at the moment. one was perfect as cut, the others needed a little grinding in place to get the thin ring contact Onan wanted on these.