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View Full Version : Cylinder blockface repair - another JBweld question



Timleech
03-24-2011, 09:58 AM
Reading the JBweld thread led me to thinking about a job I have on at the moment. 6-cyl diesel, one-piece head. It blew head gasket 4 years ago. I had the head skimmed, cleaned up the top of the block but it's not good. Fitted head with new joint + some high-temp jointing (Loctite product IIRC, can't remember which). Told the owner not to expect miracles, he was planning to sell the boat while the going was good.
4 years down the line, he still has it & it's blown the gasket again between two cylinders. Block really needs refacing, but that's quite a big engine-out job, not practical at present and may cost more than the boat is worth.

So.....is there any magic metal compound which could be used on the block face to build it up, which has a good chance of extending the life?

I have Belzona 1111 to hand, but I wouldn't expect any of these epoxy-based compounds to last very long where they're in contact with the combustion space, even if it's only a very thin 'edge' which is in contact initially. Maybe I'm being too pessimistic?

Thanks

Tim

topct
03-24-2011, 10:50 AM
Maybe something like this,

http://www.alvinproducts.com/Products/Products.asp?ID=2

That and a solid copper head gasket? Or an aluminum one?

strokersix
03-24-2011, 11:07 AM
If it's a small groove between cylinders you could fill it with a stitching pin or several, peen and file it smooth. Lock n stitch is one brand. If you don't want to buy stitching pins you could use small screws instead. Assuming this block is automotive type design you only need a decent surface at the gasket fire ring, fill the rest with something easy like RTV or your favorite magic sealant.

justanengineer
03-24-2011, 12:33 PM
Depending on the situation, I have had good luck in the past simply by using a thicker head gasket.

hardtail
03-24-2011, 12:52 PM
Belzona is usually a pretty good product if that particular one is for a filler type of repair for heat......my buddy had good success doing a Jaguar 6 cyl engine but it was a gasser so the combustion pressures are lower.......sounds like theres an inherant problem with that design......if the original isn't cutting it may be hard to expect any miracle cure to but I would offer the hail Mary to the owner vs removing that block for decking......with no guarantees.

The real hazard here may be coolant leaking back into the cylinder and crankcase if theres a passage near the leak as the engine cools every time it's used and emulsufication damaging the bearings.......maybe thats not the case?

Maybe this time he'll sell it?

Steve Steven
03-24-2011, 12:54 PM
I had a Astre (Vega in Pontiac clothes) with a similiar problem, undercut head surface at top of the cylinder on the water jacket side, little surface for the gasket to seat on. The car was old and not worth putting much into.

I made a light skim cut on the damaged area with a Dremel to get good metal, and used steel filled epoxy to build up a area approximating the missing metal. Used a file to get the surface flat.

It held for the remainder of the time I had the car, about a year or so.

Steve

vpt
03-24-2011, 01:23 PM
What about lead? Torch it in and file flat.

steverice
03-24-2011, 01:44 PM
take the motor out, surface the block and do it right - if not you will be back here in a couple more weeks asking the same question.

Timleech
03-24-2011, 02:31 PM
Belzona is usually a pretty good product if that particular one is for a filler type of repair for heat......my buddy had good success doing a Jaguar 6 cyl engine but it was a gasser so the combustion pressures are lower.......sounds like theres an inherant problem with that design......if the original isn't cutting it may be hard to expect any miracle cure to but I would offer the hail Mary to the owner vs removing that block for decking......with no guarantees.

The real hazard here may be coolant leaking back into the cylinder and crankcase if theres a passage near the leak as the engine cools every time it's used and emulsufication damaging the bearings.......maybe thats not the case?

Maybe this time he'll sell it?


No, it's blowing between cylinders, it's a fairly narrow land between them and of course a bit more of it gets eroded each time a gasket blows.

The new gasket is having to be specially made in solid copper, previously it's been old stock copper/as**stos but no more are to be found (it's a 1954 engine). That might give it more of a chance than the composite gasket.

No, as I've already said, taking the engine out and stripping it to do the job properly is NOT an option at this stage.

Thanks

Tim

airsmith282
03-24-2011, 02:49 PM
iam not for any sort of epoxy soloution for this so you got 2 options, take out the motor and do it right or, use HTS-2000 that can also fix it properly

do not melt lead in its not going to hold for more then 20 min or so then youll be back where you started...

JCHannum
03-24-2011, 02:58 PM
It might be worthwhile contacting Belzona for their recommendations. The 1111 might be applicable, but temperature resistance is on the low side. It would depend to a degree on how thick the application is. The copper gasket might work to your advantage.

http://www.belzona-bsn.de/downloads/1111ps.pdf

Timleech
03-24-2011, 03:02 PM
iam not for any sort of epoxy soloution for this so you got 2 options, take out the motor and do it right or, use HTS-2000 that can also fix it properly

do not melt lead in its not going to hold for more then 20 min or so then youll be back where you started...

Never heard of HTS2000 before, just googled it & it's an aluminium 'brazing' alloy. This is a cast iron block, are you suggesting it would work or just guessing it's an ali block?.

Tim

hardtail
03-24-2011, 03:48 PM
If it's a fresh copper gasket great if not it will need to be annealed.......other have found success with giving an old gasket a light coat of aluminum rattle can spray, others yet aviation permatex.......but since the area has been under attack previously and now again I have a feeling the gasket is toast for sure.....if there is any chance combustion flame will touch the lead I think it would just melt out. Either way the gasket is just to seal 2 good mating surfaces and missing parent material will have to be replaced by something. The Jaguar repair was in a similar area as this engine.....this engine have seperate firerings or just the gasket?

DICKEYBIRD
03-24-2011, 03:50 PM
Seems to me that if the land between the cyl bore is narrow, the expansion & contraction from heating/cooling plus diesel hammering would fairly quickly cause any sort of epoxy/magic compound to crack loose and erode away.

Is Tig welding or brazing a possibility followed by a bit of dressing of the area with a die-grinder and a nice new flat file?

How many cylinders does it have? Can you jerk the 2 injectors from those cylinders and just say it's the all new for 2011 Green Edition that burns less fuel than the old 1954 model?:D

form_change
03-24-2011, 03:52 PM
It's a bit out of the ordinary, but could you build up the area using a metal spraying technique? It might give enough build that a gasket is properly supported.

Michael

doctor demo
03-24-2011, 03:54 PM
I once welded up a burnt spot in an auto V-8 block between cylinders in the car. I used a buzz box and Ni Rod, then filed it flat. The repair was working years later when the guy sold the car.

If You try welding it and it doesn't work, You are only out a few bucks for the rod and a little time...it isn't any good the way it is now.
The lock pin method mentioned earlier might be a decent option to look into.

One other not very practical option would be to hand scrape the block flat, but I would only use that as a last resort.

Steve

Timleech
03-24-2011, 04:09 PM
I once welded up a burnt spot in an auto V-8 block between cylinders in the car. I used a buzz box and Ni Rod, then filed it flat. The repair was working years later when the guy sold the car.

If You try welding it and it doesn't work, You are only out a few bucks for the rod and a little time...it isn't any good the way it is now.
The lock pin method mentioned earlier might be a decent option to look into.

One other not very practical option would be to hand scrape the block flat, but I would only use that as a last resort.

Steve

That did cross my mind a while ago, but I have no flat scraping expertise and no surface plate big enough to test it (the block is about 3'6" long).

Someone mentioned a rattle can, as it'll probably only be a few thou to build up I wonder whether there might be some mileage in that, with a zinc or zinc-Al 'cold galvanising' spray? Would that take the heat better than an epoxy compound?

Tim

Charles P
03-24-2011, 04:20 PM
No, it's blowing between cylinders, it's a fairly narrow land between them and of course a bit more of it gets eroded each time a gasket blows.

The new gasket is having to be specially made in solid copper, previously it's been old stock copper/as**stos but no more are to be found (it's a 1954 engine). That might give it more of a chance than the composite gasket.

No, as I've already said, taking the engine out and stripping it to do the job properly is NOT an option at this stage.

Thanks

Tim


The nice Mr Johnson of Johnsons Gaskets in Bradford can make you a head gasket with an extra fillet between the bores to help with this problem. My Fiat (sidevalve 1500cc) ran on one of those to cure a blow between 2 and 3 cylnders until this year (for 14 years). The engine is now coming out for a proper repair.
In my experience solid copper head gaskets are very intolerant of imperfections.

Charles

vpt
03-24-2011, 05:01 PM
This all seems very familiar like we've discussed this very same topic not long ago.

v860rich
03-24-2011, 11:26 PM
It's a bit out of the ordinary, but could you build up the area using a metal spraying technique? It might give enough build that a gasket is properly supported.

Michael

We've used the metal spray technique on one of my race engines. Blown head gasket between 5 & 7 on a SBC, cut about .125 out of block. The guy that did my machining at the time said bring it over with the head removed and we'll fix it in the car.
He had a torch with the spray setup and built the burnt area up, filed the top of the block flat and used a die grinder to finish the cyl. bores.
Ran the last 5 nights of that season without a hitch.
This was a circle track race car with 13.5 to 1 comp. ratio, on gas.

THANX RICH

People say I'm getting crankier as I get older. That's not it. I just find I enjoy annoying people a lot more now. Especially younger people!!!

J Tiers
03-25-2011, 12:12 AM
In my experience solid copper head gaskets are very intolerant of imperfections.

Charles

This sounds very familiar.... seems like I have been there myself.......and makes sense if you think about it, since which is going to "flow" better...... copper, no matter how soft, or "asbestos pudding", if both are in gasket form?

No way the copper is going to "flow" into a hole.... not with the pressures you can get with the studs/nuts.

weld-up file flat seems possible, maybe.... something has to fill that void. If it is gasket "body", and it it flows or expands (fails to squash as much) from "elsewhere", then the "elsewhere" is going to be a bit thin instead. or not packed as tight in the case of fibrous stuff.

Even if you filled it with copper shim filed/pounded flat on top.... locked in by the roughness of the surface...... at least there would be more material.

Which last goofy idea suggests possible brazing and filing... easier to file, less aggressive on the block than NI-rod, likely to lock in OK, especially if given some "help" by a groove or so.

vpt
03-25-2011, 09:17 AM
Can you get a pic of the area? I think it would help if we had a visual of how much room there is between the cylinders to work with and how deep the imperfection is.

firbikrhd1
03-25-2011, 10:30 AM
68 - '70's era small block 340 Plymouth/Dodge engines had difficulty with blowing head gaskets between cylinders. The were high performance engines from the factory with 10.5:1 compression and only four bolts surrounding each cylinder, 10 bolts total per head. High performance modifications only made the problem worse. Good engines other than that weak point. The solution: "O" ring the heads with .031" piano wire around each combustion chamber and install with new gaskets. Problem solved.

hardtail
03-25-2011, 12:21 PM
I take it this is a sleeveless engine?

saltmine
03-25-2011, 12:24 PM
Been there, done that....many times. Usually, it's common sense that's going to tell you which repair is going to work, and which one isn't.
If you want to spend days dancing around it with a bunch of feathers tied to your waist and a dead chicken to swing, be my guest.

Pulling the engine to resurface the block seems impractical. Welding, to me, would be the most practical. Most everybody forgot, this is a diesel, and even though it don't turn very fast, there are some very high pressures and temperatures to deal with. JB Weld isn't going to "cut it".

My two cents; weld or stitch-pin the low area of the block, and grind it down to the correct height. Stainless steel fire rings would be my choice fo the combustion chambers. The heat & pressure in each cylinder would make copper a poor choice for a head gasket. We tried that once on a race motor. The copper liquified and sprayed out like water.

Steve Seven mentioned the infamious Vega. I've done more Vega repairs than I care to remember. Since the cylinders are free standing, and the top of the block was open, overheating would cause the center cylinders to "sink". During one of many repair jobs, we used an air powered, 24" panel sander, with 240 sandpaper, and a straight-edge to cut the block down to the lowest cylinder. The repair went well, never failed again, and the car ran like a raped ape, because of the extra compression.
on another "sunk" cylinder job, I discovered that Chevy Corvair head gaskets were the same size as the tops of the Vega bores. A careful measurement and the proper number of Corvair gaskets had this one back on the road in no time. (yes, I used a Vega head gasket on top of the corvair gaskets...)

"O" ring the block & head? No. Even though it's a good idea, proper "O" ring installation requires machining both the block & the head to properly retain the "O" ring.

firbikrhd1
03-25-2011, 10:58 PM
"O" ring the block & head? No. Even though it's a good idea, proper "O" ring installation requires machining both the block & the head to properly retain the "O" ring.

I'm going to respectfully disagree with your statement. The "O" ring setups I am referring to are used with a head gasket. By adding "O" rings to the heads a high pressure area is produced around each cylinder right where problem exists. This was common practice on many high compression engines or engines with blowers during the era of muscle cars, and did a good job. There were articles in the enthusiast magazines (Hot Rod, Popular Hot Rodding, Car Craft etc.) back then, recommending the procedure exactly as I have described it. The "O" rings protrude only half their diameter, in this case a little over .015". It would be difficult to cut grooves for "O" rings in both the block deck and heads that matched perfectly and if no head gasket was used they "O" rings or seals of some type also be required around each oil and water passage as well. I don't know what would happen if "O" rings were used on both surfaces with a head gasket. It may cause more leakage if the weren't aligned exactly and cause shearing of the gasket or worse, stress points that lead to a warped or cracked head.

wierdscience
03-26-2011, 09:18 AM
Silver solder and a file is one method that works and metalizing is another.Both can be done in place and both will exceed the strength of the base metal.

Cheeseking
03-26-2011, 11:47 AM
Okay, this must be add metal day. I just posted this link as a possible fix for the guy with the scored propeller shafts. It is a portable process but you would need to find a local outfit to do it. No relation to this site it was still in my clipboard from the last post! http://www.o-e-m.net/journal.htm (I used to perform this process at my last job and we could do flat areas as well. Shafts are easier because you need to maintain relative motion and can turn in a lathe usually )

John Stevenson
03-26-2011, 02:17 PM
Given the size of this engine and the fact Tim has to get it flat after whatever process is used has to be taken into account.

Brazing or welding bring their own problems to the table in terms of heat input needed and the cleaning up of after. Given that a whole industry has arisen for on site machining with boring machines and such machines as the Versamill here's my take on it.

Get one of those cheap mini mills, remove the column from the base and bolt onto the bed so the spindle overhangs the side of the bed.
Then bolt the machine to the block face so the table travel is between the cylinders and carefully [ is there any other way :rolleyes: ? ] mill a long keyway.
This keyway needs to extend into the unworn section of the block and be wide enough to provide a seal for the gasket.

Getting a key to fit is then reasonably easy as it's only a small part and can be ground, milled or even filed to suit. You only need a straight edge long enough to do the width of the block.
Basically the key replaces the worn part of the block, it can be pegged into position but it won't go anywhere because it's a closed slot and the head is holding it down as a pressure fit.

The cost of the mini mill won't be wasted as in this setup it can be used to preform similar operations and work as an adjustable small mag drill without the magnet :D

Very handy for drilling out broken studs etc very accurately.

vpt
03-26-2011, 08:08 PM
Excellent suggestion! Along that same lines if the blemish is small enough even just drilling a hole and putting in a round peg might be enough.

Timleech
03-27-2011, 10:06 AM
Given the size of this engine and the fact Tim has to get it flat after whatever process is used has to be taken into account.

Brazing or welding bring their own problems to the table in terms of heat input needed and the cleaning up of after. Given that a whole industry has arisen for on site machining with boring machines and such machines as the Versamill here's my take on it.

Get one of those cheap mini mills, remove the column from the base and bolt onto the bed so the spindle overhangs the side of the bed.
Then bolt the machine to the block face so the table travel is between the cylinders and carefully [ is there any other way :rolleyes: ? ] mill a long keyway.
This keyway needs to extend into the unworn section of the block and be wide enough to provide a seal for the gasket.

Getting a key to fit is then reasonably easy as it's only a small part and can be ground, milled or even filed to suit. You only need a straight edge long enough to do the width of the block.
Basically the key replaces the worn part of the block, it can be pegged into position but it won't go anywhere because it's a closed slot and the head is holding it down as a pressure fit.



I'm a bit confused how you propose to get the cutter travel? Somehow secure the XY table itself to the engine block?
Going down that route, there's always one of these:-

http://i559.photobucket.com/albums/ss38/Timleech_2009/Keychisel-1.jpg

Capital outlay is lower ;)

The owner is doing the donkey work with this job, I'll try to get a picture and some measurement when he's got the head studs out and the sh*t scraped off the block.

Thanks guys for suggestions

Tim

aboard_epsilon
03-27-2011, 10:14 AM
ive seen someone butter each side of the head gasket with hylomar ..when they had problems ..and the thing lasted for years after .

all the best.markj

john b
03-27-2011, 07:23 PM
There are are two possible solution that i can see. Rent a portable mill from Climax, or purchase some Copaltite. If you cannot find Copaltite there is a company called Deacon Industries that has similar products. john b

A.K. Boomer
03-27-2011, 09:03 PM
I once welded up a burnt spot in an auto V-8 block between cylinders in the car. I used a buzz box and Ni Rod, then filed it flat. The repair was working years later when the guy sold the car.

If You try welding it and it doesn't work, You are only out a few bucks for the rod and a little time...it isn't any good the way it is now.
The lock pin method mentioned earlier might be a decent option to look into.

One other not very practical option would be to hand scrape the block flat, but I would only use that as a last resort.

Steve


Iv read everyone's reply's and im giving it up for doctor demo, I don't think I would mess around with trying to jam in a keyway - diesels have a funny way of telling you stuff wont work, it usually ends up in total disintegration...

lead would fail almost immediately - epoxy would be a close second - silver solder and brazing could work but I don't like the amount of heat involved esp. around a cylinder bore close to TDC with an engine that has a 22:1 comp. ratio that is engineered to operate at or in detonation conditions...
for small surfaces Buzz boxes get it over with, and you can stuff the bores with wet rags if you want...

Years ago I had a BMW 1600-2 that ate an upper compression ring and it dug a major pit right at TDC, I could not afford a re-bore and brand new kolbenschmidt pistons, I had no idea what to do except for welding it - the thing is-is I knew nothing about welding cast - I thought you just did it and that's it - so someone tells me of this old farmer in town and I take my block to him and tell him what I want and he says "you want me to do what?"
I tell him again and he spits some chaw on the ground right bye my shoe and says "Weeehl maybe I gotta idea" --- "I thin I can do it with some nickle rod"

I tell him to go for it - pick up the block and pay the man, notice that there's a few burnt little "spatters" close to the weld that pitted the block some and say to myself "so what - Porsche builds cylinder bores with spirals or drilled divots inside just for the oil retention and they charge big denaro's for it"

So I get the block home - I file the nickle weld down and then hone it in to fit the bore for the new rings and the original pistons modified for ring spacers - a tool that refinishes the ring lands allowed me this option and its better that stock due to the spring steel spacers being installed on the "load side" of the comp. rings land,
anyhow --- reassemble and break- in then run a leakdown test with piston placed at TDC --- not perfect but acceptable ---- 5 years later after severe beatings in every way imaginable and shifting out @ over 1,000 rpm's past redline for most of the engines service, run another leakdown and it was 2% better,

Im not always my own hero --- that farmer will always hold a very high place for me -- people who take an educated guess and that guess pans out are golden --- it means their educated guess actually had some education behind it:)

surely if I can match up some nickle weld in a cylinder bore to seal off combustion pressures you can do it on a flat cylinder head surface and there is no way in hell even a diesel will spit that out....

just my two cents.

hardtail
03-27-2011, 09:58 PM
1954 the comp ratio is probably around 17:1.....just want to know if it has liners wet/dry, flush, proud, shy?

wtrueman
03-28-2011, 12:13 AM
OK: Here's my problem: I have 4.0 L. Ford V-6. A head has cracked. High mileage. Can I do something about that or what to do? The Explorer is cherry and I kinda want some some idea about a "newer", less km, motor or what? BTW, are all the Ford 4.0 compatible if I find a better motor but it is standard rather than my auto? Thanks for your time, Wayne.

hardtail
03-28-2011, 02:43 AM
Depending on where the crack is replacement head or lock n stitch pins would be a good canidate repair here.......if you want to repair vs replace.

Timleech
03-28-2011, 03:02 AM
1954 the comp ratio is probably around 17:1.....just want to know if it has liners wet/dry, flush, proud, shy?

Dry liners, flush AFAIR


Tim