head gasket repair sealant-does it work?

jrisingmoon · Aug 7, 2006

I was looking through an auto retail store and saw that there is a head gasket repair sealant similar to a radiator sealant. I'm pretty sure I've got either blown head gaskets, or valve cover gaskets, if not both, and can't get around to replacing them for who knows how long. Has anyone tried this stuff as a cheap alternative to new gaskets? I'm probably going to give a shot at some point since it seems easy enough.

icanfixall · Aug 7, 2006

Its probably a waste of time and money because these motors make about 500 lbs of compression. But if you try it you may see that it works. I really dought that it will help anything. Remember this. You have .030 clearance between the head and the piston. Fluids will not compress so that piston either leaves the cylinder or the rod makes a window in the block. >030 is 10 sheets of notebook paper....

krawlr · Aug 7, 2006

jrisingmoon said:
I was looking through an auto retail store and saw that there is a head gasket repair sealant similar to a radiator sealant. I'm pretty sure I've got either blown head gaskets, or valve cover gaskets, if not both, and can't get around to replacing them for who knows how long. Has anyone tried this stuff as a cheap alternative to new gaskets? I'm probably going to give a shot at some point since it seems easy enough.

Blown head gasket would cause running/cooling issues. If it's just oil leaking it's more likely a valve cover gasket. Unless you're having nasty blowby issues I'd just put valve cover gaskets on it. When chasing oil leaks start with the suspect closest to the top.

Diesel JD · Aug 7, 2006

Hey, if you are having oil leaks, it might very well not be the head gaskets at all. The valve covers, valley pan, CDR, and gear cover are all likely places. The head gasket issues usually comes from external leaks on the coolant side. I would pressure check the cooling system to see what the verdict is.

jrisingmoon · Aug 7, 2006

icanfixall said:
Its probably a waste of time and money because these motors make about 500 lbs of compression. But if you try it you may see that it works. I really dought that it will help anything. Remember this. You have .030 clearance between the head and the piston. Fluids will not compress so that piston either leaves the cylinder or the rod makes a window in the block. >030 is 10 sheets of notebook paper....

So basically your saying that the head gasket sealant will probably just shoot out the sides and not seal anything?

Mr_Roboto · Aug 7, 2006

I assume you are talking about ceramic block sealer, not standard "stop leak". I also assume you are talking about coolant leaking somewhere.

Years ago, I severely overheated a 351w and cracked the heads or blew the gaskets. I wasn't going to take it apart to find out which. It billowed white smoke like crazy from coolant burning.

I carefully followed the instructions for the ceramic block sealer, no more coolant loss for the several months I drove it after. The truck was a piece of (@#$ and I sold it, but I would have expected the "patch" to last a while.

I say that if the problem is something that the block sealer is made to patch, go for it. If it doesn't work you are out the money for the sealer. If it does work, even for a few months then you are ahead that much.

Black dawg · Aug 7, 2006

ive also seen the ceramic type work and sometimes way longer than seems possible. never tried it on a diesel, but thinking of trying it on my 6.5td burb

IDIeselman · Aug 7, 2006

I believe you are after 2 cans of KW block and cylinder head sealant, comes in a blue can with silver lettering IIRC.My father has been running this patch in one of his medium duty wreckers with a 6.9 for 2 years now without a problem.Just be sure to follow the directions to the letter.

Diesel JD · Aug 7, 2006

There was a guy over on the Diesel Stop that said he used teh Bars pellet type sealer. Said it saved him from having to do head gaskets on his 7.3. I used some of teh Bars in a Bottle for my Dad's Isuzu P'up with the gas motor which seemed to have more of an internal as well as external leak. Seems to still be holding, though I'd have to get an oil sample to be real sure. No more coolant loss at all though that I can see. I haven't tried it ona diesel but there are those that say it works. The caution is some others say the stuff can plug up things you really don't want plugged, but that's really something I'm surprises we ahven't heard from Scott about.

jrisingmoon · Aug 8, 2006

Yeah, I'm kinda afraid that something unwanted will get clogged, too, but if that happens, I'll just pull the engine like I had planned anyway, fixin it all proper like.

Mr_Roboto · Aug 8, 2006

Bar's is a far cry from block sealer. They are completely different products that work in different ways.

Block sealer hardens only once the water is drained and it's exposed to air. I would not expect it to "plug" any passageways etc.

jrisingmoon · Aug 8, 2006

There isn't any coolant leaking that I can see, but I do see substantial oil leaking where the heads meet the block on the left and right bank. Lots of black smoke, too. The timing could be off but I don't think an off-timed engine would cause THAT much black smoke. I put in an RDT to bypass the CDR, and I was able to get into 3rd gear as a result.

I saw Bar's in the store, as well as KW. What's the different between Bar's and KW? ceramic block sealer and stop leak?

Mr_Roboto · Aug 8, 2006

If you are trying to fix an OIL leak, coolant stop leak will not help.

Bars is sticky, and sets up in holes as it hits the air outside of the leak. Block sealer coats everything with a thin layer, and that layer hardens when the water is drained.

jrisingmoon · Aug 8, 2006

This is the Bar's stuff I was talking about just to be sure we're on the same page:
Bar's Leak

I know that Bar's makes radiator stop leak. I didn't know if it was any different than that stuff though.

offroadohio · Aug 8, 2006

as said above an oil leak cant be repaired with coolant leak fixers uppers.

head gasket repair sealant-does it work?

jrisingmoon

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