Head Gasket, aviation gasket eliminator?

[justinray]

I'm getting ready to start buying a block, and rebuild it, and am looking at the overall plan I want to follow through with. I'm considering using aviation gasket eliminator instead of the gasket, I believe if I have the block and heads decked flat it will seal better than a gasket, have no weak point since it would mostly be metal to metal, and be cheaper. I would have to find out how thick the stock gaskets are when crushed, and deck the pistons that much since the valves would be closer, and find lifters that were that much shorter but all in all, I think it would be more boost friendly. Thoughts?

 

[79jasper]

I REALLY don't think that'll work.
But following to see what everyone else says.

 

[IDIBRONCO]

Never heard of it

 

[riotwarrior]

USE HEAD GASKETS...your plan is not one that would work well in a daily driver IMHO...

Plain and simple use the gaskets!

You would need custom pushrods too....not LIFTERS...

And a custom INTAKE too....

 

[racer30]

Ya what he said^^^^ Running no gasket will put the head .085 closer to the block, The pistons are above deck .030 or more, Intake wont fit, valves will hit the pistons. lots of nasty things will happen. You woud need to cut the pistons .120 just to get back to 21.5 to 1 Cheeper? no way.

 

[idiabuse]

hmmm, bitting my tounge here!

That theory does work very well on exhaust manifolds, I do it all the time.


Javier

 

[Wicked97]

No that won't work.....ever.

Decked flat or not heads and blocks twist expand and move at different rates and there is no sealant in the world that will work.

Honestly I doubt it would run for a second before hemorrhaging coolant, oil and combustion gasses everywhere.

 

[idiabuse]

X2, what he said.

 

[79jasper]

Just for S's&G's as an experiment if you don't believe them, try it on a lawnmower engine or something. Run the hell out of it too.

I don't know if it'd have high enough compression and cylinder temps to be a good example though.....

 

[justinray]

Well dang, it was just a question and a tired question, I want to build the engine that stays in my truck for the rest of it's career, looking into a lot of different things, so far that's thr one I really didn't know about.

 

[lotzagoodstuff]

Do a search on hylomar sealant, several folks have used is with stock headgaskets to improve sealing, but as you can tell the general consensus is that bolting heads to an IDI without gaskets is a bad idea. Do a search, lots of head gasket info/experience/feedback on here, but if you really want the heads to stay on for the longest time, you need to consider studs, which have an associated cost.

Good luck

 

[icanfixall]

Good question to ask here before you tried this.. As posted.. Its just not practical to try this. Our heads are flat and so is the block. Now the pistons raise up out of the block as much as 31 thousands. If there is no gasket then the pistons will need at least 31 thou cut off the tops. Now the heads are goning to be around 70 thousands closer to the block because you wont have the gasket acting as a spacer between the two. So what happens with vale to piston contact is anyones guess. As it is the piston to valve missing contact is very little as it is. So I'm thinking there would be horrible contact before the engine actually ran.
why are you feeling you want to attempt running without a head gasket. We have very good luck with the felpro and victor reinz head gaskets. Also using some hylomar spray on both sides of the gasket will keep a seal beyond the gasket. This has been proven a few times too. Adding an ARP head stud set to this will take away any head gasket failure issues. My stock 1989 7.3 ran it complete life with a oem head gasket on it. I installed a Banks turbo and boosted to 13 lbs hauling heavy all across this country. The passenger side oem head gasket had over 370,000 miles on it with the oem head bolts. Maybe I got an engine that was made on a good day.. Maybe not.. I just know I worked it hard and no failure. What makes you feel the head gaskets are going to fail. I know the 6.9 head gaskets had some issues but that all finished now with the better gasket gaterials available...

 

[lilredtdi]

I would never trust sealant here. Not sure about our trucks but most diesels have piston protrusion. The reason compression is so high in a diesel is in most cases the piston and valve share the same space which is why proper timing is critical so valves and rods do not end up pretzled.

To my knowledge the head gasket thickness in a diesel is critical to maintaining the proper spacing between the piston and valves.

Now that being said, for additional insurance to the head not leaking you could spring for ARP head studs. Even if you plan on running a stock setup it will just be extra insurance.

 

[justinray]

In all honesty, I asked because I am being taught int the industry, mated metal seals better than any gasket, and leaves no weak points. I'm not trying to reinvent the wheel or anything, just seeing why this does not apply in the diesel world, and figured this would be the best place to ask. Especially before attempting it.

 

[dansvan]

most of the air cooled Volkswagen engines do not use head gaskets. I've built an air cooled Porsche engine with no head gaskets. However they are not diesel compression ratios and do not have oil or coolant to deal with.