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Fri Feb 13, 2009 6:55 pm

I tore down my 1300 to do a rebuild. An earlier rebuild had added the 85.5mm. I am going to go with the 87mm kit on the my rebuild. My question is" the motor I tore down had head gaskets. The overhaul gasket kit I purchased has no head gaskets. I was told the heads would seal ok without them. Will the heads leak with out gaskets? and doesn't it change the compression ratio.
Good info is all Im after. Will it or will it not ????????

Fri Feb 13, 2009 7:58 pm

I thought it was strange that my 1200 did NOT have head gaskets when I tore it down. It sealed just fine. The engine ran great with NO head gaskets, just spun a bearing :cry:

Fri Feb 13, 2009 8:16 pm

raccoon wrote: I tore down my 1300 to do a rebuild. An earlier rebuild had added the 85.5mm. I am going to go with the 87mm kit on the my rebuild. My question is" the motor I tore down had head gaskets. The overhaul gasket kit I purchased has no head gaskets. I was told the heads would seal ok without them. Will the heads leak with out gaskets? and doesn't it change the compression ratio.
Good info is all I after. Will it or will it not ????????

Describe "head gaskets"... you had small thin copper rings out the outside of the cylinder tops that were crushed there or did you have some "rings" inside the head/chamber where the cylinder surface mated to the cylinder head surface???

Fri Feb 13, 2009 9:19 pm

Compression Ratio spacers??
The copper rings were actually discontinued on the fresh air engines.

Fri Feb 13, 2009 9:26 pm

Russ Wolfe wrote: Compression Ratio spacers??
The copper rings were actually discontinued on the fresh air engines.

That's what I was getting at Russ... *Some builders put rings(not copper but some cheap ass stamped steel shit) inside the cyl head to jug ( I am talking about GEX and others and not PRO racers who use copper shims there etc etc) which is not ** IMHO and experience a good idea.

Shims if needed to adjust for cutting the deck and flycutting the head surface should be calculated and added to the BASE of the cylinders not just stuck in the head between it and the cylinder.

And you are of course right there would be no need for the other thin copper "crush washer" that fits a different part of the cylinder to the head seal on any later 40 hp or later 1300, 1500 ,1600 "fresh air" engine.

IF he has heads with the "spacers" as I am thinking he needs to get rid of them

Fri Feb 13, 2009 10:57 pm

I have seen heads that had been cut so deep, that the cylinder hit the cooling fin portion not the combustion chamber. I have a couple heads here right now that have had the fin area machined away so the cylinders would seal.

Sat Feb 14, 2009 7:30 am

Russ Wolfe wrote: I have seen heads that had been cut so deep, that the cylinder hit the cooling fin portion not the combustion chamber. I have a couple heads here right now that have had the fin area machined away so the cylinders would seal.

And that is the kind I am talking about... fly cut so deep that some builders like GEX would put a spacer in the head and use them. Which usually ended up badly with a head that wouldn't seal later down the road. :roll:

Sat Feb 14, 2009 9:26 am

The head gaskets or rings that I removed from the heads are metal rings that check .062 thick. I placed the jug in the head without the ring and it has clearance between the head and jug fins. Since the rings have no effect on the deck height they must have been installed because of excessive machining inside the head seat area. I know these rings have an effect on the valve clearance and compression ratio. Should I use the rings on the rebuild or purchase a new set of heads?

Sat Feb 14, 2009 9:34 am

raccoon wrote: The head gaskets or rings that I removed from the heads are metal rings that check .062 thick. I placed the jug in the head without the ring and it has clearance between the head and jug fins. Since the rings have no effect on deck height, would I have a problem with valve clearance. Since the heads are reconditioned, I would thank it has to have something to do with the compression ratio or valve clearance.

I would remove those rings and instead use .060" shims under the cylinders and lap the cylinders in the heads with valve grinding compound to make sure you do have a proper seat all the way around the combustion chamber / cyl to head mating surface.

Sat Feb 14, 2009 9:51 am

Do I need to put gaskets on both sides of the rings or could I just use use a good silicon sealer? What could possible happen if I assembled with no rings at all?

Sat Feb 14, 2009 10:04 am

raccoon wrote: Do I need to put gaskets on both sides of the rings or could I just use use a good silicon sealer? What could possible happen if I assembled with no rings at all?

Read this on sealing the bottom of the cyls to the case

http://www.thesamba.com/vw/forum/viewtopic.php?t=340710

Unless you can set up and measure your deck height, and "cc" your combustion chambers and plug the numbers into the formula for figuring your compression ratio your not really going to know.

I was just saying I prefer to build with a shim under the cylinder to make up for material machined off the case deck or flycut off the heads than to use those "head spacer shims"

Sat Feb 14, 2009 10:24 am

I agree, Now who supplies these shims that I need?
Thanks for the good information.

Sat Feb 14, 2009 10:37 am

I have seen many of those aluminum head spacers burned out. They will not burn out if they are on the bottom of the cylinder.