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head gasket?

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Rebuilding a full race 1098 at the moment myself. Planning to use the Payen AF070 or TAM1212 head gasket with 22 gauge soft copper wire inserted under the fire ring and an additional piece placed in front of #1 exhaust end that looks like a "U", a single piece between 1/2, two pieces between 2/3, a single piece between 3/4 and finally another "U" behind #4. Been building 948's and 1098's this way for 25+ years. Also put a good coat of silver spray paint on the gasket before I lay on the copper wire pieces.

Use a modified putty knife to peel up the fire ring. A piece of 6" facia board to support the head gasket, a 4p finishing nail is on the board about 1/2" from the edge 2/3 of the way up the side to wrap the wire around to use for pulling around the fire ring, use finger nail clippers to cut the wire and a 4 oz. ball pein to gently tap the fire ring back down.

Same trick many of the good old A-Series engine builders used for years. Holds up to 16.0/1 in those full race 948's that used to run in HP for so long.

HTH,
Mike Miller
 
Question:

my payen head gasket was shipped with the cardboard packaging folded over to fit the shipping envelope. The tension created a slight bend in the gasket, eg. the metal cylinder surround. No kink just a slight bend. I suppose it will straighten out when torqued.

Any cause for concern?

Fred
 
As long as it did not crack the fire ring around the cylinder it should be just fine. If the fire ring is broken/cracked, return it. The cracked area will burn out from the cylinder conditions.

Mike
 
Mike: Sure would like to see a pic of how you place the copper wire. I've used it to cure problems on engines that should have been junked but never seen how it was used to hold a race engine together.

Kurt.
 
I'll be 'O' ringing a Payen AF070 head gasket tonight or tomorrow morning. Will take some photo's. Now I'm pretty handy around an engine, but this photo insertion thing has me stumped. If someone will help me figure out how to get a .jpg photo out of/off my computer and into this message, I'd be glad to share.

Got all sorts of pictures of stuff to share if I can learn how its done. I took some pictures of a piston with a shattered top ring where two segments overlapped each other and wedged into the groove. Good visualization of what I was warning about with worn top ring groove. Would help someone understand why ring groove clearances past 0.006" are not good at all. 6 is iffy, but doable. More than that guarantees ring breakage.

Thanks,
Mike
 
Now that TulsaFred helped me understand how to upload pictures, I'm going crazy!!!!

This one is of the tools used to 'O' ring the head gasket.

miykj9.jpg


This one is of the 'O' ring peeled up with the putty knife tool.

w8p8wx.jpg


Enjoy,
Mike Miller
 
Waiting for more with baited breath, Mike.

Kurt.
 
Okay, Here is the picture of the 22 gauge soft copper wire being pulled/placed under the fire ring. I use the hammer to gently return the fire ring to its almost original position with the wire beneath.

2ikz6ol.jpg


This is the picture of the shattered ring pieces in the very wide groove. This happens when the ring land starts to fail. Fatigue due to heat, detonation and exceeding usable life occur.

52j5nn.jpg


Mike
 
Nice work Mike, thanks for sharing..
I was lucky to see this done in Memphis by Phil & Tony Chiles one year when I was helping them in the pits. We had the head off because Tony had forgotten to remove one of the rags stuffed in the SU throats during storage after a previous race. :wall: Said it had a strong miss during practice........ :lol: Sure does magic for the high compression 948's.

Steve
 
Neat, golly knows we love pics.
 
Are the ends of the wire overlapped then, Mike, or butted up?

BTW, Great pics!

Kurt.
 
Got to be butted but waiting to see what Mike says.
 
Yep, Butted up. That's why I use nail clippers for the job. Put some tension on the wire with the board/nail tool and then tap down to very close to the butt up point. Cut with the nail clippers and then use the putty knife to push both ends under the fire ring and tap down to secure. If one side or the other needs a little trimming to butt up just right, then clip with the nail clippers. You are done for that cylinder and move to the next one.

Mike
 
Mike, you know Cometic make a head gakset for the 948/1098 now, Dick May has the part#, so does Bartell, I think you gotta order and handful at a time to get them, but Bartell said they worked like a champ. As for the street car on streetable compression ratio, I couldn't possibly see why one would have to do the old 948 racer trick. If they just made a composite gasket for thiese, life would be alot different. You street guys know to coat your copper gaskets right?

With Freddy T. racing his 1098 again, you guys should look at getting some of those MLS gaskets. Havilick, still doing 1098 rigth, I'm guessing Tony is 1275ing now.
 
Yes, Knew that Cometic had finally tooled up/programmed the embosser to make the unique pattern for the small bore A-Series engine on their MLS head gasket lineup. We just have a box full of the AF070 composite headgaskets left. When those are gone, will likely transition over to the MLS for the 1098's that Mike H. is running and the few 948s that I still build. Yep Mr. D is now using the 1275 LPHP's.

It is good to know that Cometic has both small bore and the 1275 style of Multi-Layer-Steel headgaskets. Shudder to think of where the price is now, but nice to know.

Mike
 
I still stand by the permatex copper spray. That stuff works wonders. I had a Madza truck that had a groove between 3 and 4 cylinders that you cold fit a piece of welding wire in and I sprayed several coats on it and a new head gasket and put 40k miles on that motor and as far as I know its still going.
 
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