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Discussion Starter #1
What is your experiences using copper head gaskets?

I have one to install on a 7.6 & will anneal it before installation. Will torque to specs.

Good or bad, like to hear what has happened….

Thanks.
 

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Where did you get the copper gasket?
Thickness?
Approximate price?

Have only seen the metal/fiber composite type and the fiber/mesh type.

Thanks

Sorry, didn't blowup photo to see you numbers!!
 

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Discussion Starter #3
Where did you get the copper gasket?

Approximate price?

Have only seen the metal/fiber composite type and the fiber/mesh type.

I bought this off ebay a while back. The ebay seller still offers hundreds of copper gaskets but not L model. If this one works it may be worth contacting him.

Paid about $24.

I tried the aftermarket gaskets, but you have to replace them each time you remove the head.

Will post results......
 

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Gravely1964
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I have been curious about this for years. I just never have bought one to try. The new fiber ones are total crap in my eyes.

Please do post the results and keep us posted
 

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Daryl G
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I, too, am very interested in this! The last head gasket I purchased was purportedly out of a 'improved material' but I am less than impressed - it is way too stiff and I had some sealing issues from the get-go. I looked for some sheet copper earlier in hopes of fabricating my own but it was cost prohibitive...
 

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Discussion Starter #7
Research used & found 2 major requirements, flatness and cleanliness is required above the normal rebuilding / tune-up requirements.

Of the (3) 7.6 heads I have, the one that was on the jug before rebuild is the best fit for flatness.

The other two heads rocked back & forth on the jug. The gap was about .008 around the center of the head (piston area). It was a surprise the warp & rocking was forward to rear direction on the jug.

Currently working to clean seating surface on head & jug. Objective is to have it as close as possible to new where you see the original mill marks.

I am at least a month out before the initial run. Need to order more parts……
 

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I have had 6.6 and a 7.6 heads resurfaced as a matter of course on the two engines I am currently working on: 0.010" off the 6.6 head and 0.065" or so off the 7.6 head. The cylinders/jugs tend not to be so critical I believe because of the mass of the part compared to the heads which with the 6.6 are really pretty thin. I am using a copper coat gasket spray on the composite gaskets since you have to replace them each time anyway and if I can get a copper gasket, most surely would use a sealer of some type with them. If you have to do a valve job I would also recommend a light surfacing on the jug too, just to clean things up and give the valve cutter a new surface to start from.
 

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Discussion Starter #9
Quick update....


Gasket installed, see pic. Details on installation will be later.

Rebuilding the dead carb, should be ready to run soon.

This tractor was a non runner sitting outside farmers barn.
 

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Copper has a pretty low melting point.... Certainly well below combustion chamber temps.... It will be interesting to see how the copper gasket holds up.
 

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Considering that nitro burning drag race engines use copper head gaskets, I don't think this will be a problem with the little low compression T head engine.
 

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Copper has a pretty low melting point.... Certainly well below combustion chamber temps.... It will be interesting to see how the copper gasket holds up.
The cylinder and head are really good heat sinks. They'll keep the copper well below its melting point.

My air-cooled airplane engine produces exhaust temperatures approaching 1500F, but the head temps rarely get close to 400.
 

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Discussion Starter #13
Fired up & ran today on the second pull. Runs like a new 7.6.
Ran for about 15 minutes and after cooling down I retorqued the head bolts. Only two turned, they were just outside of the center bolts.

I have to repair the swifty pivot pin in the axle assembly. Axles did not want to turn. Pivot pin is bent, recall this tractor was a non runner ready for parts…..

This is what I did to prep for the copper gasket:

Clean gasket seating surface on jug. You will see the mill markings when clean.
Check flatness of head and cylinder deck, I had to have the head ground
Clean bolt threads in jug. Used starter & bottom taps.
Anneal the copper gasket and then clean gasket with steel wool.
Use brake cleaner on cooper gasket, head, and cylinder deck.
Clean items multiple times till you have a clean rag drying them.
Measured threaded hole in jug, was about ¾”.
Check thread protrusion after inserting bolt in head with gasket on the bench.
I found with stock bolts the protrusion was a 3/8”, I discarded them and installed 1 ½” bolts.
Torqued head bolts to 25 ftlbs IAW 1970 CSD.
Ran engine for about 15 minutes and let it cool
Retorqued head bolts at 25 ftlbs.
Will run & retorque 2 more times.
 

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Discussion Starter #15
They are back up on e-bay for sale right now.
I'd buy them again. Mine was purchased from "Copper Gaskets Unlimited" who sold them on ebay.

You should be able to reuse them, just have to anneal & clean.

Attached is a few pics.....
 

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Discussion Starter #16
I have 10 hours of use on this engine, past 3 hours I have run it without holding back. WOT & midrange mowing the yard with the CI-8 & kidney deck. Thick tall grass for up to one hour runtime. Copper gasket is holding and I anticipate no issues in the future. :tango_face_grin:

Will continue updating the post.....
RB in RI
 
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