Ceramic paint on push rod tube and exhaust pipe

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AZScott
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Location: Tucson, Arizona

Ceramic paint on push rod tube and exhaust pipe

Post by AZScott »

Have a question that I would like to get some advise on. I am in the process of rebuilding a ’64 turbo engine. I have been reading various documentation on doing a major engine overhaul. In the Finch book he mentioned coating the part of the push rod tubes and exhaust with ceramic V.H.T. paint. The theory here is to reduce the heat that is transmitted through the tube to the 0-ring seals to help preserve them and potentially prevent future leaks. Sounds like good advice, and anything proactive to help avoid potential oil leaks I am all for.
Have others done this?

And if so,,, what coating have you used ? I have a can of VTH very high Temp flame proof ceramic manifold paint, but it really doesn’t say it’s an insulator. It does say it helps heat dispersion to maintain & protect paint finish, and I am not really worried about the finish. So I don’t think this is the stuff Finch referred to in his book. The coating I see out there that appears to be best is Lizard Skin 1301-1 Ceramic Insulation, in 1 gallon tubs, at $84 plus shipping. But not really crazy about buying a whole gallon of the stuff. Is the Lizard skin worth it? I was also toying with the idea of wrapping the ends of the tubes with motorcycle fabric header tape like I use on my dirt bikes. Would appreciate any thoughts others might have.
Thanks.
63 Monza Coupe (164-4 carb)
64 Spyder Convertable
62 MGA Roadster
74 Norton Commando
69 Triumph Bonneville
Jerry Whitt
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Joined: Thu Sep 26, 2013 2:42 pm

Re: Ceramic paint on push rod tube and exhaust pipe

Post by Jerry Whitt »

The newer viton o rings are pretty good. The paint idea probably is not needed.
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lostboy
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Joined: Mon Nov 09, 2015 2:59 pm

Re: Ceramic paint on push rod tube and exhaust pipe

Post by lostboy »

Wouldn't the ceramic paint insulate them keeping the heat inside? Idk how I feel about that.


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-Steve
1961 Corvair 700 Sedan (80hp 3spd Gasoline Heat)
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Latrgatr
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Re: Ceramic paint on push rod tube and exhaust pipe

Post by Latrgatr »

My Dad followed Fred Johnsons book and coated the pushrods tubes on his car back in '87. Not certain how much it helped but it is still not leaking 30 years later.


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66vairguy
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Joined: Tue Dec 21, 2010 3:44 pm

Re: Ceramic paint on push rod tube and exhaust pipe

Post by 66vairguy »

There are two schools or thought here. Coat the pushrod tubes to keep heat out, DON'T coat the pushrod tubes to let heat out.

The real issue is you DO NOT WANT HEAT radiating from the exhaust tube into the puhsrod tube, BUT you do want the pushrod tube to conduct heat from the oil that flows from the head to the block.

What to do!! The latest technique is to use high temperature reflective foil ONLY around the the part of the pushrod tube in close proximity to the exhaust tube. Don't coat the rest of the tube with anything that will keep heat in.

Now let's keep in mind that almost two million Corvair engines ran fine from the factory so this "fix" is basically for those who are going racing and engines are exposed to high demands.

As far as wrapping the exhaust tubes to keep heat in - you'll have to makes sure they are the tubes from the latter Air Injection Reaction (SMOG) engines. Wrapping the standard steel tubes will probably cause them to get so hot they will fail. In the old days the turbo guys would wrap an insulation wrap around the exhaust pipes form the manifold to the turbo to keep heat in (heat is energy and the more heat the better a turbo works) and the exhaust pipes would deteriorate rapidly and fail. You need a steel alloy that will tolerate the extra heat from wrapping the pipe(s) in insulation. The Corvair heads with A.I.R. had exhaust port tubes made from a steel alloy that tolerated the higher exhaust temperatures and MAYBE they would tolerate being wrapped.
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lostboy
Posts: 410
Joined: Mon Nov 09, 2015 2:59 pm

Re: Ceramic paint on push rod tube and exhaust pipe

Post by lostboy »

66vairguy wrote:There are two schools or thought here. Coat the pushrod tubes to keep heat out, DON'T coat the pushrod tubes to let heat out.

The real issue is you DO NOT WANT HEAT radiating from the exhaust tube into the puhsrod tube, BUT you do want the pushrod tube to conduct heat from the oil that flows from the head to the block.

What to do!! The latest technique is to use high temperature reflective foil ONLY around the the part of the pushrod tube in close proximity to the exhaust tube. Don't coat the rest of the tube with anything that will keep heat in.

Now let's keep in mind that almost two million Corvair engines ran fine from the factory so this "fix" is basically for those who are going racing and engines are exposed to high demands.

As far as wrapping the exhaust tubes to keep heat in - you'll have to makes sure they are the tubes from the latter Air Injection Reaction (SMOG) engines. Wrapping the standard steel tubes will probably cause them to get so hot they will fail. In the old days the turbo guys would wrap an insulation wrap around the exhaust pipes form the manifold to the turbo to keep heat in (heat is energy and the more heat the better a turbo works) and the exhaust pipes would deteriorate rapidly and fail. You need a steel alloy that will tolerate the extra heat from wrapping the pipe(s) in insulation. The Corvair heads with A.I.R. had exhaust port tubes made from a steel alloy that tolerated the higher exhaust temperatures and MAYBE they would tolerate being wrapped.

As I was reading that I remembered that cerakote comes in a heat dissipating formula and a separate heat insulating formula. If one were so inclined to spend some money, you could do this insides with the dissipating formula and the exteriors with the insulating one. A lot of time and money for probably minimal results though.


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-Steve
1961 Corvair 700 Sedan (80hp 3spd Gasoline Heat)
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