VCCA Home Forums TECHNICAL - 1945 AND EARLIER 1929-1932 '32 Engine enamal burning off exhaust ports

I guess I have graduated to a whole new class of questions - "Why does my '32 Chevy do this (insert description) when it runs?"

I've done a BB search and come up empty handed. After less than 1500 miles clocked on this restoration, the BH engine enamal has burned off of exhaust ports cylinders 2&3 and 4&5 on the engine head on both sides of the carburetor.




I have recently noticed the same bald patches on other '32 engine heads at exhaust port 2&3 and 3&4 while on tour.

Is this just a normal circumstance of dumping hot exhaust gases from two cylinders into one port?

If you use normal enamel paint it will not tolerate the heat at the exhaust ports unless you have used a good primer. Even if using a good primer it may not last but has a better chance. If you use high temperature engine paint it will not burn off in that area.

BH engine enamel was used to paint the engine. However, the preparation and the primer before final coat are suspect and are likely substandard.

As you know the old BH paint is incorrect and, as Chipper stated, it will burn off in those areas because it is not high temp. paint. Any paint that is not high temp. will most likely burn off in those areas as well. One solution is to have the cylinder head powder coated with a high temp. coating.

I would bet that you would find this with all the engine paints sold today as they are not high temperature paints as you would apply to an exhaust manifold. Would bet that the same thing happened when they were new just as the paint burnt off the exhaust manifold before the car left the dealer.
A more modern example is the in take manifolds on the V-8 engines, The paint will burn off on either side of the carburetor where the exhaust passage is. The original was also burnt of on my '39 when I bought it but is was 35 years old at that time.