Topic: V8 Exhaust manifold blue overspray?

[Morsel]

Not sure this should go here, but I was just curious about the exhaust manifold blue overspray ghosting on the top and how that came to be or why it was done? I mean what was it done for or when in the process, it’s seems interesting to me that it exists since the engine was sprayed without them on first or else if not, wouldn’t there be more blue on them and have unpainted areas on the block  underneath as well.

I was looking through the unrestored threads and saw some shots and it got my curiosity going about that.

Thanks,

Jason

[Bob Gaines]

Not sure this should go here, but I was just curious about the exhaust manifold blue overspray ghosting on the top and how that came to be or why it was done? I mean what was it done for or when in the process, it’s seems interesting to me that it exists since the engine was sprayed without them on first or else if not, wouldn’t there be more blue on them and have unpainted areas on the block  underneath as well.

I was looking through the unrestored threads and saw some shots and it got my curiosity going about that.

Thanks,

Jason

As far as we know the SB exhaust manifolds were on the engines when they were painted. The evidence on survivor cars supports that.The overspray on the exhaust manifolds happened as a matter of the procedure of painting the heads. The exhaust manifolds were not intended to be painted and so only got a little overspray from the head painting process. Yes ,many times the engine block behind the exhaust manifolds didn't get much paint . It depended on which type of exhaust manifolds . Some exhaust manifolds covered more area then others.The same procedures were in place for a number of years apparently. There are 1970 vintage copies of the Ford Engine painting directions used for a 1970 Boss which indicates minimal amount that is acceptable on the exhaust manifolds. This first of all confirms the evidence on survivor engines that we have seen in which the exhaust manifolds were installed when the engine was painted and second why the amount of overspray was typically small . There is no reason to think that the 1970 document describing the engine painting procedure is much different then the 1965 procedure given the survivor evidence.

[Morsel]

Thanks for the info Bob, as I mentioned I was just noticing in the unrestored photo section that it seemed like they were so lightly over sprayed and it looked like really good coverage all around the exhaust manifolds  that I wondered how they got good coverage on the block, but such a light spray on the manifolds, seemed like maybe it was two applications, but we know they never took time to do things twice

Thanks,

Jason

[67gtasanjose]

Thanks for the info Bob, as I mentioned I was just noticing in the unrestored photo section that it seemed like they were so lightly over sprayed and it looked like really good coverage all around the exhaust manifolds  that I wondered how they got good coverage on the block, but such a light spray on the manifolds, seemed like maybe it was two applications, but we know they never took time to do things twice

Thanks,

Jason

Paint burns off the manifold where they get the hottest, not so quickly right up against the heads. Higher mileage cars often it hard to see any remains of the blue left at all.

[J_Speegle]

............. I was just noticing in the unrestored photo section that it seemed like they were so lightly over sprayed and it looked like really good coverage all around the exhaust manifolds  that I wondered how they got good coverage on the block, but such a light spray on the manifolds, seemed like maybe it was two applications, but we know they never took time to do things twice

Not unusual for there to be either very thin or no coverage directly behind the lower edge of the exhaust ports especially towards the center. I've applied a base cast color to the area on some engines just to protect the metal if the blue doesn't reach up in all the corners because of this. Think they likely covered much more with the blue and it just baked off that would we would think would "look right"



As mentioned in another thread if you look at the original black and white pictures we have here on the site you can make out the glossier paint that was applied to, especially, the top sections of the manifold. Much of it baked off over the next few months, then rust and the elements continued to reduce the remaining paint over the years.

Looking at some of the pictures I noticed just some of the following

- 64 Engine test picture seems to suggests only the top of the runners (only the first is visible in the picture) got some paint

- 68 San Jose engine drop. None of the exhaust manifold bolt finish stand out against the color of the block and exhaust manifolds along the top edge

- Hard to tell if the manifold and all the mounting hardware is not completely painted in the picture thread showing the 17,000,000th engine . Picture does not appear to be a display or "show" engine since things like the harmonic balancer is not completely painted (bare center and scrapes) Painting masks still in place

- Just one of the collection. This manifold looks like it may have allot of paint towards the front and top edge while it fades away the further rearward and downward you go

[CharlesTurner]

With the manifolds in place, to get decent coverage of paint in the spark plug area through the manifold openings will leave a bit more than a ghosting of paint.  The original paint was sprayed relatively thin, which is one of the reasons it's rarely seen on original cars.  Although, anything more than a few thousand miles would most likely have burnt off most of the paint anyway.

[J_Speegle]

Though not regular production (pilot plant car) the engines were likely built and painted at Cleveland. Because they painted them a very light color it provides is a possible glance into where paint on regular production V8 engines for 65-66 was applied and how. Yes someone dropped an extra bolt in one of the intake valleys.  There were just starting to work some of the bugs out of production - the purpose of pilot plant builds   Maybe someone pulled the aluminum engine ID tag for some reason




NOTE: Remember don't copy the details seen in the picture above

[Morsel]

Thanks all for all this interesting information and process on how this was done. I find it all fascinating...