Exhaust Manifold Finish

[Kirk M.]

Ok, see if this makes sense. This past spring I put two properly dated heads on my car. In the process, I removed the exhaust manifolds. I cleaned them thoroughly with steel wool and then coated them in WD-40. Since then, I have kept rust off them by wiping them with a rag covered in WD-40. I assumed this would keep rust off while maintaining a proper natural finish. The WD-40 just burns off once the manifolds are hot.

So, when I got the car judged this fall, I took a two point deduct on the exhaust manifolds because of finish. I told the judge there was absolutely no finish on the manifolds as I had steel wooled them down to metal. He said there absolutely was and maintained the 2 point deduct.

Is it possible that someone coated the manifolds before I steel wooled them and that I didn't remove the finish? Just doesn't seem possible to me because after I did it, it looked like bare metal.

Just puzzled.

Kirk

[Richard T.]

Re: Exhaust Manifold Finish

No oil was used after casting. A light coat of rust would soon appear on the manifolds. There may also be some orange over spray present as this was typical when the engine was painted with manifolds and heads in place. The orange over spray would be present near the exhaust ports and the bell housing. The manifolds do look nice when bright but that is not the correct finish.

[Tim S.]

Re: Exhaust Manifold Finish

I would try this. I have used the product on an unrestored engine compartment that had some bare steel showing through.

http://boeshield.com/

I have also seen some guys using Slip Plate

Best of Luck!

[Joseph T.]

Re: Exhaust Manifold Finish

Kirk.
Remember, No orange overspray on the 67 Small Blocks. The exhaust manifolds were installed after the engine painting pocess.

[Kirk M.]

Re: Exhaust Manifold Finish

I think maybe it was the absence of "rust" on the manifolds that made the judge think they were coated. My point here is that in fact they are not coated with anything, so it is wrong to say that they are coated and deduct. If the actual issue is that I shouldn't WD-40 them to keep the rust off, I can stop that for the judging period I guess and let them develop so coloration? But seems goofy to deduct for NO RUST being present. I don't want to coat them with anything as my WD-40 experiment seems to work fine in keeping major surface rust from appearing. Remember, this is WD-40, so I'm not really oiling the manifolds either. This stuff just burns right off once the engine is fired up.


Kirk

[Tony S.]

Re: Exhaust Manifold Finish

I use PreLube 6 to treat my exhaust manifolds. I like the results. What you need to do if presenting your car with WD 40 or PreLube 6 is run the engine long enough to burn off the excess. After the exhaust manifolds get hot enough, my manifolds have a nice original looking patina. You didn't mention in your post whether you wiped your exhaust manifold on the judging field or whether you burned off the excess before presenting your car for judging.

Good subject.
Best,
Tony

[Kirk M.]

Re: Exhaust Manifold Finish

No, it was burned off way before judging. Actually drove the car 20 miles to the judging. That's why I'm puzzled by the comment of the judge that it definitely had been treated? I don't put the WD-40 on all the time, just a couple times a year seems to do the trick.

Kirk

[Gary B.]

Exhaust Manifold Finish; if not rusty, then coated

Kirk,

I suspect some judges use an "if-then" algorithm when it comes to exhaust manifolds: if they are not rusty, then they must be coated.

Gary

[Keith B.]

Re: Exhaust Manifold Finish

I have used the technique of soaking them with Armour All then put them in the grill to burn off the excess. Put them on tin foil so no direct flame hits the metal. They will smoke like crazy. When it stops you know they are ready. The finish looks as real as anything.

[Clark K.]

Re: Exhaust Manifold Finish

I think maybe it was the absence of "rust" on the manifolds that made the judge think they were coated. My point here is that in fact they are not coated with anything, so it is wrong to say that they are coated and deduct. But seems goofy to deduct for NO RUST being present. Kirk

My experience with Flight judges, in this case Mechanical Section judges, is that they look for some exhaust manifold rust and on some cars, engine paint overspray. Welcome to the aggravation of being stymied in trying to have a 100% points Top Flight car. The process has defeated many a good perfectionist.

I will always prefer to get a small originality deduction, because I don't want any rust on my manifolds. It is hard to explain to a Sting Ray admirer at a car show that you must leave rust on your manifolds ONLY for NCRS.
-Clark

[James N.]

Re: Exhaust Manifold Finish

Joe (9727): Regarding your post of 12/05/2010. What is the source of your information on the "no overspray on the 67 small block?" I'm several weeks away from bringing my 67 327/300 to a NCRS Chapter event for judging. Both myself and resto shop would greatly appreciate your response. Thanks.

[Mark D.]

Re: Exhaust Manifold Finish

As a wise old swamp dwelling goat once told me, "in rust we trust."

When I judge mechanical, which is quite a bit, if there is an absence of light rust, it would not be typical of a car that has completed the travel to its original selling dealer. Remember, we (NCRS) judge cars based on having completed dealer prep. With that in mind, it would not be typical to have zero evidence of light rust. With that in mind, if there is no rust then it must have a coating of some sort. It is not the responsibility of the judge to determine what coating it is.

If you didn't think there would be a residue of WD-40 enough to stall the rust, you wouldn't have gone to the trouble of applying it to begin with. Don't get me wrong, I like the idea and have done the same thing. Thing is, we are bound to judge at NCRS events by NCRS rules and I fully support that. I get the fact you don't want rust but, 'while in Rome...'

Regards,

Mark