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I'm in the process of rebuilding my new 1955-235 to install in my 52-3100 the engine was setting outside on a farm when I got it, it was not locked up and ran fine after I changed the oil and ran some fresh gas than I put it in storage until now , the block and head have been baked and cleaned and I blasted the oil pan and lifter cover inside and out ,My question is there was some rust in the oil pan and the lifter cover so I blasted the inside of both and would like to paint them should I use engine paint or is there a paint for this that would be better??


Pete

Pete,

Are you asking about painting the inside of the oil pan and side cover (and maybe the inside of the valve cover)?

There really is no need to paint the inside of the engine, the oil will prevent any rust from forming once the engine is put into service.

Racers who "blueprinted" blocks used to use a product called glyptal, which is an electric motor internal case coating.
The only reason it was used was it made it easy to wash out debris after blowing engines up, and it sealed the casting pores so casting sand or casting material weeping out of the casting pores couldn't contaminate the oil, it wasn't used as a rust inhibitor, and probably not practical to use on a street engine.
I wouldn't use any conventional paint on those covers, if it starts to come off, it will really be a mess in your oil system!

I've built several race engines with painted internals, and the only way we found to keep it from peeling was to smooth the entire inside of the crankcase or the valve valley with a die grinder before applying the paint. The rough-cast surfaces simply couldn't be cleaned well enough to make the paint stick. We tried Rust-Oleum high-temperature engine paint and Glyptal transformer paint, and the Glyptal worked a lot better.
Jerry

See..I knew there was another old school "blueprinter" out there some where! Haa!! Haaa!
That makes two of us who know what Glyptal is!
Die grinding the inside of a block was a great job for apprentices!

Andy, I had a whole high school shop full of eager grinder operators! A couple of local racers at the Nashville round track sponsored my engine-building program, financing the parts, and giving the promising trainees places on their pit crews during the summer race season. We would do the engine machining and buildup, then run-test the engines on a water-brake bellhousing dyno. The engines hit the car already broken in, and ready to win races.
Jerry

Never understood the logic behind painting the inside of an engine unless you were going to put it on display. Any engine we used in the midgets or dragsters that I've worked on that had suffered any kind of failure was completely pulled down and meticulously cleaned using solvents then detergents and mechanical help like stiff scrub brushes and wire brushes for the oil galleries. Any engine that had any machine work done to it got the same treatment obviously. We never had these things back in the day, but everyone seems to have a pressure washer today. 3,000 lbs. of warm water and detergent is certainly going to blast any grit from even the tightest corner. If your casting has porosity then you have a bad casting. However, if your talking about the pores in the graphite contained in the matrix we are looking at nanometer porosity. I doubt if any particle on this level would be detrimental to the operation of an engine. Surface Stress relief by smoothing the internal block surfaces, sure I agree with that, but painting it, to seal the nano-pores nope, don’t make sense to me.

I worked with High Vacuum systems most of the three decades I spent at the Accelerator lab and we used Glyptal mostly for sealing vacuum and hydraulic pipe fittings and as mentioned, as a insulating varnish for binding fine wire coils and such. As a commercial electrician I'm sure you've seen Glyptal used in motors and electrical apparatus many times Pete.

And like Bill said, the earl is gonna cover the inside of the engine as soon as you light the fire. That’s gonna prevent any rust from forming, unless of coarse you “store it outside at the farm this winter”
Make it purty outside and don’t worry bout the inside buddy.

Note from a purest: Now, on that outside, make sure you use the Engine Gray (FS-359) from The Filling Station. You know by now that’s the correct gray for that engine, isn’t that right Woody???

Denny G

I was thinking,maybe the problem, that after I blasted the inside of the oil pan and the lifter cover and the valve cover that it could use alittle extra protection I was not going to paint the casting,So overthinking problem might have popped up.

Thanks ALL for helping we should get a overthinking area of the forum so we can release these thoughts and get on with building our trucks.

Pete

Denny, the explaination all the racers used for painting the inside of the block was "It helps the oil drain back into the pan". I never bought into that one, but I did believe there was some advantage to the idea of sealing any casting sand residue to the block instead of letting the oil wash it off and circulate it around. Mostly, it made the inside of the engine look good to the guy who was spending money by the pound to buy all those high-dollar parts, and I couldn't see a downside to doing it if the paint stayed put. Some things a professional race engine builder does are done just because the guy with the deep pockets expects it, whether the builder thinks it's effective or not. Remember the Golden Rule- - - -"The guy with the gold makes the rules!"
Jerry

Up until the last few decades Harley-Davidson used a paint on the inside of their aluminum engine cases because of the porus castings to help keep oil "weeping" through the case. I had a boss back in the 80's who also claimed that a rough casting was better for releasing oil from the walls of the engine. The little casting "tits" helped form droplets when the engine vibrated (no Harley vibrating jokes needed). I've used glyptal before, but for the most part I only see it needed as a sealer for a porous castings as mentioned above, good looks that you will cover up and to help seal any small particles onto the walls so they don't ever come loose. If you have properly cleaned your engine before and during assembly, I see no need for it. You must properly clean your engine before using it anyway, so I think, for the most part, it is a waste of money and time. No doubt it looks good though. The benefit, in my opinion however, is very small if at all.

Boy ain't that the truth. That "Golden Rule" sure holds true in all phases of racing. It used to be fun back when I was a kid but it's WAY to competitive for the average guy to get into now days. You have to make a business out of it or you can't afford it.

I would be willing to bet if you did a scientific experiment that once oil hits the raw casting that it's gonna drain back at the same rate as a painted casting. You're and old timer like myself, Jerry, well almost as old, I might have bought that residual sand thing years ago because I have seen sand trapped in corners. But that was all before the advent of the home pressure washer and like I said, 3,000 lbs will take off the end of your finger and I'd find it hard to believe that anything that wasn't casting could survive that.
Denny G

A light coating of paint won't hurt on the inside of the covers. Just give it enough to color it, that way the water vapors won't start the rusting again. A good powder coat will stay also. Use a brake cleaner or similer product that drys out the metal, then coat them. Joe