Machine shop paint

ab777

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Getting my engine rebuilt right now at a machine shop, but for some reason the machine shop is insisting that they paint the engine, they obviously do not have the correct Chrysler turquoise engine paint. Apparently, they say that if they put the engine back together and I were to have someone to paint it the paint will not hold on to it.

I call this BS, as I don’t know how it will make the paint hold better. Because anyways when it goes back to the shop from them the plan was to completely have it sanded, primed, painted, etc. Any input on this or someone experienced something like that before?
 
I always paint my engines prior to assembly. The block (and heads) are fresh out of the hot tank and free of oils.
I use some generic red paint on mine prior to assembly and when it is all together I use the more expensive proper color paint.
On my pre-paint I bolt it all together (less internals) then paint it, that way all your mating surfaces and internals are protected.

Not necessary BS, I always felt bare cast iron absorbs oils.


Alan
 
Bare cast iron is "dry" and will flash-surface rust once it is outside the shop, in "normal air", by observation. Might not be obvious, but it can be there.

Let them paint it if it pleases them. Once in your possession and that paint has cured for a while, then YOU paint it like you want to. Rinse it in enamel reducer (to soften the skin a bit), lightly scuff the valve covers and such, then put your final top coat on the base color. No need to re-prime, just shoot color on it. After all, you are NOT painting fenders or hoods!

After that final paint has cured a good while, finish it off with some of the spray ceramic coatings of your choice for that lasting shine that will bead water and clean easier.

What I have mentioned might be a little "counter culture", but I kept one of my new car's engines looking good with a car wash soap, rinse, and hot wax for a long time. Just moving into more hi-tech formats now.

CBODY67
 
I always paint my engines prior to assembly. The block (and heads) are fresh out of the hot tank and free of oils.
I use some generic red paint on mine prior to assembly and when it is all together I use the more expensive proper color paint.
On my pre-paint I bolt it all together (less internals) then paint it, that way all your mating surfaces and internals are protected.

Not necessary BS, I always felt bare cast iron absorbs oils.


Alan
Totally understand where you’re coming from but one issue that I have been trying to explain to them is that the valve covers, intake, etc are in my possession. So at least I would need to have them paint them all together because it will be a paint to color match later as I have no idea what shade/color they used. Especially since they are not putting an effort into painting it the correct color.
 
Bare cast iron is "dry" and will flash-surface rust once it is outside the shop, in "normal air", by observation. Might not be obvious, but it can be there.

Let them paint it if it pleases them. Once in your possession and that paint has cured for a while, then YOU paint it like you want to. Rinse it in enamel reducer (to soften the skin a bit), lightly scuff the valve covers and such, then put your final top coat on the base color. No need to re-prime, just shoot color on it. After all, you are NOT painting fenders or hoods!

After that final paint has cured a good while, finish it off with some of the spray ceramic coatings of your choice for that lasting shine that will bead water and clean easier.

What I have mentioned might be a little "counter culture", but I kept one of my new car's engines looking good with a car wash soap, rinse, and hot wax for a long time. Just moving into more hi-tech formats now.

CBODY67
That’s what I thought too, I’d just let them paint it whatever shade of blue that pleases them and then when it comes back to the shop I’ll have it sprayed the correct Chrysler turquoise.
 
Is it in a machine shop or a paint shop?

Tell them no. Paint it your color your way. And you paint it immediately. It doesn't need extra coats of wrong color paint.
 
Is it in a machine shop or a paint shop?

Tell them no. Paint it your color your way. And you paint it immediately. It doesn't need extra coats of wrong color paint.
Exactly. I had to go back and forth with them until they agreed to not make a big deal out of the paint. I don’t know how it’s normal or okay to dictate what a customer wants or needs.
 
When it comes to a machine shop they need to stick to the machining and do their thing. Paint should be up to the customer. But some customers will paint the inside of the exhaust posts and get paint on the halve stems which can gum up the valve guides and make them stick.

But some guys will bring home the engine, store it in a swap and then complain that it rusted up on them.
 
Some shops will paint an engine "their" color so they know that it has or has not been tampered with after it leaves their shop. Not unlike a carb rebuilder putting some paint stripes on the screws to see if they have been tampered with by the customer, using the paint for warranty purposes.

Perhaps the machine shop might offer "engine paint" as a part of their service, BUT with the wide variations of colors for "OEM colors", might make more enemies than friends. So "Bring Your Own Paint" and they can use that?

When GM went from Corporate Blue to Corporate Black enine paint, warranty complaints of valve cover gasket leaks were drastically reduced.

CBODY67
 
another thing...since engine shops no longer use chemical hot tanks to clean their stuff and instead use water based cleaners, if it went in rusty it comes out rusty...and sometimes the some of the original paint survives...I've seen machine shops spray paint stuff cast iron grey right over the rust so you think everything's down to bare metal...they may not want their fresh rebuild handed to you looking like it just came out of the junk car after a trip thru the car wash
 
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I'm suspecting that the hot water spray cleaners still need some kind of "soap" in them, which is environmentally friendly. Back in the 1980s, a machine shop owner in a metro town told me the city was charging him money to empty his vat into the public sewer system. He said he told them "Why charge me for keeping your pipes cleaned out?" Of course, with all of the heavy metals and such in the vat sludge . . . another issue entirely. But the lye he was using did keep things cleaned out.

I'm suspecting the mix in the "soap" can be highly variable as to what's in it. At the owner's discretion. We have had several at the dealership since the middle 1980s or so, so we didn't have to send out engine heads and such to get them cleaned. Had to let things cool down before the door was opened! Engine paint was not a consideration.

CBODY67
 
Some shops will paint an engine "their" color so they know that it has or has not been tampered with after it leaves their shop. Not unlike a carb rebuilder putting some paint stripes on the screws to see if they have been tampered with by the customer, using the paint for warranty purposes.

Perhaps the machine shop might offer "engine paint" as a part of their service, BUT with the wide variations of colors for "OEM colors", might make more enemies than friends. So "Bring Your Own Paint" and they can use that?

When GM went from Corporate Blue to Corporate Black enine paint, warranty complaints of valve cover gasket leaks were drastically reduced.

CBODY67
I did actually offer to bring in my own paint but they didn’t seem to like it and didn’t want to do it.
 
As to the actual PAINTING PROCESS . . .

YouTube video at "Fast Monty's Garage". A nice video on engine painting, cyl heads in this case.

He details the products he uses and how he uses them. A bit more involved than normal engine paint situations, for sure. His methods and materials indicate a very high level of execution!! BUT with outstanding "show car" results.

Obviously, once the initial investment in his tools and liquids have been made, they can be used for other things, too. NOT just for engine painting purposes.

Look at it and see what you think!

Enjoy!
CBODY67
 
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