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Painting engine block

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TR3driver said:
BOXoROCKS said:
...a tip your guys might try,if it is bare cast iron,go over it with a propane torch. You will be surprised at the humidity that comes out of the surface.
Click to expand...
Of course, a lot of that humidity comes from the torch as well. I do the same thing myself, but IMO it's more to drive out any oil or solvent that is hiding. The initial fog left by the torch flame gives a nice indication of when the surface is warm enough (since the water no longer condenses on it). Works on mild steel, too.
Click to expand...

I "washed" my engine block and head with turpentine just brushing it all over and then painted it with a decent quality black enamel paint. The paint flowed very nicely and seems to be well stuck on.
while I haven't driven it allot yet it has heated up several times with no signs of being affected by the heat. The manufacturer of the paint said it is good to about 100C. If these engines are heating up to 100C on the outside there is a problem and it is not the paint job!
 
Tomster
According to the VTR Concours judging criteria all Triumph engine blocks were black. I got this from a General Information written up by Don Carter and Jeff Harris in 2005. Not that I am going for concours, however that is what the paper says and my original block and a friends are black and she has owned her 1975 since 1978 and not painted it.
FWIW
 
Norton47 said:
So, using POR-15 regular as a base would be all right and then overcoat it.
I see that the POR-15 web site rate regular POR-15 to 700 deg F for adhesion. So, I think that's what I will do.
I have some some hi temp black that I can overcoat it with.
Click to expand...

I don't think top coating over regular POR-15 with just
any other paint works very well. I think it would require their primer first to go to different top coat.

Maybe a little more research re what will work best.
Probably, if you like POR...and I do, by the way....
you might find a procedue they recommend coupled with
their engine paints would be the way to go.

Seems I wanted to do what you're thinking to do and they
said no. Don't know exactly why. Didn't make sense
to me why not.

Any way, either way, I find POR to be pretty forgiving
stuff, unless you get it on your hands. Please let us know if you've already done this and how it has worked
for you for all of us.
 
Norton47 said:
Jeff
Thanks, I was kinda figuring that water boils at 212 deg F so the engine shouldn't run much hotter than that.
My thinking was that the regular POR-15 would adhere well to the block as it still had some rust when it came out of the caustic soda tank. I have cleaned it with solvent, then Marine cleaner and have now used the Metal Ready.
This led to a bit of the white residue powder, which I have wire brushed off with a brass tooth brush.
I am going to give it a coat of POR-15 rust preventative paint and then top coat it, with a Black. I have some POR-15 black exhaust paint but that sounds like over kill for sure.

I think I will get some of the POR-15 self-etching primer and then top coat it.
Click to expand...

I think the white powder residue is something you want
left on the surface. It is a galvanizing, of sorts,
to protect from rust, and a reason for spraying on the
Metal Ready product from the POR line. Sorry. Hope you didn't work too hard getting it off.
 
Paul: Actually, also on this issue, I was interested
to know what product your shop painted onto your
head before you painted with this Ceramic Red paint.

I thought it looked rather clean and you said they
insisted this be done to protect from rust.

Can you find out what they used and its compatability
to other paint products?
 
Since everyone is talking about painting the outside I though I would throw painting the inside...I saw some paint somewhere where you paint the INside of the block, the paint is suppose to fill in pinhholes and make the oil run back in the pan faster and keep crap from building up on the inside of the block.
 
2wrench said:
Paul: Actually, also on this issue, I was interested
to know what product your shop painted onto your
head before you painted with this Ceramic Red paint.

I thought it looked rather clean and you said they
insisted this be done to protect from rust.

Can you find out what they used and its compatability
to other paint products?
Click to expand...

I found and use this stuff on bare metal of all kinds. It is not phosphoric acid based.

https://www.roadsters.com/gibbs/#paint
 
hondo402000 said:
Since everyone is talking about painting the outside I though I would throw painting the inside...I saw some paint somewhere where you paint the INside of the block, the paint is suppose to fill in pinhholes and make the oil run back in the pan faster and keep crap from building up on the inside of the block.
Click to expand...

Never used the stuff but maybe this is what you're thinking about
https://www.caswellplating.com/aids/glyptal.html
 
We used to paint the inside of the race engines with Glyptal, but found that unless you were starting from a new, unused, block, there was a slight possibility that the Glyptal could flake and get into the pickup screen.
Some of the Triumph blocks I've seen came painted black on the inside, from the factory.
Jeff
 
Hondo, my engine was painted on the inside. Saw it when I opened it up. Even after the cleaning process at the the machine shop it was still there. Your resoning above makes sense to me. I didn't have to add any paint to it.

Tinkerman
 
Hondo,
On the older Mercedes I've redone the engine block, tranny, steering box, dif were all internally painted with a red/orange paint of some kind. Sealed all of the castings and gave a slick surface.
I wish I new what it was as I never saw any wear or failure regardless of the cars age or mileage.
 
<div class="ubbcode-block"><div class="ubbcode-header">Quote:] Paul: Actually, also on this issue, I was interested to know what product your shop painted onto your
head before you painted with this Ceramic Red paint.[/QUOTE]

2wrench,

I can't get in touch with the shop until after New Years, but I remember that it was a common gray coating that went on the outside ONLY, to protect from rust forming. He did say that nearly all good shops who hot tank parts use it.

Bob also did advise that he NEVER puts anything on the inside of engines and that in doing so, one runs the risk of having something either flake off and block the pickup or become diluted with the oil and that brings a whole other set of problems to the table.

In all of my years in the service departments, I never saw anyone paint anything inside the engine and we built some very healthy racing engines for 1/4 mile drag racing and also Formula V endurance engines.

The inside of the engines are covered with oil. Why would they need any rust protection?
 
That was probably Glyptal, or a variant. All the Glyptal that I've ever used was that same color. It's primary use is coating wiring in electric motors.
Jeff
 
In regards to the white powder, I gave it a brushing with a brass brush. I didn't work it to hard.
I just have a hard time painting something that has a fairly loose powder on it.
I will call POR-15 to get more info on this subject.
I thought I also read some where in this forum that when doing body painting with POR-15 the consensus was to remove the powder residue. Oh well we will see.
I am posting some photos under a progress report.
 
Sorry, fellas, I do stand corrected. The white powder
coating is zinc phosphate; but, I do believe that
it is proper to leave it on and paint right over it,
even though it cuts against everything you ever
learned about painting before.

Actually, this is a strange kind of stuff. Example:
"Do not shake before application." Hey, most paints
you put into a machine and it shakes the dickens out of
it and its good. Not POR. You have to handle it like
an explosive. They do not even recommend pouring the
stuff; if you follow to the letter, you will "scoop" it
from the can and "place" it into the next receptacle,
etc. Kind of weird stuff. A little tempramental if you
tend to fudge, although I've both experienced good results
(and bad) from doing other than is recommended. Go figure.
 
Okay, the veil is lifted. Here is the web site.
Looks like POR-15 base is cool; topcoated by their
engine paint after Metal Ready.

https://www.por15.com/prodinfo.asp?grp=EPK&dept=7

Anybody hears differently on the zinc phosphate
coating being left on, please post for me.
Thanks.

I wonder what the big diff is on engine paint versus
high temp paint? Dang. Couldn't they make this
easier to understand?
 
Here is the Q/A on Metal Ready, which does have phosphoric acid and zinc phosphates in it. You need to remove the film prior to applying any type of paint or it will eventually lift or blister. I usually wipe it with a damp cloth before it dries, then as said before, scuff it and wipe clean.
It may take awhile, but it will lift your paint...Ask me how I know.

Also, care must be taken to not use self etching primer over phosphoric acid treated metal.


https://www.por15.com/Data%20Sheets/metal%20ready%20q%20and%20a%20sheet.pdf
 
Brosky said:
The inside of the engines are covered with oil. Why would they need any rust protection?
Click to expand...

They don't. The premise behind Glyptal is that is speeds oil drainback into the pan. Run a half quart over and forget about it.
 
If it was Glyptol then Glyptol is good stuff. I've never seen it flake off or fail and MBz used it liberally on the 1950's 300/190 SL's innards. I don't know if they cont. that into the late 60's or not.
 
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