Case paint removal Primary gear engines

[dmcoz]

Anyone have an efficient way of removing the original paint/powder coat ? from 81/82/83 etc primary gear engine crankcases ? the OEM stuff is on solid !!

 

[dartyppyt]

Bead blast it. But use black max slag instead.

 

[PEZBerq]

Paint stripper will work but takes a while

 

[Crashaholic]

If you blast with something coarser than beads be careful to not use to much air pressure. I've seen parts come out of the blast cabinet with pits especially on the early aluminum parts. Seems that some of those castings had tiny air pockets. I don't think the later magnesium parts had the same problem. Lower pressure with coarse medium takes more time but I think its less hassle than paint stripper. IMO glass beads are less effective on OEM coatings and at higher blast pressure they wear out quickly.

If you're dealing with powdercoat then paint stripper and a power washer is most effective unless its a part that can stand up to 500-600 degrees F then you can cook it on the bbq.

 

[jimspac]

I would not use Black Max or glass bead on magnesium or aluminum. I learned the usual way after glass beading the clutch cover on one of my TT500 clutch cover It really tore up the magnesium even at a pressure of 60 psi, Shells are much better and softer.

 

[dartyppyt]

I would not use Black Max or glass bead on magnesium or aluminum. I learned the usual way after glass beading the clutch cover on one of my TT500 clutch cover It really tore up the magnesium even at a pressure of 60 psi, Shells are much better and softer.

I use it all time on magnesium and aluminum 100 psi

 

[Crashaholic]

I never had a problem on aluminum or mag castings with #8 glass bead other than it taking a while. Medium recycled crushed glass at low pressure and at a low impact angle works best for me. I'll admit when used at a high pressure and pointed straight at the work it can do damage. I tried walnut shells years ago, it was to wimpy.

 

[pvduke]

spray on gasket remover works a treat too on any paint and some powder coatings.

super agro. wear gloves and glasses. i usually spray some in the cap and dab on with a small brush then neutralize in hot soap n water.

 

[justintendo]

spray on gasket remover works a treat too on any paint and some powder coatings.

super agro. wear gloves and glasses. i usually spray some in the cap and dab on with a small brush then neutralize in hot soap n water.

View attachment 86409

have you tried this on the swede black coating? that stuff laughs at some strippers..

 

[pvduke]

nope i havent. just kinda tossing it out there. i normally use it for gaskets but it is great at taking paint off all the stuff i've tried it on.

McKay Carb Dip/Cold Tank cleaner is another that just kills any kinda paint in seconds. at my uncles machine shop i had a 100 gallon cold dip tank with that in there for VW cases and alum 4-banger blocks and heads and that stuff ate every spray on coating ive ever seen right off it. stinks too! yuk!

 

[endurodave]

I surrendered for fret of damaging the cases trying to get the original coating off...... Ended up glass bead blasting, etch washed, and repainting.
Finished off with a 2-pack clear...... It turned out fine and is holding up other than where my boot constantly rubs on the clutch cover.

 

[Crashaholic]

Ended up glass bead blasting, etch washed, and repainting.

Exactly what I do. Alumiprep 33 etching wash works great even on magnesium.

 

[Bigbill]

Why remove the orginal black paint.? I’d rough it up with steelwool then put it out in the hot sun. Shoot it with a epoxy spray paint.

Try JEGS or brownells alumimum Hyde II

 

[Crashaholic]

Why remove the orginal black paint.?

Because its sand blasted from the front tire.

 

[justintendo]

Why remove the orginal black paint.? I’d rough it up with steelwool then put it out in the hot sun. Shoot it with a epoxy spray paint.

Try JEGS or brownells alumimum Hyde II

it looks like crap that way. its very hard to break the edges of where the coating is chipped. the factory coating is super hard, have you tried doing it?

 

[Bigbill]

Not yet but you guys got me thinking about it now. I have a #2066 case that’s been ridden or dragged behind a truck that needs paint bad. Now it’s either gloss of flat black? What you say?

With epoxy spray paint I heat the part to be painted then it calls for a single coat of paint don’t put on heavy coats. Better to do multiple coats.

 

[DaveM]

I used to put epoxy painted stuff out in the sun to dry, only to discover later that epoxy paint cures by a chemical reaction.

Enamel paint is the same.

Waste of time putting it in the sun to dry.

https://www.corrosionpedia.com/definition/463/epoxy-coating