Topic: How to remove paint from engine crankcases?

[mazingerzeca]

The crankcases of my cb 750 F2 are painted black (original paint) and I want to remove the old paint (scratched) and paint it grey. I know two ways of removing the paint, but I have some doubts:
- Sandblasting: the paint is very hard to remove, so if I use sandblasting to remove it, wouldn't I remove the alluminum surface also?
- Chemical bath: I've been told that after two days in an "acid" bath the paint will be off, but wouldn't the acid bathe damage the alluminium in delicate parts such as crankcase bearing seats and others?
Both methods would be done in a shop, not by myself. They say that both methods are ok, but what does your experience on them says?
Thank you.

[kettlesd]

Prior to polishing my motor, I used a chemical gel-type household paint stripper - brush it on, let it sit for a few minutes and then brush it off. The paint came off a lot easier than i would have ever imagined.

You are right in guessing that sandblasting does remove material - thats the nature of the beast with some sandblasting abrasives, and they can leave the surface rough if not utilized properly. However, glass bead-blasting is far gentler than sandblasting and leaves the surface relatively intact.

Do a search on paint-prepping the motor - you will find a ton of info.

[Raul CB750K1]

Ignacio, I bought a gasket remover spray -CRC brand- to clean the mating surfaces of my CB350. I sprayed over the gasket remains to discover that the aluminium paint started to bubble. I used it recently on my Sanglas engine and it worked great.


Raul

[mazingerzeca]

Ignacio, I bought a gasket remover spray -CRC brand- to clean the mating surfaces of my CB350. I sprayed over the gasket remains to discover that the aluminium paint started to bubble. I used it recently on my Sanglas engine and it worked great.


Raul

That's great! Hope that it was in Spain, in an automotive shop. I will search for it. Thank you.