spray painting crank case - opinions needed

jakepeewee

So I finally got some time off to work on my project engine for the SP3.
But now I need to decide how to spray paint the used (ebay) S4 crank cases.

Sounds really simple: spray painting the crank cases.
But I am not a very experienced mechanic and am having difficulties in deciding how to approach this.

I already got the spray paint and did strip the old paint off. The old bearings are still in there, got new ones to replace those.

As I see it the main options are:
a) Spray paint the completely installed cases
So I remove the old bearings, install the new ones and all the internal stuff (shimming the crank etc). Then clean/degrease and spray paint the cases.

But:
then I need to cover the bolts otherwise they will be painted as well. And I want to dry the paint by heating the cases to approx. 100 deg C for 30 min. Can't do that with the complete cases with the internals.

b) Spray paint the separate cases
So I remove the old bearings, put the cases in the dishwasher (rinse and dry them afterwards), spray paint the cases, heat dry the cases in an oven/stove, install the new bearings and install the rest of the stuff

But:
Is there a risk on damaging the paint when installing the new bearings (I never installed bearings in a crank case. Does it take a lot of force?). If I install the new bearings before painting, can I still heat the cases up to 100 deg C? Won't that hurt the bearings?

I am leaning to B, but hope to hear some opinions on this.

Regards,
Jacco

griff851

Heat the cases up to 160-180°C and chill the bearings in the freezer. The bearing drop out when you drop the cases or covers on the bench ( on to wood preferably) If your paint can't handle that it isn't very good and wouldn't have lasted long anyway. Note shit paint on Gt sports 1000's
The chilled bearings will drop in, but give them a tap to ensure. Only the outer race, and evenly, so it pays to make up drifts. If they cock on installation, don't try bash it in. Tap it out from the back or use a puller and chill bearing and heat cases again.

Bridgland

I got Protwins in Godstone to do a full strip of the engine and I took all of the parts to Wesley at Hi-Spec Coatings for blasting and Cerakote. This stuff is oven baked on and is meant to be very hard wearing and gives a great finish.

Have a look at my site for the before and after engine finish.

https://ducati888.co.uk/refreshing-t...rt-of-the-888/

there is a Cerakote company in the Netherlands https://ceracore.eu/

jakepeewee

Thanks guys for your response. The cerakote is indeed interesting, I'll save that for my next project since I already bought the spray paint.

I was also wondering what people use to heat these cases. Can't use the In house oven, the gases coming from the paint when heated are toxic.

Regards,
Jacco

mikesps

I use the barbecue for engine paint curing and bearing replacement, after eating the sausages of course.🙂