Morris Minor Owners Club

Just about to start rebuilding an A+ engine after boring etc. It suspect that it has been left unpainted for some time, and need to prepare it both internally and externally before I start.
I have a blast cabinet just about big enough to take the block so would like advice as to whether it is advisable to blast the exterior or whether I should just use manual wire brushing to remove the rust please? I will of course thoroughly clean it all when ready and coat the inner block walls with glyptal before assembly.

Think I would be very wary about shot blasting the block for fear of not removing it all.

Alan

Yes, that is what was worrying me but I do have a air/degreasing gun?

Blast it and wash it, it’s what I’ve always done. As long as all the core plugs and oil gallery plugs etc are out it’s not a difficult job to make sure it’s spotless.

Eta: The oil pump priming plug had been removed and was put back so it didn’t get lost.

Personally I would never put any blast grit or similar material anywhere near the block. It is bad enough getting rid of machining crud/swarf from the inside of the block and oilways.

If you do blast the block with the camshaft bearings in place there is a good chance that the camshaft bearings will be ruined.

I always remove all of the oil gallery plugs and use a compressed air paraffin spray gun to clear the oil galleries and the inside of the block. Oil galleries are brushed through and the inside of the block is cleaned with a stiff brush. The process may have to be repeated several times until absolutely certain that no crud/swarf is still in the block.
Having screwed oil gallery plugs does help.

I would be extremely cautious about shot or bead blasting it, there are a lot of nooks and crannies where the media will stick.
If the block is a typically oily messy one, the blast media will very effectively stick to any soft residue and stay there, it will then find a way of re-introducing itself into the oil flow at a later date and wreck your engine.

Getting ALL of the blast media out of the internal oil ways will be nigh on impossible as well.

I design automated blast machines for a living, and can tell you that none of our customers that recondition engines would use abrasive or glass bead, some people use crushed walnut shell at a pinch, but the only safe way is to Soda blast it, the residue from that will just disolve in the water when you wash it.

Not trying to scare you here, just talking from experience. I have this afternoon put the top coat of paint onto my own 1098 engine block.
I cleaned it by hot washing it first followed by scraping and finally wire brushing.
IMHO that is all you need to do.

Phil

edit....Looks like Phil just beat me to it.

Thanks for input. I will stick to the manual method and not bother with the Glyptal,as I understand that unless the surface is absolutely 100% clean there is a serious risk of it breaking away and possible blocking of the oilways.
I do have oil gallery plugs fitted and gallery brushes.

Not sure what the paint finish is in my MM block it 'looks' like red lead!
Never found it in any other engines I've had apart but always thought what good idea it was as it creates a smoother internal surface which would be less likely to retain contamination.

Alan

remove head,turn upside down use scrapers parafin pressure wash do not under any circumstances try and wash the inside you will end up getting contaminents in oil gallerys.by allmeans remove sump after for cleaning. re john newton.

remove head,turn upside down use scrapers parafin pressure wash do not under any circumstances try and wash the inside you will end up getting contaminents in oil gallerys.by allmeans remove sump after for cleaning. re john newton.