Topic: Engine exterior restoration advice.

[Jake750]

978 750f. Barn find. engine currently separated from frame and on a stand.

Engine exterior is pretty corroded. The 78 750f engines came out of the factory with a black coat of paint on them. I'm sure it looked good in it's prime but right now its just a corroded mess with paint flaking off all over. Don't even get me started on the engine fins.

I started removing the paint/corrosion with fine grit sand paper. Seems to be working well bit is slow. I have a wire paint stripper drill attachment but am afraid it might be too abrasive.

Anyone have any good advice/tips/techniques for cleaning and restoring a corroded engine that are realistic for someone working in their garage?

Ideally I'd like to just strip all the paint off and polish up the base metal, similar to how to earlier K model engines looked. giving it a coat of black heat paint is my plan B if polishing the metal isn't realistic.

Thanks!

[MauiK3]

Try paint remover.
You could make a soda blasting setup for better results.

[tlbranth]

I just did my '75 GL1000 engine. I put it on an engine stand, blocked all holes and sandblasted it outdoors. What I've found works really well is Home Depot's Silica Sand. It's nicely graded and has good cutting edges. First mask the covers you want to refinish smooth. After blasting, take masking tape off covers and blast with soda. Costco has decent sized bags of the stuff.

[Jake750]

tlbranth that thing is beautiful. What brand paint did you use if you don't mind me asking?

So to be clear, you used the silica sand on everything besides the covers, then used soda on the covers?? 

[maxheadflow]

Excellent Info..

[Doobie]

I just did my '75 GL1000 engine.

Cool bike!

[beemerbum]

I just did my '75 GL1000 engine. I put it on an engine stand, blocked all holes and sandblasted it outdoors. What I've found works really well is Home Depot's Silica Sand. It's nicely graded and has good cutting edges. First mask the covers you want to refinish smooth. After blasting, take masking tape off covers and blast with soda. Costco has decent sized bags of the stuff.

Outstanding motorcycle! Totally unique treatment of a "Wing"

[tlbranth]

tlbranth that thing is beautiful. What brand paint did you use if you don't mind me asking?

So to be clear, you used the silica sand on everything besides the covers, then used soda on the covers??

Actually, I blasted everything with sand. But my covers are painted. If you want smooth, natural finish covers I think you might want to soda blast them to keep them smooth. If you do sandblast, you want to make sure to have really good sealing over holes to the inside of the engine. I've soda blasted some stuff on my CB750 before and it works quite well but it gets pricey and the soda seems to kill the grass. Best if you use a blast box to recover the stuff.

All the green parts (engine and tin) were painted with the same paint:  https://tcpglobal.com/collections/hot-rod-flatz-paint-Olive-Drab-Green
Primer was an epoxy from Wesco.

My engine is water cooled and I'm not sure the paint would work on the higher temp CB head & block.