Blasting barrels and head CB750K0

[AshimotoK0]

Getting through all of the cycle parts for three bikes in the blast cabinet at work. Many happy hours spent, so far
I now need to clean up my very dirty and oily barrels from my CB750K0.
I can remove all of the oil and grime in the parts washer at work but I then I  need to blast them before painting. I am considering assembling and bolting  the head (with plugs in)  and barrels onto a scrap crankcase upper that I have, using spare, scrap cam covers, cam tensioner housing and blocking up the exhaust inlet ports  and bores/cam tunnel with some rubber sealing method. I would assemble with old but intact gaskets. I will then blast in the blast cabinet using fine grit at lowish pressure. What does everyone think? How does everyone else clean these up by blasting without getting blast media in the internal parts?

Ash

[martin_uk]

I am paranoid about getting blasting media inside engine as it only takes one piece to cause major damage and seems to find its way into places you didnt know existed

Your proposed method would certainly lessen risks.

[AshimotoK0]

I am paranoid about getting blasting media inside engine as it only takes one piece to cause major damage and seems to find its way into places you didnt know existed

Your proposed method would certainly lessen risks.

I was thinking of possibly pressuring the internals with compressed air and spraying all of the interfaces with soap solution to check for possible grit ingress points. I can't really think of another method other than wire brushing, which I did on my 400/4 way back but it never looks squeaky clean.

Ash

[UK Pete]

My method is to totally de-grease, then mask up all passage ways holes and gasket surface with good quality gaffa tape , blast the items  be it head barrells crankcases, airgun all loose blast media, and jet wash , then heat dry in oven and and blast with air again, if any trace of the blast media is left i repeat the jetwash  heat dry and air blast process
bung up any thread holes, and mask up all oilways ,

[Trigger]

A good way to block the oil ways is fill with silicon sealant and pick/blow out with a air line after blasting

[Saisei]

Some ingenious solutions here. Just wondering if there's a reason not to use vapour blasting other than cost?

[Trigger]

Some ingenious solutions here. Just wondering if there's a reason not to use vapour blasting other than cost?

Vapour blasting is only cleaning/finish and oxidation sets in quick on cast aluminum. Always better to paint in VHT to seal the engine.