Cleaning fins on barrel

[murdo]

Anybody have a good recipe for getting years of burnt on oil off the barrel of a two stroke, mainly around the exhaust port.
 I have been soaking it in petrol but doesn't seem to be softening it at all. Was thinking of something chemical as I didn't want to sandblast it.
Any ideas appreciated.

[mark2]

nitromorse not the thin one

[33d6]

Hi Murds,

You're right. You don't want to sandblast it but there are other types of safe blasting methods using different media. Dry ice blasting or soda blasting with bicarb of soda  come to mind. "Vapour" blasting seems to mean different things to different people so I'd ask careful questions so each party understood each other before I committed myself there.

Old fashioned caustic soda will do it at home but I think it too hazardous for domestic situations, particularly if there are small children about.

I know you live in Oz, I could recommend an excellent firm in Melbourne. I no longer clean parts at home. Everything goes to this firm and it solves a lot of problems.

Cheers,

[murdo]

Thanks 33d6.
 I have sent a few bits to a bloke in Sydney for the wet blasting and they have come back brilliant.
This is just around the fins where the pipe goes, it has been leaking for a while and over time (50+ years) has baked the oil to the Villiers alloy. I have a glass bead blaster myself but was thinking there must be something chemical that would lift the gunge without etching the alloy.
No kids around here. 

[R]

If the cooked on carbon and oil is still gooey, then a good soak in kero or diesel will often shift it.
May take a while.  Needs to be stirred up regularly.

If its gone hard, then sawdust basting in your bead blaster will usually clean it off, without affecting the alloy finish.
Know any cabinet makers (or sawmills) ?  They are often pleased to give it away.  It may need sieving to take out any big lumps.  Mask off any places where dust may accumulate and cause problems later.
And clean thoroughly afterwards of course.

[33d6]

Interesting how everyone approaches the cleaning problem isn't it. I have a small ultrasonic cleaner  for the odd carbie bit and that's that. Otherwise everything goes for professional cleaning. They do a far better job than I can and I no longer have to store messy cleaning materials nor have a mess to clean up afterwards nor have to dispose of buckets of filth. It solves a lot of problems.
When I cost out doing it myself or paying someone else to do a far better job than I can there is no argument.
Still, each to his own and every one does what they are happy with. It's interesting to read how others approach the problem.
Cheers,

[murdo]

Well I got it clean. Has been soaking in petrol for nearly two weeks now and it still hasn't moved. Have been giving it a stir every day with a stiff bristle brush but no moving. I tried some oven cleaner, but it didn't do much. I mixed up some caustic soda and it didn't even fizz, so I added 'a bit more' and it really fizzed over the side of the bucket. It did clean it, but turned the alloy black. I tried several types of soaps, scourer's and more petrol but it was still black. Finally resorted to the bead blaster and all looks new again.
Poured the caustic into the muffler to soak off years of carbon.

[murdo]

Emptied the caustic out of the muffler today and flushed with a pressure washer. Came up like new.