I have an old DR350 motor that I am rebuilding as sort of a hobby. What should I use to clean the head, valves, etc..?

 

carb cleaner works better than gas or kerosene imo.....use a bowl to capture while spraying this way youll be able to reuse for other little parts untill it evaporates....

 

Sand blaster and solvent. Some people use walnut shells for media. If you don't have a blaster then, like wheelinguy2003 said, carb cleaner works good.

 

hey doc...what are the walnut shells used for?

 

wheelinguy2003 there are many media types on the market. I used to be an aircraft mechanic and had the "fun" job of cleaning all of the cylinders when they came in. We had 3 different blasting machines. 1 was coarse sand. We blasted all cylinders and heads with that. 1 was glass and we did the tops of the pistons with that (taped up the ring lands). 1 was walnut shells and we blasted the ring lands of the pistons with those.
The walnut shells were very mild and will not harm aluminum. They sucked for taking heavy carbon build-up off though.
BTW, another thing that I have used is a small round wire brush on a die grinder. This works VERY well.