Oil system cleaning
 

I'm trying to get my oil tank, cooler and pipework clean before I put the enigne back into my 1971 911S. So far I have used mineral spirits which seems to work well to get most of the oily stuff out, however I'm now getting small bits coming out of the oil tank - is there anything more powerfull I can use, I've been at this for three days now and still have bits coming out, I must have flushed the tank about 50 times at least !....Also is there any easy way to clean the oil pipes that run down the rocker to the front oil cooler ? Thanks for any advice !

P.S. there is no evidence of any metal particles coming out - seems to be just dirt which crushes easliy between your fingertips.

Carb cleaner is both powerful and nasty, but it can assist loosening the crud buildup in the tank and in the external oil lines. Cap the openings with something impervious, pour in some cleaner and let soak for a day or so. You can also run a solvent-saturated cloth through the oil line (like cleaning a gun barrel). Rinse well with warm water and dry thoroughly. A hot tank (radiator shop) or steam cleaner is pretty effective too and your sig. other won't have to smell the after-effects of carb cleaner. Pay attention to the chemical solutions in the hot tank, and watch the blast pressure as some HD commercial units can create a fairly nice opening through weakened sheet metal.

Send the oil cooler to a company that does ultrasonic cleaning. Many aircraft engine rebuilders use these services. See if they clean using warm/hot solvent as the heat expands the cooler to let go of trapped particles.

Sherwood Lee
http://members.rennlist.org/911pcars

Just sent mine to Pacific Oil Coolers in CA.
Check out their website, www.oilcooler.com