Ok, we have both a disco and a d90. I was working on the disco today because it has had some lifter noise for a while now. I took off the valve covers to see if I could see anything. Well, what I found was a ton of sludge and bad oil buildup. The d-90 has always been well taken care of and has always had regular oil changes. The discovery was my dad's and for a good part of it's life, it did NOT have regular oil changes.
My question is: How can I easily clean out the valve/camshaft area without hurting the engine?? I have cleaned the valve cover itself and dug out quite a bit of the sludge already, but I am afraid that much of the sludge has gotten down into the oil passageways. Is there anything I can do with the valve covers off that will help clean all of that out? After I get it all back together, I am going to run some marvel mystery oil through it and change the oil/filter again after about 1000 miles.
Is the only way to get that area really clean just taking off the heads and say, steam cleaning them??
Any help is appreciated!