OK, my buddy'* Park Avenue has the 3800, so I think this is covered on this site.
well, it is pushing 200,000 miles, and I was telling him to run some kerosene through the oil for 5 minutes just before changing the oil, how much kerosene should he put in?

I use to put a quart in my cars pretty regularly and run it up to temp. Always thought it was a good idea. I stopped doing it after a 2.8L I had started knocking while I was letting it get hot. I can not link the failure to anything but thinning the oil, it was running just fine before that. The last thing an engine with alot of miles and wear on it is totally stripping the viscosity out of used worn out oil. I would suggest using a commercially prepared product and following the instructions. It can be a lot cheaper in the long run.

well, from what my dad says (about on old can of Motor FLush we have, uses one of those spouts you stab into it), it is just refined kerosene
but maybe hes wrong, anything you would recommend?

Your thread got my curiosity up, especially after having a horror story of my own. Here'* a page about it with more negatives then positives. Including a few like my own. I'm going to keep on what I have been doing, get it hot dump it all, and just re-add. The risk of parts going metal to metal because of thinning with solvent, And getting loosened sludge deposits stuck in the oil pump or smaller passage ways,.... isn't worth what little performance or cooler running you may percieve might happen. It isnt worth the risk.

OK then, thanks for the advice

I would just go to your favorite auto store and buy a quart of Rislone Engine Treatment, for my money it works great over time. Just use it to replace one quart of oil at your oil change. I have worked around cars for over 45 years and have seen a number of engines have bearing problems after people used kerosene. If the film layer between the metal of moving parts becomes to thin to actualy allow metal to metal contact it wont take very long to have a problem. My profession in in Metallurgy and I have seen what can happen without proper lubrication.

If oil changes were done regularly and the engine works well, then there should not be any sludge in it.

If there is sludge present, regular oil change intervals of 3,000 miles should clear it up over about 20-30K miles.

i wouldn't use any.