Bkoch97

I just bought a 1969 gtx earlier this month w 70000 original miles.. The car has sat for a very long time and when it did run I was told they didn't change the oil very often. My mopar mechanic (some crazy old man) is telling me to clean the crank case oht he has always used diesel witch sounds a bit rediculous to me.. So my question is how should I go upon flushing my crank case and what product should I use? Thank you!

Coronet 500

Welcome.

I have used WD-40 in the pan, run oil pump with a drill and turned crank by hand to clean oil passages and loosen lifters. Drain then do the same with thin oil, drain and fill with oil you want to run.

I have never added something to oil or replaced oil then started engine, like I'm sure some people might suggest to you.

RacerHog

I would just run AMSOIL Muscle car engine oil OR CASTROL GTX Hi-Mileage in it and run it... If you do anything else, you run the chance of washing all the sluge down in the crankcase and possably sucking it up in the oil pick up tube and lock up the oil pump or just sending all that junk threw the motor!!!
So, I say, ether take it apart to clean it or just, put good oil in it and run it....
Now if you want to push the subject.... I would use the SeaFoam product oil treatment or the old Resolon

https://seafoamsales.com/sea-foam-motor-treatment/
or