oil dilution

[DAVID GAGNARD]

Originally Posted by olddog

Back when I was a puppy, the old dogs of that time advised you could add a quart of kerosene into you oil to clean sludge out. I did that several times with junk yard engines and used cars I picked up cheaply. I would let them idle about 15 minutes and then change the oil.

One particularly sludged up 283, I put in a Vega (I was building a 327 to put in it later), I added Kerosene and decided to leave it in to soak and clean until the build was done. I just started it to move it once in a while. After I finished the car, I forgot about the Kerosene and drove it around town for a day - maybe 50 miles. I destroyed the rear end on the way home. When it let loose, the engine likely hit 10K on a free rev (pegged an 8K tach). The engine seemed fine after that. I sold the engine to a friend who sold it to someone else who planned to rebuild it. The guy claimed all 8 rod bearings were spun. I always doubted it, as it ran just fine when I pulled it, but I will never know for sure. Bottom line, if you do try this trick. Let it idle a bit and then change the oil immediately. Don't repeat my stupid stunt.

PS
The guy did say the engine was clean as a new one. I had changed the intake, and it was hideously covered in sludge, so the Kerosene does clean them up. Wonder where it all went? Through the bearings?

There used to be a product on the market, might still be for all I know,it was for engines that see a lot of"city" driving and/or older gummed up engines,I used it once on my grandmothers car...This car had 50,000 miles on and probably never went past 3000 rpms,in her old age (90's) she only drove in town and averaged about 3000 miles a year....the car had a hard time getting much past 45 mph!!!!!!
Anyway,the directions said to get the car to operating temp for at least 10 minutes, pour the one quart stuff in the crankcase and let idle for 15 minutes, then change the oil and filter......it was supposed to help dissovle the sludge in the engine......
On the label it stated it was 95% kerosene,5% petroleum disstilates......it did seem to work though......
An old mechanic told me they used kerosene to flush the crankcase on engines that went under water....they would pulled the plugs and crank it over to get the water out of the cylinders and then pour in 4 or 5 quarts of kerosene after draining the oil, then remove the coil wire and crank the engine over for about 20 seconds and then drain the crankcase, then refill with oil,crank the engine with the coil wire off and spark plugs out till it built up oil pressure, then put the plugs in and start it and let it go.........