Tropicalbill

Mild sludge on crankshaft and everything that sat in old oil. 3/16" thick build up in oil pan which got thicker and turned gray.. Any tips on cleaning her bottom end? I've heard that additives could cause more leaks. She only has 50k but is 64 years young.

Sugar Bear

Either disassemble it to clean it meticulously, which I would try to avoid due to the low mileage or clean out everything you can get to with the pan removed using a scraper followed by a parts brush with a petroleum substance such as diesel fuel or kerosene. Don't use gasoline it's too flammable. It is important to remove anything knocked loose by scraping etc., to avoid clogging the oil pump pick-up screen.

Continue the cleaning process with frequent oil changes using a diesel rated 10W-30, change the oil alot and when the engine is hot so that the dirt in the oil stays in suspension coming out with the drain.

Avoid using aggressive solvents while running the engine, if the sludge is broken loose to quickly it may clog the oil pump pick-up screen.

Good luck and please keep the thread updated!!!

Tedd Thompson

If your sludge is gray/ whitish color there is a good chance that water has gotten into the oil at some time, hopefully no corrosion has taken place or a gasket has blown. Back in the day we would clean the valve train area the best we could with a brush and a putty knife then flush the lower end with kerosene or paint thinner, let it drain and dry then do a quart of Automatic trans fluid to four quarts of a diesel rated oil. Let it run for twenty-thirty minutes or so then drain(don't forget to drain the filter canister). You will be surprised of all the crud that you will see in the drain pan. Refill with what you plan on using in the future. you may stick a lifter the first oil change and keep a eye on your oil pressure guage in case you plug the oil screen. I don't like to push a engine hard with transmission fluid in the crankcase mostly because transmission fluid has great detergent properties but not so much lubricant value. If it mucks up and turns gray again you will need to find out where the water is coming from.... Just my experience.... Let us know how it works out... Tedd

oldcutlass

Personally, I'd just clean the pan. Reinstall and run some short interval oil/filter changes, minor sludge will clear itself.

Tedd Thompson

You are correct Eric, I misread the post and was thinking the pan was still on the car. I think I have two posts mixed up... My mistake..... Tedd

theold52

I know this is an old post but....Rebuilt the Hydra-Matic,as the car had sat 40 years. I did run the engine but not yet on the highway. Former owner had run it too. Bill of sale only, but California gave me plates last week.
Former owner ran 10-30. Blow by not bad. Pulled the pan, and Geez, the sludge. Pulled and cleaned the screen and pan. Changed filter element and filled with 30 wt Castrol High Mileage. Totally clean exhaust, but blow by got worse.
Today changed out the vc gaskets, cleaned sludge out. Back cylinder left side vales loose, so maybe lifters or cam. Not terrible though. Ticky sounding but smooth.
Used 2.5 quarts Castrol 30 wt, one can Rislone, 16oz Marvel, and 1 qt trans fluid. Fired it up. Oil pressure at 45lbs cold. Ran engine at about 1800 or so for 20 minutes, maybe more,checking oil pressure constantly.
Temp stayed at 180-185. Blowby cut by 75%. Loosened vc and oil came out. Good.
Started up again checked timing with strobe. Blow by still within my spec. Exhaust clean. Seafoam down carb, about 1/2 can, close to stall shut off. Had lunch, fired up, and clouds of smoke. Cleared right out. Blowby minimal.
I am getting ready to get to the highway with the old girl, but I don't think I will run this cleanout combo. Maybe four quarts Castrol 30 wt, and one of Rislone. Will see how it goes.
Just need to get those rings scraping through the glaze. Maybe it will be OK. Besides the ticking, the darned thing is very strong and sounds happy.

oldcutlass

I would not run that combo very long, I bet its very thin with low friction proofing. Make sure you have good oil flow through the shaft rocker assy.

theold52

Absolutely. I just went out again after dinner and fired up the engine. Pressure up to 45lbs, ran it to 180* kept it at around 1400 for 5 minutes.
Then shut it off. I will only do this a couple more times, then drain and use 4 qts 30wt and one of rislone. The reason I loosened the v cover bolts was to make sure there was oil coming out of the rocker area. There was.
I just want to help orifices to clear. Would never run this combo on the road. Too thin. Engine quieter now.
Really, an engine that has sat for so long needs a total teardown, inspection and rebuild. But it runs real well. I don't plan to do anything but local driving for now.
Seems to have helped quite a bit with blowby. When I have more $ and time to do it, I will rebuild. Robert