Cleaning the crankcase

Colorado Greg

Senior Member
My car had the engine rebuilt in the mid 70's and has very few miles on it. I got the car from my father and it was ran every couple of years at best. After aquiring the '29 Coupe, i changed all the fluids etc... I got a little sludge out on the first oil change at 50 miles. Now that I have 500 miles on it I am thinking it would be a good idea to try and further clean the crankcase.

I have heard of putting in 3 qts of kerosene with 1 1/2 qts of oil to clean the crankcase. I have never done this and have a couple of questions.

Is it a good idea to do this?

How long do you run the engine with the kerosene in there?

Any feedback would be greatly appreciated.
Thanks!
Greg
 
Gary,

Id be a little reluctanat to run the kerosene mixture, although there may be some disagreements here! If you think there may be an issue with sludge why don't you pull the pan and have a look. It's really not that big of a job and you will know exactly what you have.
 
since you have very few miles on it since the rebuild i cant see it having to much sludge in it. if it werent for that i would say pull the valve cover and oil pan and clean it out that way. in your case maybe just do some more frequent oil changes with a detergent oil instead of waiting 500 miles. i would stay away from the kerosene method if you value your bottom end. i have used ATF but only for a quick run around the block then dumped it.
 
Kero doesn't have much viscosity to it. Plus you really don't know what is sleeping in the pan and valve chamber. And the diameter of the oil tube to the mains is exactly the size of a cockroach. A good winter job is to open her up and give her a good inspection and cleaning.

I drove a beater 76 Ford 6 that had a poor engine. I fulled it with kero and fired it up. Golly the thing clattered. About 30 seconds was all I could stand. I drained out much goop and she ran much better. I think the bath loosened some of the rings.
clem
 
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Kerosene or diesel won't remove the thick gunk on the bottom of the pan. If there is no layer of gunk, then it won't need cleaning anyway. The only way to know for sure is to drop the pan. But as Mitch said, with so few miles, I wouldn't expect much gunk.

When I first bought my 29 Tudor I drained the thick old oil, then screwed in a drain plug with an air hose connection. I dumped in a few gallons of diesel and turn the air on slow, so that it would bubble and agitate the diesel. After 30 minutes, I drained it and repeated this twice more. Then I put in new oil and drove the car 25 miles. At that point I dropped the pan and cleaned it the right way. There was an inch of thick sludge on the bottom of the pan that no amount of bubbling diesel would have cleaned out.

You could pull the dip stick and stick a long thin wood dowel down until it touches the pan bottom. Pull it out and see if any gunk is on it. That should be a pretty good indication of what's on the bottom of your pan. You could also bend a coat hanger 90* and stick it up through the drain plug hole, then spin it around on the pan bottom to see if it picks up any junk.
 
With respect to the previous advice I think you will not know what you have until you drop the pan, and the valve chamber cover. Be sure to remove the baffle. I wedged a 2x6 to spread the pan enough to remove the baffle. Also inspect and clean the oil pump. Stuff accumulates on the oil pump screen that you only see when you remove the screen. On the most recent motor it had been stored somewhere with the cap of the oil fill tube missing. Bob
 
Brentwood Bob is so correct in his directive. if you look at my avatar you will see what i found after replacing the oil pan.(the car was in a garage without a pan on the engine for years) after running the engine and discovering a sticky valve or 2 i pulled the chamber cover and found this little suprise.
 
The pan needs to be dropped before starting, this pic is of an engine that had been sitting for 15+ years, there was no sludge in the valve chamber, the oil looked dirty so it was detergent oil --when the oil is clean on an engine that has been sitting it is usually not detergent oil and all the dirt has settled ---more reason to drop the pan.

The dipper tray has many crumbs, some felt gritty, this engine had been stored with openings covered.

Flushing would get rid of most of the crumbs---but only after they have been churned up and gone through the bearings.
 

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Another reason to drop the pan and check Oil pump screen!

From 32 Service Bulletins on V8 but applies to 4 bangers also.
 

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hey thats all great advice but how about removing those baffles and cleaning what you can not see once the pan is dropped . I did the hanger trick, couldn't get through the gunk. I added about a quart of used oil but it didn't mix and only let a few drops through. the car has sat for many many years with its fluids left to thicken. the pan is out, as everything else. but what's the trick of removing the baffle from the pan ? i've tried to spread it but to no avail.
 
'29wagon,

Turn the pan upside down and insert about a 12-14" brass drift through the drain hole. Hit the baffle once or twice and it will pop right out.


Mike
 
Thanks for all the feedback. I'm not sure where I heard about using kerosene in the crankcase, but I was either mis-informed or mis-understood. Sure am glad I asked before dumping kerosene in my engine!

Thanks Again! :)
 
Thanks for all the feedback. I'm not sure where I heard about using kerosene in the crankcase, but I was either mis-informed or mis-understood. Sure am glad I asked before dumping kerosene in my engine!

Thanks Again! :)

I've heard the same thing, it's just that there are other ways to do it.
 
I 've heard the kero trick too from old-timers, but wouldn't try it with a low-mileage engine; better to drop the pan and open the valve chamber rather than risk toasting a good rebuild.
 
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