Crankcase flush
 

I had an old welding machine with a perkins diesel in it. the fuel pump was located near the bottom of the block and had a primer pump lever on it. it was a diaphram pump.

at about 8000 hours, the diaphram got a leak/whole/whatever. diesel fuel started leaking into the crankcase.

it started slowly... I would check the oil and notice it hadnt burnt any, which was odd because it normally used a bit. then I would check it and see that it was a bit high... then a quart high... then filled right up!

I kept using the machine, as I was working long hours in a remote site it took a while to get the oil changed.

I went through the process again and eventually went and got a new pump.

the point I am trying to get at is, by the time this was all said and done, the inside of the engine was as spotless as new. no sludge or varnish to be seen!

I know that diesel is a solvent, so its not really surprising that it cleaned the inside of the engine.

I now have a 99 plymouth voyager with the 3.0 and a clacking valve train. from what I can find online these motors are prone to this as a result of varnish/sludge etc building up in an automatic valve lash adjusting mechanism.

Evidently the chrysler dealership fix is to simply substitute a quart of transmission fluid in place of oil to flush things clean.

I was thinking of subbing a quart or two of diesel oil and driving it for a day or 2

any suggestions?

tks'
bob

I have heard of the ATF trick to quiet those engines up. Alot of your treatments for gas and oil are kerosene or very similar. If I were going to do it I would use kero and do it in the winter when the oil could probally be a little thinner anyhow. Sea Foam has been working wonders for me in the fuel tank. I have yet to try it in the crankcase. I might just have to give that a shot.

That's basically all Rislone is. Aggressive engine flushes like that can cause a lot of trouble by breaking big chunks of stuff loose and clogging passages. I wouldn't do it.

The oil nerds at BITOG think highly of a product called Auto-RX.

thanks, I'm not really worried about chunks. looking down through the valve cover, the eng does look to have a fair amount of varnish but it looks like clean varnish if that makes any sense. I dont think there is much in the way of sludge.

what I'm mainly worried about is two things.

first, the perkins had mechanical lifters, the plymouth has hydraulic. I am imagining a scenario where I put too much diesel in with the oil and the compression within the lifters sets off the whole works.[dummy]

oops forgot... need air.

secondly I am concerned about the effect of the diesel on the seals, particularly the rear main.

couldnt see anything on BITOG about diesel.

cost of getting an new rear seal put in is probably about the same as getting a rebuilt motor and putting it in myself.

paid cash for the van so wth. will try it tomorrow.

btw, roads are all covered with salt and my new ctd (1st gen) is rust free, so I have to settle for having sit in the driveway for another 3 months:(

tks,
rjm

I've seen engine flush at the auto parts store. The label says to run it for like 10 mins in park or neutral then drain oil. You can probably run it for longer, but I dont think it's a good idea to put a load on the engine while this stuff is in the oil.

i wouldnt run the diesel for more than 10 minits. i know semi drivers do it every once in a while to keep sludge/varnish down. just do it every other oil change and see if it helps. running it too long make cause more problems with a thinner oil! my 2cents

If you insist on trying the diesel, just dump a quart in before you change the oil and idle the engine for 10 - 15 minutes. Do this with the engine hot. Don't drive around with the stuff in there.

I would think a diesel owner would appreciate a little clatter from under the hood. [laugh]

A quart of diesel or kerosene in it for a few minutes of running to flush it would be ok; or you could simply put in some good synthetic oil in it and run it and use a shorter drain interval than you normally would. Syn oil is high detergent and would clean the engine out as you drove it.

On that vehicle, the one thing I would be looking at closely is the automatic transmission. Every DC dealer is intimately familiar with those tranny's - inside and out.

I have used Rislone for years with great results, even in aircraft engines. It is a very good product for getting sticking valves unstuck, even exhaust valves stuck open. With a one gallon capacity sump, drain out one quart and dump in a quart of Rislone. Drive it for about 50 miles and drain out the oil. Install a new filter and oil. If the engine is realy sludged up, then do it again, but drive it gently for a few hundred miles. Drain it, using a new filter and oil. Never put more than a quart in at a time as you risk breaking off chunks of sludge and blocking something.

Okay,

changed oil, added 2 litres 5w-30, 1 litre atf-3, 1 litre diesel fuel.

started it up and let it run for half an hour... felt guilty so added another half litre atf-3.

got in, drove for about 650 miles, stopping to snooze while leaving the motor running to keep the heater running in sub zero. overall the motor ran pretty well steady for about 20 hours. about 6 at idle.

drained oil,was fairly dirty, replaced with 10w-30 even though the recommended is 5w-30.

voila, smooth and quiet. ;)

Good to hear. Anyone want to try that in their Cummins? lol.