diesel to clean sludge

[leroyd92]

a customer who i speak with often just got a 1983 454 motorhome that looks like its never had an oil change in its life... the valve cover cap is mushy and black and he said he would take pictures of the diesel flush attempt.

hes gonna put a gallon of diesel and a quart of 30/40 wt in the case and do a series of 5 minute start ups while he works on the Rv.

ive had really good results adding 2 quarts of diesel and oil to a engine with a stuck lifter or my boat motor that was neglected but never run almost straight diesel like this.

im anxious to see him tomorrow. the last change was~ 10000 miles ago and over 6 years ago!

he claims he did this all the time when he worked for a shop years back. i wanna see how fast it cleans or how many scarry noises come from the engine

 

[Lapham3]

More agressive approach than I'd care to try-hope it works out

 

[Nebroch]

Normal procedure, but I'd use quart diesel/gallon oil -ratio instead. And only idle, nothing else.

 

[3800Series]

Sludge makes a good sound dampener.

What might sound like a nice and quiet engine before can sound like a disaster afterwords.

 

[MrQuackers]

Diesel engine oil or diesel fuel?

 

[Doog]

Bad move. I would run synthetic 15w40 in it and change it often. Give it 25000 miles to clean up.

 

[mattwithcats]

I would run Rotella T6 or Mobil1 Turbo Diesel 5W-40 in it, change oil and filter every at 100, miles, then 500 for 4 changes...

 

[barkingspider]

Please keep this thread updated. I'm dying to see what happens to the engine. He'll, I hope it works lol

 

[Rand]

Originally Posted By: Doog
Bad move. I would run synthetic 15w40 in it and change it often. Give it 25000 miles to clean up.


Can you give us an example of synthetic 15w40 you would run for this purpose?

 

[Chris142]

1qt diesel to a gallon of oil.not the other way.

 

[Dufus2]

I have done this before with up to a 50/50 blend of diesel/motor oil and it really knocked the crud loose. It would be a good idea to let it soak and fire it up for just a few minutes, soak some more; repeat as needed. If it has an oil cooler, it may take 2-3 oil changes to get the solvents out of the lube system.

If the top end is all gunked up, it may be better to remove the valve cover and use a brush to loosen up all the crud from short trips.

 

[leroyd92]

Originally Posted By: MrQuackers
Diesel engine oil or diesel fuel?


i gallon of diesel fuel to a qt of straight grade...

he claims hes done this a lot on cars,trucks,boats whatever...

i did something like this to a iron duke. it worked amazingly well!

but i used "i believe" 1 qt 30 wt and 2 qt 2050 to an extra 3 qt diesel.

3 10 minute idles made the motor sparkley clean. pure diesel like this is either going to be great or scarry lol

 

[leroyd92]

Originally Posted By: Dufus2
I have done this before with up to a 50/50 blend of diesel/motor oil and it really knocked the crud loose. It would be a good idea to let it soak and fire it up for just a few minutes, soak some more; repeat as needed. If it has an oil cooler, it may take 2-3 oil changes to get the solvents out of the lube system.

If the top end is all gunked up, it may be better to remove the valve cover and use a brush to loosen up all the crud from short trips.


when i was in high school my automotive teacher helped my buddy with a 2004 ranger. it was neglected big time he suggested a 5 qt diesel cycle without whanging the filter... start it for a minute and do that 30/50 times. this kid went through the truck and left no thing unchecked. the oil/diesel he drained was black like oil. he ran one grade higher on the next oil change and drove it 50 k and sold it

 

[Shannow]

My first car was a heavily neglected Inline six, with 7 years on 20W50 dino (and Lord knows what before that), so badly sludged, that the rockers had their own tracks int eh valve cover...I scraped out a couple quarts of black gunk in rocker and sideplates.

Filled with Kero (no oil) and just idled it...drained out like black used oil, thick...did it again, then a couple of very shorts OCIS on rubbish oil.

Used a litre of diesel every OCI as an idle flush for some time after that.

I was young, and lucky...it worked, and did no damage...I'd do it again, but probably with diesel rather than Kero.

bobbydavro has an interesting point
http://www.bobistheoilguy.com/forums/ubbthreads.php/topics/3546847/Re:_Castrol_0W-30_Belgium_vs_C#Post3546847

Originally Posted By: bobbydavro
Ive know ultra high performance race oils use un-additised diesel as a base oil with rediculous levels of friction modifiers


I don't doubt that if you can get some FM in there, you could do a diesel flush quite safely at idle, multiple short periods, no load....now biodiesel, esterified edible oils could be amazing in such an application.

 

[Lapham3]

I had a '64 Falcon with the 170 six that was gunked badly altho only 30k miles. I recall 2 short idling flushes with about 1/3 diesel. It cleaned up pretty well followed up by shorter change intervals and worked out ok. I later got a speeding ticket in '68 for 89mph on I80 in North Platte, Neb so it held together fine until I traded for a '65 Pont GP. (Today I can hardly believe that speed and it holding together, after the abuse, with too few main bearings in that engine-stupid kid!)

 

[demarpaint]

Diesel as a sludge remover has been around forever. That's one method I wasn't brave enough to try though.

 

[leroyd92]

he took a few pictures with an older phone and you dont see anything other then a black hole on the rocker cover...

i looked at the nearest valve spring and it wasnt horrible like he said it looked............................

the only thing was the oil was very black. liiiiiiiiiiiike i cant see the lines black. the inside of the valve cover cap was identical like my boat motor was. he did pull the drain plug today and its been draining all afternoon.

 

[ARB1977]

My grand father ran kerosine as a flush in all his engines. My uncles used to say how spotless the internals were.

 

[Nebroch]

Local dealerships are using similar chemicals (Forte is one common brand).

It's quite stupid actually, first they increase OCI to 2 years/20k miles, and then "fix" the sludge/deposit problem with these solvents

 

[ET16]

The ratio suggested sounds dangerous to me. I wouldn't go more than a one part Diesel to four parts of oil.