New Pump, No smoke, but sludge discovered in engine

[jspringator]

With my new pump and 2 new glows, I had a smoke free instantaneous start at 27 degrees this morning. Before it would have blown a smokescreen! The bad news is the mechanic found a lot of oil sludge in the engine. He said it didn't look like glycol contamination, which would be consistent with my fairly recent oil analysis. I did a search, and it looks like ronniejoe had a similar issue, discovered after blowup. Kennedy recommended Marvil Mystery Oil to clean things up. How much MMO should I use, and how long should I leave it in? Looks like the long term fix might be a larger oil cooler.

[john8662]

Where in the engine did the mechanic take his peek?

Just the intake ports (would be in that area doing pump R&R)?

For sludge in the engine I vote for a good flush of the engine oil. You can purchase engine flush in a can over the counter at your auto parts store. I'm too cheap for that, so I keep a 1.5 gal gas can full of diesel fuel (priming filters and oil flushes), I use the diesel in the crankcase for a flush.

When you're ready for your oil change (do this with hot engine), drain off 1qt of engine oil, or if your 6.5 is like most of them, it'll be 1qt low at 3k miles. Then add the diesel fuel directly into the oil filler tube until you have ~1qt added (you can check the stick). Start the engine and let it idle for 10 minutes, do not rev the engine, just let it idle. You can go as long as 15 minutes, but 10minutes is a good safe time amount. Then drain the oil completly and install a new oil filter, and you're good to go. This really does work!

J

[rjschoolcraft]

What about the fuel/oil mix that you leave behind in the oil cooler?

The larger oil cooler is a very necessary modification, IMHO.

[john8662]

fuel oil in the oil cooler?

Thats exactly the reason I use Diesel fuel, because you have to figure that a small amount of it ends up in the oil anyways. I don't feel that the residual oil left in the cooler is enough to severely reduce the viscosity of the oil.

[Dvldog 8793]

Howdy
Once a year or about every 15,000 miles I run a Qrt of engine flush(probably Diesel fuel :D ) And then drain it per instructions. I then fill the truck with cheapo diesel oil w/ new filter and run it for about 20min. Drop oil again fill with Delvac1 and a new filter/bypass and down the road I go. Sounds silly, I know, but it makes me feel good! :D I also have a bypass filter and run a 2qrt oil filter, on a regular change it takes just over 10qrts. This summer I'm upgrading to the big oil cooler.
My "84 6.2 normally makes it about 5-600miles before the oil looks black. That's just not normal for a diesel!
The sludge that I experienced with the new orange antifreeze was more like JELLY than sludge. I wonder if you do an oil analysis on the sludge?
L8r
Conley

[ogrice]

This engine flush technique I used for gas engines before, so take it in due consideration.

Replace 1qt of your oil with auto trans fluid. If the sump is 8qts, put 7qts 15-40, and 1qt ATF. The logic behind it; the ATF is highly detergent and is approx 20w oil viscosity. ATF doesn't have the combustion properties and additives like regular motor oil. The following oil change should be darker than usual because deposits and varnish that stick to the internal parts is being washed off. I've seen it work just like brand name engine flush additives.

[Hubert]

IIRC on the back of MMO it has a mix ratio for cold weather oil treatment. I am a little hesitant to use motor flush as it may be too harsh. I'd go get a case of the cheapest oil I could buy, some MMO, a couple of cheap filters. Change it back to back with the MMO ratio + a little more for "flushing" on the 1st change short idle and drain hot as you can stand it. I have let mine drain/ drip all afternoon on occasion. I recieved advice once to add 1 quart of synthetic oil to reg oil and it would break some stuff loose that dino oil did not. Note I have seen people who switch to synthetic on a higher milage engine get tapping/clicking lifters shortly there after from the synthetic oil cleaning out the gunk sealing worn out lifters.

If you do a flush I ditto back to back oil changes after flush. Just the oil in the cooler left over turns my oil black within minutes on a regular oil change. It bothered me at first so bad I did a back to back oil change then it took a day to turn black. :rolleyes: Live and learn.

I had to put a remote oil filter set up just for the vertical mount filters. I really dislike the dry horizontal filter on crank up at oil changes. I use to try to 1/4 fill them while I was wetting the seal.

[TurboDiverArt]

Personally I never flush the crankcase. Any time I have ever done it (on gassers) I've always developed oil leaks. My 6.5TD only leaks a drip or two between oil changes. I'm worried that if I flush the oil I'll develop a more severe leak.

Art.

[JohnC]

If your engine is really seriously sludged up, I'd be very careful about what I did to "correct" the problem. Too many times I've seen evidence of the following scenario: Engine is badly slugdged up or has not had an oil change in XX,000 miles. Owner changes oil or adds a quart of Doc Watson's magic motor cleaner. Sludge comes loose, plugs oil filter, oil filter goes into bypass and engine spins a bearing.

YMMV....