Sudden Oil Leak: DD Series 40/DT 530E

Lostranger · September 07, 2015, 02:53:10 PM

I'm planning to drive the Gillig two-and-a-half hours tomorrow to paint the other side, but today I took a ten mile interstate trip as a check ride and to pick up supplies for the trip. Bus ran great, but when I arrived, the back was covered with oil, and oil was dripping from a number of places. The leak is not bad enough for me to see it's source, and it was not seriously low on the stick. I added a bit and drove home.

Any ideas where to look first? It did over heat yesterday because of a ruptured 5/16" hose from top of expansion tank to top of engine. Replaced it and another small hose this morning. That repair seems fine, but the heat could have damaged something. Engine ran great as usual.

I covet the collective wisdom.

Jim

luvrbus · September 07, 2015, 03:49:49 PM

Probably the high pressure oil pump or hose for the injectors "where art thou Kevin"

azdieselman · September 07, 2015, 09:42:47 PM

Crap, My crystal ball is out for repairs.

Your description is a bit vague. Wash the engine and then run it. Is it heaviest on the street or curb side?

Lostranger · September 08, 2015, 06:45:14 AM

Believe I've found the leak. Appears to be seeping where oil cooler bolts to block. Gonna pull that and see if a new gasket will fix it.

azdieselman · September 08, 2015, 07:52:53 AM

Remember to drain the coolant first.

Lostranger · September 08, 2015, 08:22:29 AM

Quote from: azdieselman on September 08, 2015, 07:52:53 AM
Remember to drain the coolant first.

Did not know that. Thanks.

Lostranger · September 12, 2015, 10:25:08 AM

Learned today that the reason the back of the bus gets covered with oil in a few miles has nothing to do with the seep around the oil cooler or the one at the alternator shaft. When I finally got my head back to the problem and did a proper oil level check, I learned that the crankcase was WAY overfull. I drained about 2-1/2 gallons before getting back to normal level on the stick. Not sure how I flubbed that check so badly last Monday, but I did.

At this point, I do not know what is getting into the oil or how. It does not appear to be water. That much water would surely make the oil look worse than it does. What I drained into a bucket has a faint cloud of gray, but mostly looks and feels like oil.

Monday I will find some place that does oil analysis and find out for sure what is contaminating. In the short term, I'm stumped. FWIW, the transmission fluid level is also high, and that fluid looks less bright red than it used to.

The oil discharge started after the engine overheated last Sunday. Obviously it's pouring out of the valve cover vent tube and the fan is sending it everywhere. Of course this could be a head gasket, but the engine still runs perfectly.

I'm open to any guidance or educated guesses. I'll post results after I get oil analysis. I'm not planning to do any more to the bus until I get that result. As always, thanks for your help.

Jim H.

LuckyChow · September 12, 2015, 10:51:47 AM

My first guess is fuel is getting into your engine oil. I'm not familiar with that engine to offer an educated guess, but possibly from an injector. In regards to the transmission, that's an interesting one. Did you check it with the engine running? If not, it will show over full on the stick.

Lostranger · September 12, 2015, 10:56:38 AM

Engine was off when I checked transmission. I have the alternator oil lines disconnected, so I cannot start it. I was just checking other stuff while I was at it.

LuckyChow · September 12, 2015, 11:05:22 AM

"Making oil" is a classic sign of a leaking injector. Someone familiar with the engine will chime in soon with an educated guess.

luvrbus · September 12, 2015, 11:45:53 AM

The fuel supply pump can blow a seal and fill the engine with fuel,I think Kevin is in Vegas for the weekend he worked for IH and likes those engines

they can be a real PITA for me so I call Kevin

eagle19952 · September 12, 2015, 12:26:33 PM

The oil discharge started after the engine overheated last Sunday.

What I drained into a bucket has a faint cloud of gray

Classic for water and overheating...have u looked under the valve cover ?

chessie4905 · September 12, 2015, 12:44:40 PM

While cold, crack open oil pan drain plug a couple of turns....if coolant drips/runs out, let it drip/run to see how much. If only oil re-tighten. You never want to allow a diesel to overheat; they aren't as forgiving as a gas engine.

luvrbus · September 12, 2015, 01:02:39 PM

That engine doesn't like to be idled either the ones the wholesale grocery people have here the oil samples always came back with excess fuel dilution till they finally stopped idling for long periods for the AC but that is probably not going to be your problem

Lostranger · September 12, 2015, 02:27:08 PM

Quote from: chessie4905 on September 12, 2015, 12:44:40 PM
While cold, crack open oil pan drain plug a couple of turns....if coolant drips/runs out, let it drip/run to see how much. If only oil re-tighten. You never want to allow a diesel to overheat; they aren't as forgiving as a gas engine.

I drained 2-1/2 gallons into a bucket. Does not look like water to me.