Oil leak

Greg, Before you go to far, check all the valve cover screws for any loosening that may have occurred. Wipe everything as clean as you can and watch and see if the leak returns.

I have no experience with main seals, but I am confident that some of the people here can address your questions.

remember to wave

paul

93 YJ

The oil pan itself can be leaking and running back. You might want to gently put a wrench on the bolts holding it on.

The drain bolt's washer is 'supposed' to get changed regularly and it can leak. Usually they don't get changed. I have a box of washers and change mine every couple oil changes.

The dipstick base can be leaking slightly and running back.

The oil filter base can be leaking slightly and running back.

Or it could be the rear main seal....

At least the rear main can be done in the vehicle...

Mike

86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail >

Front of the bellhousing is not a rear main seal. Check that valve cover again, very carefully..

Carl

Thanks Carl, will do. I am glad I found this forum!

Have a good holiday,

Greg Carl wrote:

Not really. A rear main will drip off the oil pan though, not off the bell housing usually.

You can take you Jeep out and play in the mud puddles splashing as much as you can, then drive it until the mud dries, stop and look carefully at the engine. Any leaks will show up plainly in the fresh mud.

If you take a clean rag and wipe the engine head at the back just below the valve cover or right along the valve cover edge and come away with an oil stain, you have found a leak. These only leak when the engine is running. Mine is bone dry back there.

Mike

86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail in '00 88 Cherokee 235 BFG AT's Canadian Off Road Trips Photos: N>

Hi Mike. Thanks for the in put. The oil is leaking down the back of the oil pan as well as down the plate thats behind it, or the plate at the front of the bell housing. Anyway I have bigger fish to fry seeing as though I discovered last night that my coolant is not circulating. It is in the shop as we speak having a new water pump put on. Thanks for the advice I really do appreciate it. Have a good day!

Greg

95 YJ Mike Roma> Not really. A rear main will drip off the oil pan though, not off the

Greg,

Old jeeps leaked oil(s) a lot.... the newer ones leak less.

Other, more experienced Jeepers have already mentioned the causes in separate posts but I'll condense them:

1. Back of the valve cover Overwhelming most often cause. Jeep changed the style and composition of the cover and gasket several times and only recently they seemed to figure out how to seal the engine. The fix includes getting the cover gasket flange and head *spotlessly* clean

1. Oil filter mount Not the filter but the base it screws into that is mounted to the engine block. There are several "O" rings in there. Jeep went through a spell where they used a poor choice in materials that would fail and leak. The repair is to replace the O rings which are about a dollar but the labor is a pain.

2. Oil drain plug gasket They eventually fail. You can get new ones at any auto-parts store. I've heard some cheap bast...err...jeepers have made them by cutting circles from coffee can lids ..... but I wouldn't know about that...

1. Oil pan Jeep went through a spell where they got a really good deal on pans made out of steel the consistency of tinfoil that would rust through. The first pinhole leaks would slow rusting in the rest of the pan by coating the bottom of the engine's pan in a layer of oil

2. Crankcase ventilation openings Sometimes there was a kit sometimes you needed to replace the whole valve cover... depends on the year and which opening. Pressure buildup would bulge or blow out seals and sometimes puke oil into the airbox.

1. Oil cap Sometimes they need replacement.

2. Front pinion seals Leaks on the driver's side

1. Steering gear and pump Driver's side

2. Transmission cooler and lines (with autoboxes) Un-maintained transmissions have brown fluid instead of red.

1. Emissions hoses They get brittle crack and split. They carry engine fumes to be re-burned and can leak through the cracks

11.. Rear main Dead center at the back of the oilpan or bellhousing.

They aren't in any particular order other than the valve cover which is the number one cause of 'rear main' leaks.

Diagnosis..... you have to either degrease the engine and recheck daily or spend the afternoon driving through the mud like Mike recommends.... dried mud reveals new leaks as wet spots.