Scotty16

Rebuilt engine, has 8000 miles on it. Just found an oil leak yesterday. Looks like it was from the front of the engine. Checked the bolts for the oil pan on the front end of it. They were loose, so I tightened em to specs...yet it still leaks the same amount....Advice is for where to look next. Or what next to do

scottmphoto

Clean the front of the engine, get under there with a flashlight while it's running and see if you can spot where it's leaking. You should always try to diagnose the problem before you just start throwing parts at it.
Check the seal around the front of the crankshaft and the timing-chain cover. If you have to take it all apart to check the crankshaft seal, you might as well go ahead and replace the timing chain cover gasket while you're there (I made that mistake). The bolts on the timing-chain cover may just be loose as well.

Scotty16

LOL, tis why I was askin for advice Alrighty, Ill do that in the mornin

Scotty16

How do I get to the bolts to see if theyre loose, and where are they located?

DFlintstone

====

Radi

Are you certain it's motor oil? Could be power steering or a leaky trans cooler line too.
Those quick-leak fittings on the trans lines have their issues.

DFlintstone

I always blastr' good at the car wash then look really good with good light right away. The O rings in the adapter that connect to oil filter will harden and leak at some point. Cruiser wrote some stuff that helps VVV



I'd be looking up ABOVE first, and VERIFYING the source of the oil leak YOURSELF.
Everybody, who doesn't own or have to pay for or perform your vehicle repairs, loves to poke their noggin UNDER the Jeep and come out bearing the false bad news that your RMS is leaking.
Many mechanics, friends, and good old Uncle Bob seem to enjoy telling you it’s the rear main seal. Has a catastrophic ring to it, doesn’t it?
A simple leak at the back of the valve cover or other source could produce the same symptoms. You don’t need to be a mechanic to figure this out. If you have good eyesight and a dim flashlight, you’re good to go on your own. Don't jump on the RMS/oil pan gasket bandwagon right off the bat.

Almost any oil leak on your 4.0 is gonna drip from the RMS area for two simple reasons.
First off, the engine sits nose-up and any oil will run back to the RMS area. Secondly, the RMS area is also the lowest point on the engine. Simple physics and the old plumber's adage apply here. "$hit flows downhill".

Valve cover gasket, oil pressure sending unit, oil filter adapter seals and distributor gasket, in that order, have to be eliminated as possibilities first.
Revised 9-15-2012

CCKen

I was thinking (just for a second while I finish this beer); will a Jeep run while it's upside down? My thoughts are that if it will why can't the OP turn his XJ upside down and raise it up on a hoist (not too far), then run the engine and check for oil leaks. Any oil leak that originates from the top, such as the VC, would now be at the bottom, and any oil leak that's at the bottom, such as the RMS or timing chain cover, would now be at the top where you could easily see it. It sure would eliminate all the confusion about RMS vs. VC gasket leaks.

Thoughts...

Radi

Finished a couple so far, have you?

DFlintstone

The ccv orifice is only 2.4mm.......guess it might smoke a little until the fuel inlet figures out it's sucking air...

CCKen

I wondered what size hole that is. I want to make a hose/plug with a drilled orifice cap on it to take the place of the CCV tube at the intake manifold when running the engne with the VC off (oil flow to rockers, etc.).

Would this be that same size orifice for all XJ CCV's? I know the CCV fitting changed along the way. I think '97 & up were different than pre '97's. (?)

DFlintstone

Boy...I do have some Fsm's but going through, looking for things is not my favorite thing! (but for you), I'll look later. I believe there is also an anti-flash/backfire deal. Insurance against a backfire making your crankcase in to a bomb of sorts, I suppose.

I'll see if I can find diameter for post-97 later....

CCKen

Check that.

I just looked at the parts catalogs and the CCV fitting is the same for '94 thru 2001, so if that orifice size is the same for one of these years I'm all set. Thanks.

I think that anti-nuke feature you mention is the baffle inside the VC. You can't see the CCV from inside the VC so I guess the baffle would contain any backfire.

DFlintstone

OK, progress. First. It's 2.6mm for the (90) 4.0, and 2.2 for the 2.5. See in the first photo, includes anti back fire deal. It seems that also limits flow at high vacuum.


Then all I could find on a 99 is to check a sticker. I have my doubts it's on one and would hazard a guess that 4.0's might be about the same.

DFlintstone

Then all I could find on a 99 is to check a sticker. I have my doubts it's on one and would hazard a guess that 4.0 might be about the same.

I can't post the image of the page...it won't load...