oil leak on xj
 

Question: I'm not sure if anyone can help me with this but any info would be greatly appreciated. After driving @ high speeds on the highway oil will leak out somewhere and drip onto the starter area. This does not happen every time that the vehicle is driven... only one in a while. just as quickly as it starts leaking it stops. The oil filter housing has been changed and it is not coming from there. If anyone has sen this before or has any ideas let me know.

Re: oil leak on xj
 

I had a similar issue recently...

I have a high mileage 4.0 after I fixed the valve cover leaks, I still noticed oil not only near the starter but also on my spark plug wires, and down the side of the block...

I determined it was coming from my dipstick tube... I confirmed by wrapping it with electrical tape dorve for a few days... no more oil.

But that was only a patch to my problem... which was a build up of oil pressure in the valve cover.

Excessive blow by and a plugged tube that normally would go to the air box caused the pressure.

hope it helps

Kevin

Re: oil leak on xj
 

Same problem here .

Re: oil leak on xj
 

Theres two hoses off your valve cover. The large one that goes to the airbox, is negative pressure. Meaning, this hose pulls fresh air into the engine. The other small hose attached to the Intake, is the vacuum (PCV). This little hose, is designed small to keep oil out of the intake. It is a bad design, but works. Take the little hose off, and clean it out. You can buy new ones from JEEP. Take it off, and show your parts guy what you need. This way, he orders you the right part. The port on the intake, occasionally gets filled with crud, this will cause same problem. Clean it out with a toothpick, and some intake cleaner.

Once you have that passage clear, and the problem persists, you have serious blowby. Go to a heavier oil, this will help.

Re: oil leak on xj
 

Well a smilar problem occured with me on advice of a friend I fixed the valve cover leaks, I still noticed oil not only near the starter but also on my spark plug wires, and down the side of the block.

But still the problem persisits

Re: oil leak on xj
 

How these leaks are caused can baffle you, until you understand crankcase pressure. When your pistons fire, if the rings are older, you get blowby. At highway speeds, or hard acceleration, it is increased. The PCV system , cannot keep up to these presures, if the engine is older. Oil pan, valve cover, timing cover leaks eventually start to appear. Problem is, as soon as the pressure has dropped (I.E back to idle, engine off) the excess pressure is gone too. Sometimes, bringing engine up to around 2500-3000 RPM in your driveway for a minute or two, will bring these leaks to light.

Re: oil leak on xj
 

I have the same problem, my question is how do I remove the pcv from the valve cover without breaking it, same with front one? Thanks

Re: oil leak on xj
 

wash the engine down with degreaser and rinse it .. in a responsible manner of course .. dry it up and take it for a good hard run .. i assume it's a 4 liter

likely suspects on the passenger side;

-valve cover gasket .. you'd probably have figured that out fast though
-oil filter housing .. change those o-rings
-distributor .. oh yea, oil can piss out around the bottom where it goes into the block
-oil pressure sender and fittings
-rear main seal .. if there's oil drops on your rear window you gotta change that sucker
-oil pan .. the pan rusts and gets soft and oil seeps through

Re: oil leak on xj
 

Is this a common occurance on high milage cherokees because mine is currently doing the same thing leaking after highway use but will stop leaking if not used or drivin very little. TRKRdave did you get your leak figured out????

Re: oil leak on xj
 

THe CCV Tubes that people are telling you about get brittle over time, so all you can do is be as careful as possible when removing them. If you are lucky like I was, you could look into a few wreckers and see if you can luck out and find some that have been replaced. The reason I suggest this is the system is extremely expensive at the dealer. The other option is to just tell people that tell you you are leaking that Jeeps don't leak, they mark their territory.