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Oil everywhere on my 4.0


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Since I'm pretty new to the "older" 4.0s......

 

How normal is this? Oil is everywhere on the drivers side underneath. The vent (PCV) on the rear of the valve cover is leaking badly. I can't seem to locate a new grommet for that. The dealer wants more than $20 for a little piece of rubber.

 

Here's a pic.

 

Image Not Found

 

Thanks,

Ron

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  • 1 month later...

I got the part from Orielly's about 2 weeks ago. It helped some but I still have a BIG problem. My entire driver's side frame rail is covered with oil just behind the airbox. My air filter is FULL OF OIL. I have to go buy a new one now it will hardly even move. It looks like oil is coming from the front hole (very bottom of the picture) in the valve cover and being pumped into my airbox. Any suggestions on how to fix this problem?

 

Thanks again,

Ron

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I read all 4 pages at NAXJA. Mostly talking about buying the parts or fabbing some up. Seems there is some baffles in the valve cover that could stand to be cleaned but ....Is it possible that much oil is going through the filter box and down to the wheel well?

 

I have the same exact problem. I sealed up the leaks at the top end and now my drivers side suspension and fender well are covered with oil. I was gonna build my new bumper this weekend but I think I need to fix this first. I am going through a quart of oil every 200 miles (2 days). I was thinking maybe the pressure is enough that its causing a leak under the exhaust where I can't see???

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ok, I think that we need to get some basic understanding of the CCV system in this thread.

 

The grommet and the hose in the rear are a metered vacuum leak. That hose is supposed to suck all of the vapors from the valve cover back into the intake.

 

The front, larger hose is to provide filtered air from the airbox.

 

What happens is this:

The rear CCV line get's plugged/the grommet stops sealing what have you, the system then reverses itself and the hose up front starts sucking out the vapors. Since that hose is so much larger, it also sucks up a bunch of oil.

 

You've got a few possible problems that cause this. The most likely is that all of the CCV parts need replacing.

The second most likely is that the tower/splash guards are all gunked up and interfering. Take the valve cover off and clean it.

 

The third and most unhappy situation is that your rings are worn and combustion chanber pressures are pressurizing the crankcase, forcing the oil out, only way to fix that is a rebuild.

 

So, do a compression check dry and wet. That will tell you what shape the rings are in. If they're in good shape, replace all of the CCV parts and it will likely be fixed.

 

This advice of course hinges on the fact that you have tested for and eliminated any other intake leaks.

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it's called time.

The CCV system is supposed to deal with the crankcase fumes, and those are a normal part of any engines operation.

 

Just figure that all of these trucks are almost 20 years old, the vacuum systems are falling apart and all of the rubber stuff under the hood is extremely suspect at that age.

 

I thought my 4.0 was on it's last legs because of my blowby problem, but a compression check showed nominal compression across the board.

Replacing the CCV parts was a complete fix for me.

 

Do a compression check, it's the best way to tell, unless of course you have a leak down rig.

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Ron, Sorry about the hi jack.

 

I have a new hose and grommets in the back going to the intake. I took the tube off and cleared it with the air compressor. No change. I will have to take the compressor to the rest of the ports. As well as pulling the valve cover. Anyone have pictures or know of any of the inside of the cover?

 

So by sealed up I meant new hoses in the back and RTV around the front grommet since the "Five Star" :roll: dealer here couldn't figure out how to order it.

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So by sealed up I meant new hoses in the back and RTV around the front grommet since the "Five Star" :roll: dealer here couldn't figure out how to order it.

 

Gotcha... just making sure that you didn't plug those hoses. 'cause that would've explained the miscellaneous leaking that would've developed. An engine's gotta breath, ya know.

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I don't think the thread got hijacked..... This is all very good information.

 

I will be working on getting my hoses cleaned or replaced. I'll also do a compression check on mine. I've got new plugs for it so I might as well check it.

 

I'll be checking back for updates!!!!!

 

Thanks,

Ron

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  • 1 month later...

I just installed all the new ccv lines from Napa.($50.00 and three weeks delivery to canada) Before, I would go find some oil in my air filter and would have to add a litre between oil changes. As soon as i installed the new ccy tubes (correctly) I have run four tanks of gas and have had to add one litre of oil at every fill up. Is there something else that i need to do. I have not removed the valve cover yet and cleaned it. Could this be the reason?

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