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Does anyone know of a low profile press in Crankcase vent filter for a 4.0L from an 88 Cherokee. I have measured the hole and it measures 1" but all the aftermarket filters are either 1 1/4 to 1 1/2 or 1 3/4... It needs to be press in so I dont have to used the factory rubber seal.
I went through the same dilemma last year. All the ones at the local shop were for bigger connections. I just ended up attaching about 5 feet of fuel line hose and running it down and back under my rig. 1990 Renix 4.0. Now all that oil blows out the bottom.
Well I'd rather not lose all the oil if I don't have too... There has to be some other solution to this problem... Why does all of the oil come out anyways? Is it really supposed to?
This is a common issue. The vents are clogged at the valve cover causing the crankcase to positively pressurize. Gets worse with age as blowby increases.
Remove valve cover, disassemble baffle, and clean all that crud out of there.
Take a tip cleaner and clean the orifice that hooks to the manifold vacuum line.
Reassemble all.
If you have any hoses which are junk, replace them. The hose used to come as an assembly from MOPAR.
So here is te deal... I have cleaned the valve cover after removing.. I'm pretty sure by baffles you mean the metal flaps right under the holes that are attached to the valve cover... I have cleaned these too... Also I have replaced all of the lines and I have verified patent of the line coming out of cover to the manifold and I have also verified that there is vacuum from the manifold. Any other ideas? Are there places in the head where oil is supposed to drain back thru? If so could they be blocked can I clean without removing the head? What other causes are possible?
i assume you fully removed the baffles and soaked or cleaned em up, ya said ya replaced the lines , cause that small straw sized tube clogs easily and if ya did replace that did you check the fitting that it connects to on the intake manifold?
if none of this is working you may have some bigger issues and may just have to run an oil catch-can for the time being
Haha... Thanks! My wife wants me to paint it but I think it just has character! As far as th inner baffles on the valve cover goes if I recall I didn't see a way to remove them so I just power washed the hell out of them from the top and bottom.. I wonder if I could extend them by riveting some met to them and make it harder for oil to get out... I thought about pulling the head and getting it hot tanked and rebuilt.. I'm sure this would fix my problem but its a real pain in the ass to take the manifold and intake off. There is almost no clearance btn the 4.0L and the firewall.. In fact the clearance I have was created with a BFH! What's your opinion? Should I be proactive and pull the head or reactive and just keep the oil filled and catch it in a can?
its been a while since ive had the valve cover off but i could have sworn there were 2 little bolts on each baffle cover.....ive worked on many engines since so i could very likely be wrong as for clearance its bloody tight but i believe it frees up a little with the valve cover removed just enough so that you can squeeze the head out of there, its one of the things im not looking forward to when i get off my ass and install my cam and have to pull the head for a port and polish and a clean
hard to say the info already posted should fix the blow -by issue but if there is some underlying issue then who knows
if your looking at the catch can idea they go from bare bones basic to pretty in depth just search the forums for "oil catch can"
do you still have that stupid vacuum line cluster block towards the front of the intake manifold, if so have you checked to see if thats clear or just by pass it, actually looks cleaner without that overpriced piece of plastic under the hood
This is a common issue. The vents are clogged at the valve cover causing the crankcase to positively pressurize. Gets worse with age as blowby increases.
Remove valve cover, disassemble baffle, and clean all that crud out of there.
Take a tip cleaner and clean the orifice that hooks to the manifold vacuum line.
Reassemble all.
If you have any hoses which are junk, replace them. The hose used to come as an assembly from MOPAR.
Take this a step further. Remove the flutes by removing the 3 screws on each one. Don't worry about the gaskets disintigrating. Chuck them. Cut 1/2" off the flute where it sticks down toward the head. Measure up 1" from where you just cut it off and drill a 1/2" hole on the rear side of each flute.
Clean up your cuts and holes before reassembly.
This was an unofficial way to help eliminate blowby into the air filter that a guy from JeepTech gave me years ago.
Be sure your CCV hoses are clear and not obstructed while you're at it.
