Air Filter Oil Filter whats the difference?

LlamaJeep · 03-14-2008, 06:30 PM

This is my first attempt at a writeup so bear with me... Basically, I'm fed up with having to top up my oil, changing air filters and having oil dripping from my airbox 24/7 so I did something about it.

Heres a list of materials and what I paid:
-$2.59-An in-line pcv valve (shiny metal thing)
not sure what motor mine is for but any of them should work
-$6.99-a few feet of 1/2" heater hose
-$0.99-a 1/2x1/2x1/2" ribbed T fitting (grey plastic thing)
-$6.99-5 hose clamps that will fit 1/2"
-........a drill bit, forget the exact size, around 3/8 or so
-Free-1/2" bolt, must be short (2" or less ideally)
Total: $17.56 and tax

It was a really simple design, if you choose to do this, you can either use the really basic design that'll only cost you about $3 or you can do it the way I did...
For the basic design just put the pcv inline with the tube and call it a day (may have to shorten the plastic tube)

For the more intricate design I scrapped the old plastic tube that ran from the valve cover to the airbox and used a one way pcv valve and a little drip tube to collect any oil that makes it past the pcv.
All i did was ream out the plastic grommet that attaches to the valve cover, popped the pcv valve into it **(make sure its oriented so that it flows into the valve cover)

and then attached the hose onto the pcv valve.

I used a 1/2" T fitting to catch any little drips by having the one side face downward with a short piece of hose and a bolt to plug the end.

The other end of the T goes to the airbox, I used hose clamps on 5 of the connections just for some peace of mind.

I've only driven it for a day but so far my air filter is nice and dry

crusty75 · 03-14-2008, 07:03 PM

Nice work, good pics.

But if your PCV system is operating properly, you shouldn't have to do this. A poorly/incorrectly operating PCV system will cause lousy drivability, lousy gas mileage, and much increased engine wear. I would really encourage you to spend the time to fix it right. If you've replaced your PCV valve itself, and you're still getting that much blowby in the airbox, you more than likely have misrouted, disconnected, or leaky vacuum hoses. Could be as simple as a vacuum leak at the dipstick tube.

The only other thing that would cause blowby to that extent is a worn out engine. Have you done a compression check?

Anyway, you need to investigate further. Or Not.
Its your motor.

chriscisme · 03-14-2008, 07:04 PM

nice write up..now you just gotta figure out how often to empty that resevior

vtjeepthing · 03-14-2008, 07:08 PM

Nice write-up and good thought but, by installing the "new" PCV valve backwards may lead to more crankcase pressure resulting in more leaks. I agree with CRUSTY75 and would do a compression test. I'm curious to see how long the valve cover gasket takes it.

pat8942 · 03-14-2008, 07:17 PM

I agree sidestepping the problem doesn't fix the source of the problem, you're just treating the symptom and not curing the disease.

Quote:

Originally Posted by crusty75

Nice work, good pics.

But if your PCV system is operating properly, you shouldn't have to do this. A poorly/incorrectly operating PCV system will cause lousy drivability, lousy gas mileage, and much increased engine wear.

The only other thing that would cause blowby to that extent is a worn out engine. Have you done a compression check?

Anyway, you need to investigate further. Or Not.
Its your motor.

LlamaJeep · 03-14-2008, 07:19 PM

I replaced the pcv line at the back, and I'm 100% sure it has suction and it still oiled up my airbox. I know I have blowby but I just dont really care, I don't have the time/money to rebuild this thing right now and it still runs strong even with the rod knock or w/e its got. I'm just gonna run it till it blows and throw a newer 4.0 in there, this is just a bandaid to stop the oil bleeding all over my air filter

oh and to empty the hose i just loosen the clamp and slide the bolt out... takes like 30 seconds

DeclarationDay · 03-14-2008, 07:21 PM

If I were going to do what you did, I'd run a longer hose down, zip-tie it out of the way of the engine and let it vent onto the ground, instead of into that tiny reservoir. Not environmentally sound, I know, but neither is owning a Jeep Wrangler.

pat8942 · 03-14-2008, 07:31 PM

Google catch can and I'll bet you'll find you can make a vapor seperator with PVC pipe and some fittings.
I built two one for my air cooled beetle and one for my daughters 4.0 XJ and they work great.
BTW the XJ has over 270K and still runs strong.

Quote:

Originally Posted by DeclarationDay

If I were going to do what you did, I'd run a longer hose down, zip-tie it out of the way of the engine and let it vent onto the ground, instead of into that tiny reservoir. Not environmentally sound, I know, but neither is owning a Jeep Wrangler.

Lumpymayo · 03-14-2008, 08:08 PM

I think the oil is a result from too much blowback. Meaning the rings around your pistons are worn down and leaking oil as the piston moves up and down, But don't take my advice seriously.

**70sElvis** · 03-15-2008, 11:52 AM

My 91 2.5L had the CCV, not the PVC set-up and the (too small) vacumn line was full of crud. I took it off and sprayed cleaned and pressured air through it until I thought it was clean. Put it back on and it still blew oil into my filter. I ended up replacing the line and that took care of the issue.
But if your line is clean then it is definitely like Lumpymayo said. Your piston rings are allowing oil to push by them and causing too much blow-by.