4bangerjp.com
General Forums => The Mess Hall => Topic started by: Xpress on December 06, 2011, 03:44:53 PM
-
My oil cap is leaking. Pretty badly now, before it barely seeped anything over a whole month, now i'm up to 2 quarts of oil in 60 highway miles.
(http://img248.imageshack.us/img248/9560/mg0715.jpg)
got a brand new cap with grommet thinking it would solve the issue. Nope. I also noticed there is a bit of oil seeping into the air box. Just a little bit though, that wasn't there before. 89 TBI.
-
how much pressure is coming out of the large pcv hose? if all that is from the oil cap and not due to something else i suspect a lot of blowby, you can try and make sure the smaller vent is not plugged (i think the TBI has that as well, but not sure) but by the looks of it you're dumping a lot of compression.
-
That's gotta be blow by or else some other restriction that's causing the crank case pressure to rise then blow out. Isn't the oil cap on the front of the valve cover? Looks like it's blowing out the rear (EGR?).
-
looks like lots o blow by as sharp said. (and i though my jeep was bad) anyways I would check the pcv valve and line to make sure its not clogged (can possibly pull off the line to the pcv and make sure the line has vacuum and air should be blowing out of the pcv). thats the valve and line coming out of the front of the valve cover (near the fan) ideally fresh air is supposed to come from the air box through the big black thing near the back of the valve cover (has a series of filters in it that are probably really dirty by now) and then back out the pcv valve and sucked into the manifold.
edit: the egr is driver side of the tbi and don't see how that would spew oil. but cap is in front.
-
PCV valve is pretty new, when I put my thumb over the end of it while the Jeep is running it sucks pretty hard. I ran an old bike cable through the PCV lines and nothing is in the way, did the same for the crank breather.
I tried spraying the crank breather out with WD-40 and letting it sit for a while, seemed to clean it out, but when I re-assembled everything, nothing changed. It's definitely coming out of the oil cap, I've watched it. Nothing comes out of the crank breather or PCV.
It's almost to the point where i'm considering just gluing the oil cap shut and using the PCV hole to fill with oil.
-
Still have your Cat on. If so check it may be plugged. That looks a lot like what my under hood looked like. Also check the vent hose on valve cover, Pull that elbow out. Is it open or does it have a restrictor in it
-
I highly doubt the cat is plugged (nor part of the problem), it was replaced not more than a few years ago. Rev the engine and a hurricane of air comes screaming out of the exhaust like any typical 4 cylinder would.
As far as elbows go... Which are you talking about? The CCV and PCV are all clear as can be.
-
can it be that it is plastic cover and it's crooked or cracked there? I still say blocked breathers or blowby or both if the cover is good.
try adding another rubber gasket under the cap if you can (seen that done before on another vehicle but it had stamped steel cover).
-
How's the seal look on the oil cap?
-
Brand new oil cap, it's all good and rubbery (not hard like the old one).
I have read that the aftermarket oil caps don't fit correctly, and only the dealer part fits tight enough to seal properly.
-
Well going to grab some parts from the stealership, hopefully they fix the issue. Going to replace the new PCV, CCV, oil cap, and I've got vacuum tubing to replace the old stuff. figured as long as i'm at the dealer, might as well buy all dealer parts.
-
Howis it running, Done a compression check. Lastly is the PCV valve blowing any air.
Check the Valve cover on the inside the place where the PCV valve is at on the inside may be blocked.
-
Nothing below the PCV hole but valves and rocker arms, and a metal plate. no blockage. PCV sucks hard when I put my thumb over it. Haven't done a compression check, haven't had time to borrow the tool.
-
compression check sounds like a good idea
you could also take the cover off and do a leak test on the cap (flip it over and pour some oil in the cap cavity and leave it there - check later to see if it leaked).
-
This one keeps bugging me. Part of the reason is if the engine is right (No Bad rings or Cat) you could leave the cap off and not get that much oil.
-
This one keeps bugging me. Part of the reason is if the engine is right (No Bad rings or Cat) you could leave the cap off and not get that much oil.
does the tbi have a check valve on the pcv fitting? otherwise i would think that all the blowby would go in the airbox though, so i'm kind of leaning back towards a bad seating of the cap on the valve cover, speculating of course.
-
does the tbi have a check valve on the pcv fitting? otherwise i would think that all the blowby would go in the airbox though, so i'm kind of leaning back towards a bad seating of the cap on the valve cover, speculating of course.
Looks like a Check Valve type on the PCV valve. But it has two lines that go from the valve cover. Look at the 1st photo Front is the PCV valve what is it in the back.
-
on the tbi the pcv valve itself is the normal check valve type with the spring and slug, that goes to vacuum (intake manifold). the otehr connection (back of valve cover) that goes to the air-box has a series of filters in that big black canister. those filters can get extremely dirty and would prevent the oil from getting to the air-box (and air from air box to valve cover). so if those filters have never been cleaned or replaced they could be preventing the oil from going into the airbox.
my experience with that canister http://4bangerjp.com/forums/index.php/topic,8503.0.html
-
I know this topic is older but maybe I can get some help/answers, I have a 97 2.5L and found just a little bit of oil build up or collection in the throttle body and cleaned it out, also my air filter has just a little oil build up. Not a whole lot but enough to wonder why. But I thought a 97 4 banger does not have a PCV valve on top of the valve cover. Yet there is a hose from the air tube to the valve cover with a thinga magige there that is elbow shape. What is that? Could that be clogged. Or is there a different valve somewhere that could be causing this slight oil build up.? Can someone help me with this. Thanks
-
there's another sized fitting on the valve cover with a line going straight to the intake, both fittings (at valve cover and intake) and the line are prone to getting buildup, clean them well and make sure they breathe well (put a hose on and blow thru to make sure it is flowing freely after cleaning them).
with the engine at idle you should feel vacuum at the plastic elbow thingy you mentioned (even with the throttle partly open at 3000rpm for example you should still have vacuum and not get blowby gasses out of that elbow).
-
Ok sounds good, but to repeat and make sure I understand there is a another hose that runs from the valve cover to the intake which can build up oil and needs cleaning. Is this normal? And if that that elbow thinga migege on top of valve cover is not sucking in air at idle sould I change it ? Thanks
-
Ok sounds good, but to repeat and make sure I understand there is a another hose that runs from the valve cover to the intake which can build up oil and needs cleaning. Is this normal? And if that that elbow thinga migege on top of valve cover is not sucking in air at idle sould I change it ? Thanks
negative to changing the elbow, it's just a plastic piece with a big hole and nothing in it. the "air sucking" is a result of the air being sucked into the intake thru the other fitting (being behind the t/b you have vacuum at that line).
the other fitting is located towards the front of the valve cover (close to the thermostat), and yes to the questions related to that in your post above (it gets buildup and it is normal)
-
Wow love this forum, thanks alot I will start cleaning the hoses, O do I need to remove any fittings in the valve cover to clean or replace? and another question is do I just clean the vacuum hoses or replace them. Thanks for your experience/ knowledge.
-
i ran some brake kleen thru mine but had to cut one end shorter (EDIT: i'm referring to the plastic line here). the fitting you can remove if it's plugged badly or just run a thin steel rod or small screwdriver thru it to break the carbon, might as well remove it so you don't push all that junk back into the valve cover.
-
Sounds like a plan. I will try to get to it this week sometime. Many Thanks and Happy Wheeeling.