95 YJ 2.5l started losing/burning large amounts of oil practically overnight - JeepForum.com
Search  
Sign Up   Today's Posts
User: Pass: Remember?
Advertise Here
Jeep Home Jeep Forum Jeep Classifieds Jeep Registry JeepSpace Jeep Reviews Jeep Gallery Jeep Clubs Jeep Groups Jeep Videos Jeep Events Jeep Articles
Go Back JeepForum.com > Models > Jeep Wrangler Forums > YJ Wrangler Technical Forum > 95 YJ 2.5l started losing/burning large amounts of oil practically overnight

Introducing MONSTALINER™ UV Permanent DIY Roll On Bed LineFS: Wrangler RGB Multicolor Fog Light LEDs: Awesome EffectSavvy Aluminum Gas Tank Skid

Reply
Unread 10-17-2011, 12:18 AM   #1
m0jo
Registered User
1995 YJ Wrangler 
 
Join Date: Mar 2011
Location: Grande Prairie, Alberta
Posts: 9
95 YJ 2.5l started losing/burning large amounts of oil practically overnight

I have a 1995 YJ 2.5l thats my DD and it has over the course of last Friday to Sunday, gone from burning absolutely no oil to using a quart every 3 days. It has done 10+ 1200 km continuous drives this summer and has had no engine problems otherwise. The only recent change has been the 4.0l throttle body but I installed that about a month ago so I would imagine problems with it wouldn't just be starting now. The jeeps exhaust does have a noticeable oil smell when on the throttle, but does NOT smoke at all whatsoever. There is also no oil on my parking spot at home or at work and no leaks visible underneath.

Attempts to fix the problem this week involved changing the oil to 40 weight from 20 (was told if my seals/rings are worn out I can eek a little more life out of it by running heavier oil), it made it burn at the same rate but now it stinks like oil when I park and it didn't before, and also I pulled out the "CCV" (i think) line and fitting on the valve cover thats under vaccuum to the manifold to clean it but it seems to pass air just fine as does the line that goes to the PCV valve look-alike, there is a little bit of oil on my filter but it seems to be coming from the line that pulls air into the block from the top of the valve cover. It has had a very small amount of oil around that orifice and on the air filter since I got it 2 years ago though so I'm left clueless as to what it could be.

I could be wrong, but if I understand correctly my jeep will smoke if the piston rings/seals are gone right? Another thing I heard was to check the plugs but I don't know what for. Also compression is still good.

Any ideas are awesome.
Thanks

m0jo is offline   Reply With Quote
Unread 10-17-2011, 07:31 AM   #2
oldtime_ironman
Web Wheeler
1991 YJ Wrangler 
 
Join Date: Dec 2010
Location: 14304 Niagara Falls, NY
Posts: 2,540
It's good to hear the compression is good. This means the piston rings and valves are still good. I would suspect the valve stem seals though. On the plugs, you would be looking for oil fouling, usually a very thick black deposit.
.
oldtime_ironman is offline   Reply With Quote
Unread 10-17-2011, 07:51 AM   #3
laybackman
Bikini Bridge Inspector
 
laybackman's Avatar
1995 YJ Wrangler 
 
Join Date: Dec 2002
Location: Massachusetts
Posts: 6,085
Quote:
Originally Posted by m0jo View Post
I have a 1995 YJ 2.5l thats my DD and it has over the course of last Friday to Sunday, gone from burning absolutely no oil to using a quart every 3 days. It has done 10+ 1200 km continuous drives this summer and has had no engine problems otherwise. The only recent change has been the 4.0l throttle body but I installed that about a month ago so I would imagine problems with it wouldn't just be starting now. The jeeps exhaust does have a noticeable oil smell when on the throttle, but does NOT smoke at all whatsoever. There is also no oil on my parking spot at home or at work and no leaks visible underneath.

Attempts to fix the problem this week involved changing the oil to 40 weight from 20 (was told if my seals/rings are worn out I can eek a little more life out of it by running heavier oil), it made it burn at the same rate but now it stinks like oil when I park and it didn't before, and also I pulled out the "CCV" (i think) line and fitting on the valve cover thats under vaccuum to the manifold to clean it but it seems to pass air just fine as does the line that goes to the PCV valve look-alike, there is a little bit of oil on my filter but it seems to be coming from the line that pulls air into the block from the top of the valve cover. It has had a very small amount of oil around that orifice and on the air filter since I got it 2 years ago though so I'm left clueless as to what it could be.

I could be wrong, but if I understand correctly my jeep will smoke if the piston rings/seals are gone right? Another thing I heard was to check the plugs but I don't know what for. Also compression is still good.

Any ideas are awesome.
Thanks
If you are using oil then there are three possibilities;
#1 Someone is stealing your oil.
#2 You are leaking oil out through a seal but you see nothing on the ground
#3 You are burning oil.
Since your exhaust is smelling oil then you are probably burning it. BUT that means the leak is internal. My guess would be valve guide/seal.

What has happened to your oil pressure??
__________________
Chicks dig me.....Fish fear me

Getting older, I have developed some special skills. I have the ability to cough, sneeze, fart and pee at the same time.

"If we cannot afford to take care of Veterans, then we should stop making them."
David C. Wilker Jr. USAF (RET)
laybackman is offline   Reply With Quote
Unread 10-17-2011, 08:27 PM   #4
m0jo
Registered User
1995 YJ Wrangler 
 
Join Date: Mar 2011
Location: Grande Prairie, Alberta
Posts: 9
My oil pressure has always been 3 mpa (middle at idle regardless of temp) through 5 mpa (towards the high end but not all the way there since I got it, changing to the 40 weight made it go to about 3.75 or so at idle and the same as before at higher rpms.

I am quite confident there is no oil leaking out of the actual block into the engine compartment, the engine is very clean, about 3 weeks ago I went ocd cleaning my jeep and doing repairs because it gets to -50 Celcius for weeks at a time here in the winter so I can't work on it during winter unless I rent a garage. The only visible leak of anything is the clutch slave cylinder but I have a new one on order, should be irrelevant to losing oil though. Also I looked at the coolant today, as green as ever, no oil.

Is there any "tricks" to determining if the oil is actually burning through the valve guides or any where else? When you say valve guides are you referring to the ones on top of the head that the physical valves slide up and down through? How hard are they to change? I work on small engines regularly, just not full size ones.

Also the reason I say the exhaust smells like oil is because one of my friends following me to a trail head told me he smells oil but I myself have not smelled anything in the exhaust which would lead me to believe its only at higher RPMs or under load that it occurs.

Last edited by m0jo; 10-17-2011 at 08:29 PM.. Reason: added additional info
m0jo is offline   Reply With Quote
Unread 10-17-2011, 09:00 PM   #5
oldtime_ironman
Web Wheeler
1991 YJ Wrangler 
 
Join Date: Dec 2010
Location: 14304 Niagara Falls, NY
Posts: 2,540
Quote:
Originally Posted by m0jo View Post
Is there any "tricks" to determining if the oil is actually burning through the valve guides or any where else? When you say valve guides are you referring to the ones on top of the head that the physical valves slide up and down through? How hard are they to change? I work on small engines regularly, just not full size ones.

Also the reason I say the exhaust smells like oil is because one of my friends following me to a trail head told me he smells oil but I myself have not smelled anything in the exhaust which would lead me to believe its only at higher RPMs or under load that it occurs.
I'm not aware of any tricks other than to look at the intake valves and see what is on the back side of them.

Yes, the valve guides on top of the head, where the physical valves move. It's not difficult to change the seals, because the concept is simple. The labor can be a PITA because there's 16 of them, and you have to remove the valve springs and keepers.

You do not need to remove the head or anything, just use some compressed air to hold the valves shut - they make special adapters that screw into the spark plug hole and hook up to your air compressor.

The seals are just little rubber cups which push on and pull off the valve stems, located inside of the valve springs. They're fairly cheap.

At high RPMs or under load is exactly the time when valve seals will leak in fact. Especially since you are dealing with rubber parts, which are very old, and run in a bath of hot oil for their whole lives.
.

Last edited by oldtime_ironman; 10-17-2011 at 09:07 PM.. Reason: tricks
oldtime_ironman is offline   Reply With Quote
Reply

Tags
jeep , oil
Thread Tools


Suggested Threads





Jeep, Wrangler, Cherokee, Grand Cherokee, and other models are copyrighted and trademarked to Jeep/Chrysler Corporation. JeepForum.com is not in any way associated with Jeep or the Chrysler Corp.