Helo everyone, how are ya going? Just wondering if anyone can help me out here. Ive recently had the clutch changed out on my rodeo ( 2.6 ltr ) and had the rear main changed also. There was quite a bit of oil coming out before it was changed and it was the rear main that was leaking because the following had been changed trying to diagnose it..

Valve cover gasket
Head Gasket
Distributor o-ring
Front main

Now the guys have told me that the engine is possible over pressurizing the crankcase and forcing oil out of these seals. The engine has done 370,000 kms and it going very strong!!

It looks like i need to overhaul the bottom end, what exactly do i need to address this overpressurizing, just the piston rings from what ive researched, but i will do the usual main and rod bearings also. Am i right in thinking that changing the piston rings will stop this from happening, and just doing the bearings seeing as im there right? or wrong <img src="/forums/images/graemlins/confused.gif" alt="" />

Thanking you
Adam.

Well, what about your PCV valve? That is exactly what it is supposed to control...

I'd second on looking into the PCV. Remove it and it should rattle. Last winter mine became gummed up and my engine suddenly started making a huge mess - an engine that had never before been an oil dripper. WIth a clean PCV the problem was much improved. I washed mine out in paint thinner or similar solvent - new valves are fairly cheap (but not always available late at night).

Yep, tested the PCV valve. Removed from ebgine while its idling, and had a strong vacuum present. Just as the manual says. The ball inside does rattle and roll with it off the hose when i shake it. I've also checked the Oil pressure relief valve on the Oil filter adapter, and it does slide freely in its cylinder <img src="/forums/images/graemlins/smile.gif" alt="" />

Been told be other "reputable" people its the oil control rings that have collapsed, and its the combustion pressure that blowing the seals and pushing the pressure up ( or down, as in down into the crankcase ).

Anyone think thats the right diagnosis?

Regards.
Adam.

I'm not sure I'm buying it...

If you had that much pressure in the crankcase, enough to start blowing seals, I don't think the PCV valve or the dipstick would stay in place...

When you pull the PCV out, do you have massive amounts of blowby coming out the hole ? Is oil running up and out yer dipstick tube ?

Have you done a compression check ?

with 230,000 miles, anything is possible, and certainly rings fit the symptom. (although the oil control ring would seem to be the least likely of the rings to be the culprit here, imo) i just wonder if doing a ring job solely is the correct way to go on this engine, i.e. you are probably looking at doing a whole lot more once that baby is opened up.

HOWEVER, i'm talking generalities, and hopefully a more specific diagnoser with this engine will chime in....

what have your 'guys' done, diagnosis wise ? compression test? wet compression test? leak down test? these are some of the tests that can help isolate your problem.

and, btw, change that pcv valve, just in case <img src="/forums/images/graemlins/wink.gif" alt="" />


//bc

Theres no oil coming out of the hole when i take the pcv valve out, however there is a small amount oil coming out from the top of the dipstick.

Ill be changing out the pcv valve this weekend, as it could be faulty, thanks for your suggestion <img src="/forums/images/graemlins/kewl.gif" alt="" />

Ive always believed that worn piston rings could possibly lead to over pressurizing the crankcase. But darn it as soon as i change over a gasket, another one goes! Changed rear main, now front main leaks, changed front main, now oil adapter leaks, changed head gasket and valve cover too and now they are all leaking slightly, but the rear main it pissing out!

Should i just do a leak-down test and go from there?

Regards.
Adam.

A compression test is definatetly in order and if you have the ability to do a leak down that would be good too.

Check the hose for the PCV valve and the hose from the intake tube to the valve cover. If either one of those is clogged, a functioning PCV valve will do nothing to recirculate crankcase vapors.

Is the truck blowing blue smoke? If the oil rings were that bad, you would be loosing oil into the combustion chamber too.

Good Luck,
Michael

what i doubted was the remark in one of your previous posts above that

normally it would be the compression rings,not the oil control rings the compression rings are the two that seal the piston/cylinder so that the combustion gases don't blowby to the crankcase. if your mechanic is saying it is the oil control rings, i'd want to know more.

i would do the compression tests, both dry and wet. this will help isolate the cause of any compression loss to either rings or the valve train. a leak down test will also help in pinpointing the problem. this all assumes you do in fact have a compression loss, as your mechanics believe, and also assumes that it isn't your pcv valve system causing your over-pressure problem.

as others have pointed out, it'll be a lot easier and cheaper to make sure your pcv valve system is working even before doing further tests and diagnosis.

hth

//bc

Hi- what was the outcome of your engine problems? I am having the same exact thing happen on my toyota pickup with a 22r in it. I just finished rebuildng the engine in an attempt to fix this and other problems (it had a spun bearing as a result of oil starvation). I'm really at a loss for what to do because I've just replaced all the rings, bearings, etc. and permatexed all seals, only to have oil piss out of every single seal.
I did a compression test and got 125 psi, which is lw for a 22r. Still, I'm pretty sure the rings have not completely seated yet. It doesn't seem to be burning oil, just leaking from excessive crankcase pressure. I checked the pcv-- it seems ok. But there is so much pressure (and smoke!) in the crankcase that it comes out of the fresh air breather-- I.E. where the pcv is supposed to be taking air in. Any help would be great.