Rear main seal leaking
#1
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Rear main seal leaking
My rear main seal was leaking motor oil like crazy. I think it's just the rear main seal worn out. So I have the clutch and rear main seal replaced. After all that, the rear main seal STILL leaking oil like crazy. My installer said it could be excessive pressure created at the crank case area.
It's a 02 Formula with 108k miles on it. I've headers, exhaust, FAST 90/90, SLP lid and that's it. IIRC, this problem starts after I installed the FAST 90/90. However, the engine didn't have any running issues, ie vaccum leak. It still runs strong every gear.
My question is, what and where should I check on it? PVC valve or worn piston ring? Do I've to take out the tranny and redo the rear main seal AGAIN? I've a track day on next Friday so I've get it fix ASAP.
It's a 02 Formula with 108k miles on it. I've headers, exhaust, FAST 90/90, SLP lid and that's it. IIRC, this problem starts after I installed the FAST 90/90. However, the engine didn't have any running issues, ie vaccum leak. It still runs strong every gear.
My question is, what and where should I check on it? PVC valve or worn piston ring? Do I've to take out the tranny and redo the rear main seal AGAIN? I've a track day on next Friday so I've get it fix ASAP.
Last edited by darknessxyz; 05-27-2010 at 04:31 AM.
#2
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It's remotely possible that crankcase pressures could be an issue, but highly unlikely. I'm not trying to discount your installer, but it's very possible he didn't install the seal right. Those are tricky to get in. I've seen several people over the years not replace them correctly, and I've even done it myself a couple of times way back in the day. It took a while to get the hang of it.
As for crank case pressures, if you are having an issue with that then put a Metco breather on the car. It will help release the pressure, and give your piston rings a break too. I recommend this mod on an LS engine.
As for crank case pressures, if you are having an issue with that then put a Metco breather on the car. It will help release the pressure, and give your piston rings a break too. I recommend this mod on an LS engine.
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Thanx for reply. I've some feeling he either didn't replace it or put it in wrong. However, he's specialize in LS engine, not just a normal mechanic. That's the reason why I go to him.
How can I check if the crankcase pressure is too high? Where to put that Metco breather in? Normally I use full size breather to replace the oil cap. Will an oil catch can helps also?
How can I check if the crankcase pressure is too high? Where to put that Metco breather in? Normally I use full size breather to replace the oil cap. Will an oil catch can helps also?
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Will my leaking problem goes away if I put in a breather, assuming my installer did the right job? If so, do I need to replace the rear main seal again?
#5
I hate to mention this BUT i'll bet its the center plug in the end of the crank. Its easily damaged if someone changes the pilot bearing with the wrong tools. Also could just be leaking because it was damaged or came loose. !st thing i would check before changing the seal.
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I did some tests today. I bypass the PCV valve and connect it directly to the intake. It still leak like crazy. I checked if there's any pressure coming out from the PCV tube, nothing. I even open the oil filling cap and let it idle, same thing.
Here's the symptoms, the oil will start leaking when it reach full operation temperature. If doesn't leak when it's cold. It's leaking between the bellhousing and oil pan. When it starts leaking, oil pressure drops from 60-40 on the dash gauge. It'll leak at idle and leak more when it shut off.
Is that a chance the PCV tube was stuck? I asked a local performance shop and they said put a vent system. What kinda vent system I should put in? Is it possible the rear main COVER screwed up?
Here's the symptoms, the oil will start leaking when it reach full operation temperature. If doesn't leak when it's cold. It's leaking between the bellhousing and oil pan. When it starts leaking, oil pressure drops from 60-40 on the dash gauge. It'll leak at idle and leak more when it shut off.
Is that a chance the PCV tube was stuck? I asked a local performance shop and they said put a vent system. What kinda vent system I should put in? Is it possible the rear main COVER screwed up?
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bump+ check the seal in the back of the crank,those cranks are hollow and the freeze plug seal will leak.They have had tsb from the factory for a while on the ls engine for this prob.when you change out the pilot you will sometimes from just excessive force move it just enough to break the seal.
#12
I might would check and see if your oil sending unit might be leaking and running down the back of the engine, After all you did just change the intake. You might get lucky.