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Discussion Starter · #1 ·
I"ve had my car back from PFS for about a month. I've lost a quart of oil and found out my rear main seal is leaking. The shop mentioned too much crankcase presure may have caused the problem. Has anyone else had this problem after turbo installed? Also, how do I keep this from happening in the future. (2001, 57,000 miles, 14 psi)
 

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I am on my 3rd rear main seal. I blew one in august, it was replaced under warantee, but the problem did not go away because the Lexus techs did not seat the seal correctly. I wound up having SRT help me replace the seal again in October, and it has not leaked since.

Unfortunately, the oil in my bell housing fried my basically brand new rps 6 puck clutch, so I have been running around with a stock clutch with the rps pressure plate (no slipping, surprisingly!) and 400+rwhp for the last 3000 miles.

p.s. Buy the new RMS from Toyota, not lexus. They will charge you less for the same part.

C
 

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goldznnz said:
rear main seal? what does this do

and how hard for is it to replace? and is this a common prob for turbo owners?
It is located on the rear of your block and seals around the crank, keeping your oil where it belongs- IN the block.

Replacing it is a bitch, as you have to pull your tranny and flywheel, and will cost you about $500-700.
 

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:lol: thanks doublins, is there any way to improve this situation to prevent this main rear seal from giving, and is it really cause by too much crankcase pressure?


damn that sucks your clutch got screwed then! so clarify this: your on your stock IS clutch with rps pressure plate, right?
 

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goldznnz said:
:lol: thanks doublins, is there any way to improve this situation to prevent this main rear seal from giving, and is it really cause by too much crankcase pressure?
Well, it COULD be caused by that, but it could also be caused by a number of other things- if you boost your car cold, if you have a defective seal, if you have a problem that causes vibration in your crankshaft, etc.

It's never a good thing, though- in my case, I think that cold-boosting the car caused the first one to go bad.

damn that sucks your clutch got screwed then! so clarify this: your on your stock IS clutch with rps pressure plate, right?
Yes, I am on the stock clutch with rps pressure plate.

-C
 

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Mr. Negative
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i always wait till my oil temp gets to 60c to boost. Just a habbit. it usually takes anywhere from 5 to 15min depending on outside temps.
 

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rickmassingill said:
Thanks for the info. I've always made sure I don't boost before my water temp heats us. I do not have an oil temp sensor. Do I need one ?
so rick, if you don't mind me asking... where/who's gonna replace your rear main seal? when you mention "the shop" were you referring to pfs?
 

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rickmassingill said:
Thanks for the info. I've always made sure I don't boost before my water temp heats us. I do not have an oil temp sensor. Do I need one ?
I don't boost until the car is completely warmed up. Once the temp gauge stabilizes in then I will boost. Before that I am very careful.
 

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Discussion Starter · #14 ·
I live in Birmingham, AL. I don't think I will be taking it back to PFS. There are several good shops here that can do the work. I will wait for Peter to call me back before I do anything . Hopfully this will not happen again.
 

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Leak

Just got off the phone with Rick. I am not so sure he does actually have a rear main seal leak. There is no relationship between a rear main seal leak and boost. The crankcase is vented via the valve cover with a large diameter hose. Even cars with cracked pistons don't force oil through the rear main seal. On an automatic car it is not a matter of urgent concern as there is no clutch disc to contaminate. The oil will run out the bottom of the bellhousing and onto the ground. Possible cause may be related to the cold weather recently.

Pleased to hear from you Rick that the car is running so well.
 

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I ALWAYS make sure my car is warmed up before I boost. Very important.

After doublins mentioned his lesson learned to me, I'm even more on top of this. It's funny...when I go to work every day...I know the exact intersection where I can start boosting. That is almost always where the temp points straight to the left. Boost... :D
 

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VVTIS said:
If the rear main seal is leaking, where does the oil end up? On the ground? Or in the engine?
Well, the oil STARTS in the engine crankcase, where it belongs.

It leaks through the RMS into the bellhousing behind the flywheel. It then runs onto the spinning flywheel, which throws the oil via centrifugal force outwards, coating the entire interior of the bell housing with oil. The oil contaminates all of the parts inside the bell housing.

On an auto, you're fine if it's just a slow leak, as the torque converter is a fully encased unit.

On a manual, the oil gets on your clutch and causes it to slip, and to roast shortly thereafter. My brand new RPS 6-puck disintigrated in a matter of weeks, even though it didn't "feel" like it was slipping. The flywheel side was completely glazed over and not much material was left.

Eventually, the oil works its way down and exits through a small drain hole in the bottom of the bell housing, where it mates with the rear upper pan of the engine.

When your rear main seal goes, you will definitely notice an oil leak. You will have progressively more and more oil on the floor of your garage.

-Chris
 

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Mr. Negative
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if you are going by the temp gauge in the stock gauge cluster that isn't very accurate. My oil temp doesn't even register when that gauge seems normal. It takes about 10-15minutes of driving in 50degree temps to get the oil temp up to 60c. If you are in stop and go stuff it might be slightly less.

redline814 said:
I ALWAYS make sure my car is warmed up before I boost. Very important.

After doublins mentioned his lesson learned to me, I'm even more on top of this. It's funny...when I go to work every day...I know the exact intersection where I can start boosting. That is almost always where the temp points straight to the left. Boost... :D
 

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I do use the stock gauge. Actually, SRT said I am to wait until that needle lands at normal opperating temp (straight left for me) and add a few minutes. That is what I have been doing. Sorry, I mislead a bit. Not as soon as it hits left (because that would be about the the 2nd stop sign for me :lol: ). I know that is way too soon. I can actually feel the difference in the temp of the fluid...once it is warm. This goes for the tranny and engine both.

I wonder just how warm the oil really is when I wait that long. I hope long enough.


IS_Dude said:
if you are going by the temp gauge in the stock gauge cluster that isn't very accurate. My oil temp doesn't even register when that gauge seems normal. It takes about 10-15minutes of driving in 50degree temps to get the oil temp up to 60c. If you are in stop and go stuff it might be slightly less.

redline814 said:
I ALWAYS make sure my car is warmed up before I boost. Very important.

After doublins mentioned his lesson learned to me, I'm even more on top of this. It's funny...when I go to work every day...I know the exact intersection where I can start boosting. That is almost always where the temp points straight to the left. Boost... :D
 
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