Rear main seal help needed. Installed a new one = instant leak!
08-26-2011, 12:46 PM
#1
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Rear main seal help needed. Installed a new one = instant leak! Changed my clutch last week. Had an oil leak that was questionable from either the rear main seal or the oil sender. So...changed both.
In short, the NEW rear main seal is definetly leaking. About 1xdrop per hour after driving. Very upsetting, considering it's behind the #$%^ flywheel.
So, pulling the trans (again) tomorrow. Installing ANOTHER seal tomorrow.
Tips and techniques to make this the LAST rear main I install are very welcome. The one that's now leaking is a FelPro seal. Used the search and saw some peeps install these "backwards". I installed per the directions, so it wasn't "backwards". I pried the old seal out without damaging the rear cover, aligned the new one on the crank, and lightly tapped the new one into place with a soft hammer and socket extension. Lubed the outside of the seal with oil before install. The inner lip had a grease on it for the crank. Everything looked straight and no leaks...till I started the car.
So....did I do somethong wrong? Again tips and techniques appreciated. This is a real downer!
I'vwe thought of removing the entire rear cover this next time to install the seal. That leads to fear that THAT will also leak, since it has to be aligned to the oil pan......
BTW, I'm in the military and living in Germany, so running to Autozone to borrow a seal install tool, etc isn't an option for me!
In short, the NEW rear main seal is definetly leaking. About 1xdrop per hour after driving. Very upsetting, considering it's behind the #$%^ flywheel.
So, pulling the trans (again) tomorrow. Installing ANOTHER seal tomorrow.
Tips and techniques to make this the LAST rear main I install are very welcome. The one that's now leaking is a FelPro seal. Used the search and saw some peeps install these "backwards". I installed per the directions, so it wasn't "backwards". I pried the old seal out without damaging the rear cover, aligned the new one on the crank, and lightly tapped the new one into place with a soft hammer and socket extension. Lubed the outside of the seal with oil before install. The inner lip had a grease on it for the crank. Everything looked straight and no leaks...till I started the car.
So....did I do somethong wrong? Again tips and techniques appreciated. This is a real downer!
I'vwe thought of removing the entire rear cover this next time to install the seal. That leads to fear that THAT will also leak, since it has to be aligned to the oil pan......
BTW, I'm in the military and living in Germany, so running to Autozone to borrow a seal install tool, etc isn't an option for me!
08-26-2011, 03:51 PM
#3
Did you clean the crank area where the seal rides in?
I did mine a few days ago fel pro seal too. i bottomed it out in the rear cover
and added form gasket to the outside of the seal where it touches the cover and
some on the oil pan. Was crossing my fingers too since you here these horror
stories.
I did mine a few days ago fel pro seal too. i bottomed it out in the rear cover
and added form gasket to the outside of the seal where it touches the cover and
some on the oil pan. Was crossing my fingers too since you here these horror
stories.
08-26-2011, 03:58 PM
#5
A rear main seal cannot be put on backwards.....the bolts only line up one way.
Seal install tool...whats that?
We put a new tranny in my car last month..........so I decided to change my 9 year old rear main seal for the hell of it. I never did it before, so I replaced it while he prepped the tranny for install. Took like 5 minutes. I pulled all the bolts out, pulled the old seal off. Put the new one up there and put a bunch of gasket sealer stuff all over the bottom area. Then put the bolts back in. Then took the crank seal and slid it on with the little plastic ring on it. Tapped it a few times and it slid right on as the plastic ring got pushed off.
Done.
*****Only thing my tranny guy said before I tightened all the bolts......not too tight. He told me if you tighten them too much the gasket will leak. He's built a dozen LT1's and and rebuilt many LS1's........so I guess he knows.
.
Seal install tool...whats that?
We put a new tranny in my car last month..........so I decided to change my 9 year old rear main seal for the hell of it. I never did it before, so I replaced it while he prepped the tranny for install. Took like 5 minutes. I pulled all the bolts out, pulled the old seal off. Put the new one up there and put a bunch of gasket sealer stuff all over the bottom area. Then put the bolts back in. Then took the crank seal and slid it on with the little plastic ring on it. Tapped it a few times and it slid right on as the plastic ring got pushed off.
Done.
*****Only thing my tranny guy said before I tightened all the bolts......not too tight. He told me if you tighten them too much the gasket will leak. He's built a dozen LT1's and and rebuilt many LS1's........so I guess he knows.
.
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08-26-2011, 05:44 PM
#8
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There might be a groove in the crank where the seal rides. I've never done a rear main on an ls but this is a common problem on any motor. One piece of sand or whatever gets in there and makes a nice little groove in the crank. pita. They make a sleeve to fix it.
08-26-2011, 05:52 PM
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Appreciate the responses. I don't think it's the crank plug, as the leak got much worse after installing the new seal (before it was a drop per week, not a drop per hour). Will check either way though.
Sounds idiotproof. Guess I'll pull the cover this time, check the crank for grooves, install the new seal and cover seal, RTV the snot out of everything.... and then run it without the trans installed to see if it leaks to at least save pulling the tranny a 3rd time
Anymore tips or pointers are greatly appreciated.
Sounds idiotproof. Guess I'll pull the cover this time, check the crank for grooves, install the new seal and cover seal, RTV the snot out of everything.... and then run it without the trans installed to see if it leaks to at least save pulling the tranny a 3rd time
Anymore tips or pointers are greatly appreciated.
08-26-2011, 06:31 PM
#11
CANNOT be put on backwards.
This is exactly what I ordered......Rear Main Seal kit. Felpro.
http://www.rockauto.com/catalog/moreinfo.php?pk=447129
.
08-26-2011, 06:34 PM
#12
Mine isn't leaking after 1 month, not a drop.
.
08-26-2011, 07:47 PM
#15
When you put the crank seal on (the round one) permatex the outside of the seal where it sits in the cover just a thin layer and put it in evenly. Do not lube the inside of the seal where it slides on the crank. Make sure the round seal is facing correctly and not on backwards many people do this.
08-26-2011, 08:35 PM
#17
Another mistake I see people remove the white plastic thingy from the center thinking its there just to keep it round from GM after reading an article from GMHIGHTECH that incorrectly stated that exact thing. That plastic piece in the center is actually a TOOL to help you slide it on the crank perfectly. Like a reverse piston ring installer. And it certainly works fantastically well and makes it all much easier.
08-26-2011, 10:09 PM
#18
No, that's the rear cover. The rear main seal is what you are calling the crank seal. What I read a lot of people were doing was to put oil on the inside of the round seal. DONT. Also, they aren't cleaning the crank where the seal sits. That ALSO needs to be dry. From what I understand, there needs to be friction between the inside of the seal and the crank so that a thin teflon coating from the inside of the seal, can be rubbed onto the crank to create the seal. Any oil, and this can't happen. I would also put silicon between the outer part of the seal and the rear cover. extra insurance.
Another mistake I see people remove the white plastic thingy from the center thinking its there just to keep it round from GM after reading an article from GMHIGHTECH that incorrectly stated that exact thing. That plastic piece in the center is actually a TOOL to help you slide it on the crank perfectly. Like a reverse piston ring installer. And it certainly works fantastically well and makes it all much easier.
Another mistake I see people remove the white plastic thingy from the center thinking its there just to keep it round from GM after reading an article from GMHIGHTECH that incorrectly stated that exact thing. That plastic piece in the center is actually a TOOL to help you slide it on the crank perfectly. Like a reverse piston ring installer. And it certainly works fantastically well and makes it all much easier.
So the gasket thing with the 12 bolts that fits onto the back of the block UNDER the rear cover......is called the rear cover seal?????
lol
Anyway....I accidentally knocked the plastic ring out of the crank seal when I grabbed it. It slid right back in. We didn't clean the crank or oil anything and all is good.
.
08-27-2011, 09:05 AM
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A rear main seal cannot be put on backwards.....the bolts only line up one way.
Seal install tool...whats that?
We put a new tranny in my car last month..........so I decided to change my 9 year old rear main seal for the hell of it. I never did it before, so I replaced it while he prepped the tranny for install. Took like 5 minutes. I pulled all the bolts out, pulled the old seal off. Put the new one up there and put a bunch of gasket sealer stuff all over the bottom area. Then put the bolts back in. Then took the crank seal and slid it on with the little plastic ring on it. Tapped it a few times and it slid right on as the plastic ring got pushed off.
Done.
*****Only thing my tranny guy said before I tightened all the bolts......not too tight. He told me if you tighten them too much the gasket will leak. He's built a dozen LT1's and and rebuilt many LS1's........so I guess he knows.
.
Seal install tool...whats that?
We put a new tranny in my car last month..........so I decided to change my 9 year old rear main seal for the hell of it. I never did it before, so I replaced it while he prepped the tranny for install. Took like 5 minutes. I pulled all the bolts out, pulled the old seal off. Put the new one up there and put a bunch of gasket sealer stuff all over the bottom area. Then put the bolts back in. Then took the crank seal and slid it on with the little plastic ring on it. Tapped it a few times and it slid right on as the plastic ring got pushed off.
Done.
*****Only thing my tranny guy said before I tightened all the bolts......not too tight. He told me if you tighten them too much the gasket will leak. He's built a dozen LT1's and and rebuilt many LS1's........so I guess he knows.
.