Rear main seal

exnoodle · 06-20-2019, 08:40 PM

Recently purchased an M3, 6 speed MT with 113K.

Replaced rod bearings, oil pan gasket, motor mounts, MT fluid, belts (now on the right way, thank you guys), spark plugs, valve cover gasket, vapor canister valve, K&N air filter, and repainted the valve covers.

Next I am going to the drive shaft and replace the GUIBO, bearing and trans mounts. Car shakes at 1200-2000 RPM only in 1st and 2nd, think this is the culprit.

Question: I have oil coming out between the transmission and rear of the engine. Thinking it could be the rear main seal. Any thoughts & is there a DIY? Clutch feels good and smooth, I assume it has some life on it.

Kisenwether · 06-20-2019, 08:55 PM

Quote:

Originally Posted by exnoodle

Recently purchased an M3, 6 speed MT with 113K.

Replaced rod bearings, oil pan gasket, motor mounts, MT fluid, belts (now on the right way, thank you guys), spark plugs, valve cover gasket, vapor canister valve, K&N air filter, and repainted the valve covers.

Next I am going to the drive shaft and replace the GUIBO, bearing and trans mounts. Car shakes at 1200-2000 RPM only in 1st and 2nd, think this is the culprit.

Question: I have oil coming out between the transmission and rear of the engine. Thinking it could be the rear main seal. Any thoughts & is there a DIY? Clutch feels good and smooth, I assume it has some life on it.

If you just had rod bearings done that is most likely left over oil that pooled in the transmission area and is slowly coming back out now.

SAMM3Y · 06-20-2019, 08:59 PM

Quote:

Originally Posted by Kisenwether

Quote:

Originally Posted by exnoodle

Recently purchased an M3, 6 speed MT with 113K.

Replaced rod bearings, oil pan gasket, motor mounts, MT fluid, belts (now on the right way, thank you guys), spark plugs, valve cover gasket, vapor canister valve, K&N air filter, and repainted the valve covers.

Next I am going to the drive shaft and replace the GUIBO, bearing and trans mounts. Car shakes at 1200-2000 RPM only in 1st and 2nd, think this is the culprit.

Question: I have oil coming out between the transmission and rear of the engine. Thinking it could be the rear main seal. Any thoughts & is there a DIY? Clutch feels good and smooth, I assume it has some life on it.

If you just had rod bearings done that is most likely left over oil that pooled in the transmission area and is slowly coming back out now.

Bingo.. when you removed the sump rogue oil spills into the trans bell housing and if you don't soak it up with sump off it'll slowly make its way out

amrazM · 06-20-2019, 09:37 PM

If it’s a considerable amount of oil leaking drop the gearbox and do the RMS.

It’s a considerable amount of work to do the guibo as the exhaust and heat shields have to come out. Just drop the gearbox and change the RMS at the same time it’s not that hard.

amrazM · 06-20-2019, 09:43 PM

Diy,

Raise car securely. Drop exhaust. Remove heatshields from the diff foward. Remove driveshaft and keep it from over extending. Remove lower 6 transmission to engine bolts. Support gearbox. Drop transmission. crossmember. Lower trans. Remove upper bolts. Then separate trans from motor.

You need a special tool to remove the seal and press it back in without damaging the bore.

pbonsalb · 06-21-2019, 06:32 AM

I would wait until after the car has been driven a few weeks to make sure the seal is leaking rather than residual oil from the bearing change. If the seal is not leaking, leave it and do it with the clutch in a few years.

exnoodle · 06-22-2019, 04:14 PM

I was pretty meticulous about cleaning off all the excess oil on and around the engine, but can't be perfect. I will clean it up, wait and see. Guibo wont be here for another couple of days, so I can buy some time.

AmrazM, what is the special tool needed to pull and place the seal?

exnoodle · 07-01-2019, 08:03 PM

Its still leaking and the amount of engine oil is reducing. I think my bad rear rod bearing may have cause accelerated wear of this seal maybe.

Ordering the seal and clutch alignment tool, and make it happen. Will update w/ pics.

Read up on the procedure, will try and make the 'special tool' to slide the seal onto the shaft uniformly, with steel pipe, some plate, threaded rod, nut/washer and my mig welder. Will post pics if I am successful in making this tool.

8500RPM · 07-01-2019, 08:06 PM

1st I've heard of a leaking main seal on this platform. Maybe your oil pan didn't seal correctly?

amrazM · 07-01-2019, 10:00 PM

Quote:

Originally Posted by 8500RPM

1st I've heard of a leaking main seal on this platform. Maybe your oil pan didn't seal correctly?

RMS leak, every Bmw gasket leaks. It’s not a surprise.

pbonsalb · 07-02-2019, 05:21 AM

Eventually. The point is that we have not read much about it happening yet on E9xM3, which are 6-11 years old, even with higher mileage examples. The OP’s car has only 113k miles. I agree that if it needs a rear main seal, it is an outlier.

I also do not think worn rod bearings would cause a rear main seal to leak. Many have had worn rod bearings but none seem to have had rear main seal leaks.

Yes, it will leak eventually. When I change my clutch I will do mine, unless it actually does leak significantly before then.

exnoodle · 07-02-2019, 07:34 PM

I just assumed with the higher particulate count in the oil, it may wear that seal more. My rear rod bearing, closest to the RMS were the worst, with chunks of copper missing.

Will keep you guys posted on what I learn.

XKxRome0ox · 07-02-2019, 09:44 PM

Quote:

Originally Posted by amrazM

Diy,

Raise car securely. Drop exhaust. Remove heatshields from the diff foward. Remove driveshaft and keep it from over extending. Remove lower 6 transmission to engine bolts. Support gearbox. Drop transmission. crossmember. Lower trans. Remove upper bolts. Then separate trans from motor.

You need a special tool to remove the seal and press it back in without damaging the bore.

is that all it takes?
sounds like a piece of cake

-_-

pbonsalb · 07-02-2019, 09:55 PM

Also a clutch and flywheel to pull.

exnoodle · 07-03-2019, 08:18 PM

and would need a clutch alignment tool, I assume. Along with whatever to put on the seal. Ordered the parts, let me know if you guys think I should get anything else.

deansbimmer · 07-04-2019, 11:24 AM

The rear seal is a very large diameter, like 6". The correct seal press is prohibitively expensive and you won't find it for rent. The seal is relatively fragile and very difficult to seat straight without damaging it if you attempt to do it redneck style with hammers, wood blocks etc. If you attempt it DIY anyway, I'd have at least two seals on hand in the likely case you damage one.

exnoodle · 07-05-2019, 01:33 PM

Deansbimmer - I agree with you, installing a seal is very delicate. I was not planning on using a hammer or wood blocks.

I was thinking of building the seal press. Was going to get a steel pipe (of the right OD), welding a plate to one end, drilling a hole through the plate, and placing a threaded rod with a nut in the middle. Use that to uniformly slide the seal into place.

Does the seal go on dry or can it be lightly lubricated w/ engine oil or redline assembly fluid? Should I heat up the OD of the engine bock (with a heat gun) to help expand the metal slightly to better accept the new seal?

pbonsalb · 07-05-2019, 01:48 PM

I assume you have looked at this:

https://workshop-manuals.com/bmw/3_s...ft_seal_(s65)/

deansbimmer · 07-05-2019, 02:23 PM

Quote:

Originally Posted by exnoodle

I was thinking of building the seal press. Was going to get a steel pipe (of the right OD), welding a plate to one end, drilling a hole through the plate, and placing a threaded rod with a nut in the middle. Use that to uniformly slide the seal into place.

Does the seal go on dry or can it be lightly lubricated w/ engine oil or redline assembly fluid? Should I heat up the OD of the engine bock (with a heat gun) to help expand the metal slightly to better accept the new seal?

Problems to overcome with a DIY tool:
-The crankshaft snout is flush with the block so you need a mandrel the exact diameter of the crankhaft to allow the seal wiper to slide past the edge of the crank without tearing it.

-There is no threaded bore on the crankshaft center to permit threading in a center bolt and "pulling" the seal on.

-The seal is about 5" in diameter, sourcing a steel pipe the right diameter will be difficult. You really need a lathe to fab a tool equivalent to the BMW version.

-Additionally, the force required to pull in the seal to the block is significant. You'll probably pull the threads out of anything home made trying to get it in.

No, You cannot heat the block up to enlarge it, and you definitely must install the seal dry unless you want to do the job again later on. You also need to use sealant at the block split.

Read the TIS instruction pbonsalb posted. It will help see what you're up against.
No offense intended but this is normally what I'd consider best left to a professional with the right tools and experience. It's not a fun job to have to do twice. Best of luck whichever way you decide!

exnoodle · 07-05-2019, 04:38 PM

I have read up on the stories and have experience replacing similar seals. 100% agree with having the right tool. I have read the workshop manual, appreciate the link.

I am still thinking through the details, but thoughts so far, at a high level, recreate the tool in the manual. Get seal in the mail, hopefully coming soon, go to Metal Supermarket. They will cut and machine steel to my specs and at any size. I will pick up the nuts, bolts and threaded screws. Thinking the tool will run me around $100, depending on how close I can get stock steel to the right OD's. Will post pics on my progress.

pbonsalb · 07-05-2019, 07:17 PM

Post the details for the rest of us DIYers who might do it one day.

exnoodle · 07-13-2019, 03:39 PM

My Elring rear main seal just arrived. My backup ride (2004 E46 ZHP) has a flat tire, so down to 1 car. New tire is coming in & once it is on, I will put the M3 on the lift and take my time. Hate being rushed and the DIY becomes less enjoyable. I also want to create a DIY for the folk on this forum.

I found this post, thinking I can replicate a similar tool out of PVC, threaded rod, a plate, washers and bolts.
http://forums.pelicanparts.com/porsc...tion-tool.html

The intent is to uniformly press the seal in, think this may do it, although a little slow with the speed in which you can turn down the 3 bolts, but might just work.

And yes, it is a big seal, just shy of 5 inches OD.

Will keep you posted.

06-20-2019, 08:40 PM	#1
exnoodle Private 25 Rep 60 Posts Drives: BMW M3 (E93) Join Date: Jun 2019 Location: NY iTrader: (0)	Rear main seal Recently purchased an M3, 6 speed MT with 113K. Replaced rod bearings, oil pan gasket, motor mounts, MT fluid, belts (now on the right way, thank you guys), spark plugs, valve cover gasket, vapor canister valve, K&N air filter, and repainted the valve covers. Next I am going to the drive shaft and replace the GUIBO, bearing and trans mounts. Car shakes at 1200-2000 RPM only in 1st and 2nd, think this is the culprit. Question: I have oil coming out between the transmission and rear of the engine. Thinking it could be the rear main seal. Any thoughts & is there a DIY? Clutch feels good and smooth, I assume it has some life on it.
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06-20-2019, 09:37 PM	#4
amrazM mTekMods 2142 Rep 2,901 Posts Drives: like a granny. Join Date: Jan 2010 Location: Manhatan iTrader: (1)	If it’s a considerable amount of oil leaking drop the gearbox and do the RMS. It’s a considerable amount of work to do the guibo as the exhaust and heat shields have to come out. Just drop the gearbox and change the RMS at the same time it’s not that hard.
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06-20-2019, 09:43 PM	#5
amrazM mTekMods 2142 Rep 2,901 Posts Drives: like a granny. Join Date: Jan 2010 Location: Manhatan iTrader: (1)	Diy, Raise car securely. Drop exhaust. Remove heatshields from the diff foward. Remove driveshaft and keep it from over extending. Remove lower 6 transmission to engine bolts. Support gearbox. Drop transmission. crossmember. Lower trans. Remove upper bolts. Then separate trans from motor. You need a special tool to remove the seal and press it back in without damaging the bore.
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06-21-2019, 06:32 AM	#6
pbonsalb Lieutenant General 5234 Rep 10,614 Posts Drives: 18 F90 M5, 99 E36 M3 Turbo Join Date: Feb 2011 Location: New England iTrader: (4)	I would wait until after the car has been driven a few weeks to make sure the seal is leaking rather than residual oil from the bearing change. If the seal is not leaking, leave it and do it with the clutch in a few years.
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06-22-2019, 04:14 PM	#7
exnoodle Private 25 Rep 60 Posts Drives: BMW M3 (E93) Join Date: Jun 2019 Location: NY iTrader: (0)	I was pretty meticulous about cleaning off all the excess oil on and around the engine, but can't be perfect. I will clean it up, wait and see. Guibo wont be here for another couple of days, so I can buy some time. AmrazM, what is the special tool needed to pull and place the seal?
	Appreciate 0 Quote

07-01-2019, 08:03 PM	#8
exnoodle Private 25 Rep 60 Posts Drives: BMW M3 (E93) Join Date: Jun 2019 Location: NY iTrader: (0)	Its still leaking and the amount of engine oil is reducing. I think my bad rear rod bearing may have cause accelerated wear of this seal maybe. Ordering the seal and clutch alignment tool, and make it happen. Will update w/ pics. Read up on the procedure, will try and make the 'special tool' to slide the seal onto the shaft uniformly, with steel pipe, some plate, threaded rod, nut/washer and my mig welder. Will post pics if I am successful in making this tool.
	Appreciate 0 Quote

07-01-2019, 08:06 PM	#9
8500RPM First Lieutenant 152 Rep 303 Posts Drives: 2012 M3 CP Join Date: Dec 2017 Location: Ft. Lauderdale, FL iTrader: (0)	1st I've heard of a leaking main seal on this platform. Maybe your oil pan didn't seal correctly?
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07-02-2019, 05:21 AM	#11
pbonsalb Lieutenant General 5234 Rep 10,614 Posts Drives: 18 F90 M5, 99 E36 M3 Turbo Join Date: Feb 2011 Location: New England iTrader: (4)	Eventually. The point is that we have not read much about it happening yet on E9xM3, which are 6-11 years old, even with higher mileage examples. The OP’s car has only 113k miles. I agree that if it needs a rear main seal, it is an outlier. I also do not think worn rod bearings would cause a rear main seal to leak. Many have had worn rod bearings but none seem to have had rear main seal leaks. Yes, it will leak eventually. When I change my clutch I will do mine, unless it actually does leak significantly before then.
	Appreciate 0 Quote

07-02-2019, 07:34 PM	#12
exnoodle Private 25 Rep 60 Posts Drives: BMW M3 (E93) Join Date: Jun 2019 Location: NY iTrader: (0)	I just assumed with the higher particulate count in the oil, it may wear that seal more. My rear rod bearing, closest to the RMS were the worst, with chunks of copper missing. Will keep you guys posted on what I learn.
	Appreciate 0 Quote

07-02-2019, 09:55 PM	#14
pbonsalb Lieutenant General 5234 Rep 10,614 Posts Drives: 18 F90 M5, 99 E36 M3 Turbo Join Date: Feb 2011 Location: New England iTrader: (4)	Also a clutch and flywheel to pull.
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07-03-2019, 08:18 PM	#15
exnoodle Private 25 Rep 60 Posts Drives: BMW M3 (E93) Join Date: Jun 2019 Location: NY iTrader: (0)	and would need a clutch alignment tool, I assume. Along with whatever to put on the seal. Ordered the parts, let me know if you guys think I should get anything else.
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07-04-2019, 11:24 AM	#16
deansbimmer BimmerPost Supporting Vendor 3749 Rep 2,907 Posts Drives: 2011 E93 M3 Join Date: Nov 2014 Location: DFW, Texas iTrader: (17) Garage List 1988 BMW M3 [0.00] 2013 BMW M3 [0.00] 2011 X5M [0.00] 2011 BMW M3 [0.00]	The rear seal is a very large diameter, like 6". The correct seal press is prohibitively expensive and you won't find it for rent. The seal is relatively fragile and very difficult to seat straight without damaging it if you attempt to do it redneck style with hammers, wood blocks etc. If you attempt it DIY anyway, I'd have at least two seals on hand in the likely case you damage one.
	Appreciate 1 exnoodle25.00 Quote

07-05-2019, 01:33 PM	#17
exnoodle Private 25 Rep 60 Posts Drives: BMW M3 (E93) Join Date: Jun 2019 Location: NY iTrader: (0)	Deansbimmer - I agree with you, installing a seal is very delicate. I was not planning on using a hammer or wood blocks. I was thinking of building the seal press. Was going to get a steel pipe (of the right OD), welding a plate to one end, drilling a hole through the plate, and placing a threaded rod with a nut in the middle. Use that to uniformly slide the seal into place. Does the seal go on dry or can it be lightly lubricated w/ engine oil or redline assembly fluid? Should I heat up the OD of the engine bock (with a heat gun) to help expand the metal slightly to better accept the new seal?
	Appreciate 0 Quote

07-05-2019, 01:48 PM	#18
pbonsalb Lieutenant General 5234 Rep 10,614 Posts Drives: 18 F90 M5, 99 E36 M3 Turbo Join Date: Feb 2011 Location: New England iTrader: (4)	I assume you have looked at this: https://workshop-manuals.com/bmw/3_s...ft_seal_(s65)/
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07-05-2019, 04:38 PM	#20
exnoodle Private 25 Rep 60 Posts Drives: BMW M3 (E93) Join Date: Jun 2019 Location: NY iTrader: (0)	I have read up on the stories and have experience replacing similar seals. 100% agree with having the right tool. I have read the workshop manual, appreciate the link. I am still thinking through the details, but thoughts so far, at a high level, recreate the tool in the manual. Get seal in the mail, hopefully coming soon, go to Metal Supermarket. They will cut and machine steel to my specs and at any size. I will pick up the nuts, bolts and threaded screws. Thinking the tool will run me around $100, depending on how close I can get stock steel to the right OD's. Will post pics on my progress.
	Appreciate 0 Quote

07-05-2019, 07:17 PM	#21
pbonsalb Lieutenant General 5234 Rep 10,614 Posts Drives: 18 F90 M5, 99 E36 M3 Turbo Join Date: Feb 2011 Location: New England iTrader: (4)	Post the details for the rest of us DIYers who might do it one day.
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07-13-2019, 03:39 PM	#22
exnoodle Private 25 Rep 60 Posts Drives: BMW M3 (E93) Join Date: Jun 2019 Location: NY iTrader: (0)	My Elring rear main seal just arrived. My backup ride (2004 E46 ZHP) has a flat tire, so down to 1 car. New tire is coming in & once it is on, I will put the M3 on the lift and take my time. Hate being rushed and the DIY becomes less enjoyable. I also want to create a DIY for the folk on this forum. I found this post, thinking I can replicate a similar tool out of PVC, threaded rod, a plate, washers and bolts. http://forums.pelicanparts.com/porsc...tion-tool.html The intent is to uniformly press the seal in, think this may do it, although a little slow with the speed in which you can turn down the 3 bolts, but might just work. And yes, it is a big seal, just shy of 5 inches OD. Will keep you posted.
	Appreciate 0 Quote