Rear Main Seal

eso123 · 11-28-2010, 08:41 PM

'98. 4.0L. Manual. 172k miles. Original owner.

Problem: Leaking rear main seal. New silver-dollar-sized oil spot on the garage floor after sitting for ~24 hours.

Two questions:

1. Has anyone tried product like Bar's for "sealing leaks in the rear main seal?"

2. The clutch is original and will need to be reconstructed somewhat soon. How much more work is involved in replacing the rear main seal as part of the clutch job?

The idea is to somehow "seal" the leak until the clutch goes and do both jobs at one time.

Thanks for your comments. This is a great forum.

pcollins · 11-28-2010, 10:26 PM

I've heard a lot of good things about bars, haven't tried it. I would like to give it a shot on my F150. it has a rear main leak and like you i'm waiting for my clutch to go before fixing it. 90% of the time the flywheel should be removed to resurface it and get a new pilot bearing anyways, and the rear main seal is right behind the flywheel, so it really isn't any extra work at all.

**jhammel85** · 11-28-2010, 11:26 PM

^ Yep. The above sums up what I was going to say.

However, I would stay away from Bar's leaks. I know it kinda works from what I've heard but my personal opinion is that the "fixall in a bottle" stuff is crap. It's best to just fix it, you know?

Good luck with it! Sounds like you've had plenty of time behind the wheel of that faithful truck.

ragajungle · 11-28-2010, 11:26 PM

depending on how bad a leak it is you may not want to wait too long. Eventually the seal will wear down and the tiny tension spring moulded into it will start scoring the crankshaft output and any seals you put on after that will premie ware out.

Big Jim M · 11-29-2010, 10:24 AM

99% of rear mail seal leaks are from blowby pressure building inside the engine.. This can, most times, be repaired by SIMPLY installing a new pcv.. The pcv in older engines should be replaced with EVERY oil change!
Clean the vent system...hoses valve and whatever there is.. See what happens.
Big JIm

eso123 · 11-29-2010, 12:42 PM

All good points, especially not delaying the work to avoid scoring the shaft itself and replacing the PCV, which needs to be done anyway. Thank you all.

**TrexMex** · 11-29-2010, 01:46 PM

I have heard that it is a good practice to replace the rear main seal when doing a clutch job since you already removed the flywheel for resurfacing anyways. About bars leak, isn't that something you don't want to put in your engine if you care about it?

sholzy · 11-29-2010, 06:42 PM

Quote:

Originally Posted by Big Jim M

99% of rear mail seal leaks are from blowby pressure building inside the engine.. This can, most times, be repaired by SIMPLY installing a new pcv.. The pcv in older engines should be replaced with EVERY oil change!
Clean the vent system...hoses valve and whatever there is.. See what happens.
Big JIm

+1 on replacing the PCV. I know first hand on the difference it makes.

sholzy · 11-29-2010, 06:53 PM

Quote:

Originally Posted by TrexMex

About bars leak, isn't that something you don't want to put in your engine if you care about it?

I don't think i would want to put something in my engine that is intended to plug holes.

11-28-2010, 08:41 PM	#1
eso123 New Member Join Date: Oct 2010 Posts: 9 Vehicle Year: 1998 Vehicle Make: Ford Vehicle Model: Ranger I use this vehicle for: Commuting, firewood Rep Power: 0	Rear Main Seal '98. 4.0L. Manual. 172k miles. Original owner. Problem: Leaking rear main seal. New silver-dollar-sized oil spot on the garage floor after sitting for ~24 hours. Two questions: 1. Has anyone tried product like Bar's for "sealing leaks in the rear main seal?" 2. The clutch is original and will need to be reconstructed somewhat soon. How much more work is involved in replacing the rear main seal as part of the clutch job? The idea is to somehow "seal" the leak until the clutch goes and do both jobs at one time. Thanks for your comments. This is a great forum.

11-28-2010, 11:26 PM	#4
ragajungle Member Join Date: Jun 2010 Location: Burlington, WI Posts: 347 Vehicle Year: 1989 Vehicle Make: Ford Vehicle Model: Bronco II I use this vehicle for: Wrench, Mud, Rinse, Repeat Rep Power: 10	depending on how bad a leak it is you may not want to wait too long. Eventually the seal will wear down and the tiny tension spring moulded into it will start scoring the crankshaft output and any seals you put on after that will premie ware out. __________________ 99 Ex Sport 4.0L OHV 4WD 102K 89 BII 2.9L 5 Spd 4x4 197K 97 Ex 5.0L AWD 250K 94 Ex Sport 4.0L OHV 287K-sold

11-29-2010, 12:42 PM	#6
eso123 New Member Join Date: Oct 2010 Posts: 9 Vehicle Year: 1998 Vehicle Make: Ford Vehicle Model: Ranger I use this vehicle for: Commuting, firewood Rep Power: 0	Thanks All good points, especially not delaying the work to avoid scoring the shaft itself and replacing the PCV, which needs to be done anyway. Thank you all.

Thread Tools
Show Printable Version Email this Page
Display Modes
Linear Mode Switch to Hybrid Mode Switch to Threaded Mode

11-28-2010, 10:26 PM	#2
pcollins Member Join Date: Mar 2010 Location: Middle of Nowhere, NY Posts: 957 Vehicle Year: 2012 Vehicle Make: GMC Vehicle Model: Sierra 1500 I use this vehicle for: Around the farm, Daily Driver Rep Power: 12	I've heard a lot of good things about bars, haven't tried it. I would like to give it a shot on my F150. it has a rear main leak and like you i'm waiting for my clutch to go before fixing it. 90% of the time the flywheel should be removed to resurface it and get a new pilot bearing anyways, and the rear main seal is right behind the flywheel, so it really isn't any extra work at all.

11-28-2010, 11:26 PM	#3
jhammel85 On here ignoring work Join Date: Dec 2009 Location: South NJ Posts: 3,798 Vehicle Year: 1987 Vehicle Make: Ford Vehicle Model: Ranger I use this vehicle for: Daily Driver / Off Road from time to time Rep Power: 10	^ Yep. The above sums up what I was going to say. However, I would stay away from Bar's leaks. I know it kinda works from what I've heard but my personal opinion is that the "fixall in a bottle" stuff is crap. It's best to just fix it, you know? Good luck with it! Sounds like you've had plenty of time behind the wheel of that faithful truck.

11-29-2010, 10:24 AM	#5
Big Jim M Member Join Date: Apr 2008 Location: Austin Posts: 2,431 Vehicle Year: 2002 Vehicle Make: Ford Vehicle Model: Ranger FX-4 level 2 I use this vehicle for: DD with 31X10.50 Firestone LE's offroad with 31X10.50 MT's Rep Power: 19	99% of rear mail seal leaks are from blowby pressure building inside the engine.. This can, most times, be repaired by SIMPLY installing a new pcv.. The pcv in older engines should be replaced with EVERY oil change! Clean the vent system...hoses valve and whatever there is.. See what happens. Big JIm

11-29-2010, 01:46 PM	#7
TrexMex Premium Member Join Date: Sep 2007 Posts: 406 Vehicle Year: 1994 Vehicle Make: Ford Vehicle Model: Ranger 4X4 Rep Power: 16	I have heard that it is a good practice to replace the rear main seal when doing a clutch job since you already removed the flywheel for resurfacing anyways. About bars leak, isn't that something you don't want to put in your engine if you care about it?