rear main seal info

1941 - 1945, MB, GPW Technical questions and discussions, regarding anything related to the WWII jeep.
Post Reply
gpwmke
G-Brigadier General
G-Brigadier General
Posts: 2010
Joined: Thu Jul 10, 2003 4:13 pm
Location:

Re: rear main seal info

Post by gpwmke » Sat Mar 19, 2016 8:49 am

Hi,
I have read thru this post and admit there is allot of information to mull over. Being a novice at this could you explain to me what indexing is?
The conclusions I have drawn are, the rope seal is the old reliable when installed right, the Payen seal from Europe is by consensus the better/best way to go, the seal system from National was great but no longer available, and John Bizal sells a seal kit similar to what the old National seal was. Am I correct on all this?
I also gleaned there is an email address to contact the Payen seal people. Can someone please post it again.
Best wishes; Leo


User avatar
artificer
banned
Posts: 13558
Joined: Tue Jul 11, 2006 10:46 am
Location: SINGAPORE

Re: rear main seal info

Post by artificer » Sat Mar 19, 2016 11:48 am

Indexing is simply having the rear main seal joins encapsulated inside the rear main bearing cap & the engine block rather than butt joined where the engine block & rear main cap mate.
This is shown in the diagram & the degree amount is not critical!
It could be 45* if this could be easily achieved.
Image
This 'indexing' process is commonly manufacturer recommended with neoprene split type seals.
Saying it can't be done [or asking for proof of others 'indexing'] indicates an extremely low level of 'practical' exposure to the trade.

Currently the most common full circle, non joined seal has become standard for sealing modern cranks so these recommended type practices have become redundant, until we have to repair an older engine.

These split type neoprene seals can be fitted with the crankshaft out or with the crank main bearings loosened enough to push the old rear main oil seal out [no matter what type is being replaced] & then pushing the new neoprene type seal in & offsetting with the lip facing toward the engine oil.
A good offsetting & removal tool to use is a bamboo chop stick.
DO NOT use anything that can possibly slip, scratch or damage the crank journal like, for example, a screw driver.

The older flexible rope seal is more forgiving on a 'rough, lightly pitted, journal' BUT needs to be fitted properly as shown in the earlier video & trimmed level with the engine block. These type seals can't be index fitted.
Leo wrote:National was great but no longer available, and John Bizal sells a seal kit similar to what the old National seal was. Am I correct on all this?
This I can't comment on.
John GIBBINS Member Institute of Automotive Mechanical Engineers [Ret], ASE Master Medium/Heavy Truck & Auto Technician USA -2002 Licensed Motor Mech NSW MVIC 49593 Current 2015
TO DIAGNOSE, TROUBLESHOOT OR FAULT FIND ANY AUTO SYSTEM....
Understand how system parts interact with one another. GOOD parts can then be established & the NOT GOOD problem/s part/s isolated for repair or replacement.

gpwmke
G-Brigadier General
G-Brigadier General
Posts: 2010
Joined: Thu Jul 10, 2003 4:13 pm
Location:

Re: rear main seal info

Post by gpwmke » Sat Mar 19, 2016 2:23 pm

Thanks John for helping a novice understand some of the tricks of the trade. Best wishes; Leo

Chevy427z
G-Sergeant
G-Sergeant
Posts: 48
Joined: Mon Aug 24, 2015 8:37 pm
Location: Clinton, NC, by way of Providence, RI, Moses Lake, Washington, and Wappingers Falls, NY
Contact:

Re: rear main seal info

Post by Chevy427z » Sat Mar 19, 2016 2:27 pm

Leo,

Your summation seems to have captured everything. I don't have the email to contact the Peyen people directly, otherwise I'd share it.


Artificer,

Nice sketch and description!

Mark

Editted: Had to find the guy's email address who sells the Peyen seals in the Netherlands. His name is Joop and his email is "info@staman.nl".
1942 GPW 18219
My Home Machine Shop: http://www.sternbachmachine.com

User avatar
artificer
banned
Posts: 13558
Joined: Tue Jul 11, 2006 10:46 am
Location: SINGAPORE

Re: rear main seal info

Post by artificer » Sat Mar 19, 2016 6:28 pm

It is not my practice to replace rear main seals unless the crank is out & everything is fully cleaned up....BUT....
Removing a packed in old rope type rear main seal from the engine block with loosened mains is possible:

Here is a tool called a Sneaky Pete made specifically for this task. It is available through Amazon & most auto supply houses....
Image

DO NOT FORGET TO LUBE THE OIL SEAL LIP & THE JOURNAL WHEN ASSEMBLING.
John GIBBINS Member Institute of Automotive Mechanical Engineers [Ret], ASE Master Medium/Heavy Truck & Auto Technician USA -2002 Licensed Motor Mech NSW MVIC 49593 Current 2015
TO DIAGNOSE, TROUBLESHOOT OR FAULT FIND ANY AUTO SYSTEM....
Understand how system parts interact with one another. GOOD parts can then be established & the NOT GOOD problem/s part/s isolated for repair or replacement.

User avatar
artificer
banned
Posts: 13558
Joined: Tue Jul 11, 2006 10:46 am
Location: SINGAPORE

Re: rear main seal info

Post by artificer » Sun Mar 20, 2016 1:43 am

DO NOT FORGET TO LUBE THE OIL SEAL LIP & THE JOURNAL WHEN ASSEMBLING.
John GIBBINS Member Institute of Automotive Mechanical Engineers [Ret], ASE Master Medium/Heavy Truck & Auto Technician USA -2002 Licensed Motor Mech NSW MVIC 49593 Current 2015
TO DIAGNOSE, TROUBLESHOOT OR FAULT FIND ANY AUTO SYSTEM....
Understand how system parts interact with one another. GOOD parts can then be established & the NOT GOOD problem/s part/s isolated for repair or replacement.

Joe Gopan
Jeep Heaven
Posts: 49841
Joined: Sun Mar 02, 2008 12:37 pm
Location: Proving Ground

Re: rear main seal info

Post by Joe Gopan » Sun Mar 20, 2016 8:10 am

And apply a dab of "stickum" to the bitt ends of molded seals.
2011 MVPA PIONEER AWARD - MVPA #1064
HONOR GRAD-WHEELED VEHICLE MECHANIC SCHOOL 1960 - US ARMY ORDNANCE SCHOOL(MACHINIST) ABERDEEN PG 1962 - O-1 BIRD DOG CREWCHIEF - 300,000+TROUBLE FREE M-38A1 MILES
LIFE MEMBER AM LEGION-40/8-DAV
7 MIL SPEC MAINTAINED MV'S
COL. BRUNO BROOKS (ARMY MOTORS) IS MY HERO

selfridge
G-Civilian
Posts: 2
Joined: Sun Oct 09, 2016 10:36 am
Location:

Re: rear main seal info

Post by selfridge » Mon Oct 10, 2016 7:34 am

I'm on my third neoprene rear main seal and it is now leaking after 200 miles. The engine only has 1,200 miles on it since re-build. I want to switch to rope and want to know if I can do this without pulling the engine YET AGAIN??!!

Jim

Chriss
G-Staff Sergeant
G-Staff Sergeant
Posts: 57
Joined: Fri Oct 26, 2012 4:58 am
Location:

Re: rear main seal info

Post by Chriss » Mon Oct 10, 2016 8:10 am

Jim,

If you switch to rope you will need to remove the crank to install the new seal. A neoprene seal can be fitted without removing the crank.

The seal itself might not be the cause of the problem. Some questions - What make of neoprene seal are you using? What is the crank like where the seal is running, any pitting? Has this part of the crank been ground undersize, if so to what size?

selfridge
G-Civilian
Posts: 2
Joined: Sun Oct 09, 2016 10:36 am
Location:

Re: rear main seal info

Post by selfridge » Mon Oct 10, 2016 9:56 am

Chris, the seal is a Felpro. The 1st two were Victors. As I recall the crank where the seal rides didn't have any pits (it has been a while since I last had the engine out) I guess I will have to pull it for a 4th time, inspect and mic the seal ride area.

Thanks,

Jim

User avatar
artificer
banned
Posts: 13558
Joined: Tue Jul 11, 2006 10:46 am
Location: SINGAPORE

Re: rear main seal info

Post by artificer » Mon Oct 10, 2016 2:45 pm

I recollect someone mentioning recently Ron Fitzpatrick is now selling the correct section rear main seals. If so why not patronize the owner of this G503 site?

Pictures always help as no one knows which type 'section' Fel pro seal one is talking about.
If the seal looks like this wiper type don't use:
viewtopic.php?f=4&t=219390&start=60#p1557367

The following type section lip seal is what is recommended.
The brand name seems irrelevant, as most are re-packaged anyway.
viewtopic.php?f=4&t=219390&start=60#p1574131
John GIBBINS Member Institute of Automotive Mechanical Engineers [Ret], ASE Master Medium/Heavy Truck & Auto Technician USA -2002 Licensed Motor Mech NSW MVIC 49593 Current 2015
TO DIAGNOSE, TROUBLESHOOT OR FAULT FIND ANY AUTO SYSTEM....
Understand how system parts interact with one another. GOOD parts can then be established & the NOT GOOD problem/s part/s isolated for repair or replacement.

Chriss
G-Staff Sergeant
G-Staff Sergeant
Posts: 57
Joined: Fri Oct 26, 2012 4:58 am
Location:

Re: rear main seal info

Post by Chriss » Tue Oct 11, 2016 6:56 am

The other types of neoprene seal that Jim mentioned are indeed wiper seals and as we know are prone to early failure.

Ron's new seal is a lip seal and that is what I mentioned on here a while back. I have now used it sucessfully so would have no hesitation in recommending it. However as with any seal of this type the running surface needs to have a decent finish without any pitting.

There is no need to pull the engine. Just drain the oil, drop the oil pan and remove the rear main bearing cap. If the running surface is good then using some wooden sticks you should be able to swap over the seal. It is a bit fiddly but I have done it so it is possible........

johnq57
G-Private
G-Private
Posts: 3
Joined: Mon Oct 17, 2016 12:35 am
Location:

Re: rear main seal info

Post by johnq57 » Tue Oct 18, 2016 11:33 pm

Hi, Limey here! I can confirm that both rope and lip seals for the rear engine oil seal are available from http://www.jeeparts.co.uk/Jeeparts/home.php in the UK
Graham and Amanda are very helpful and knowledgeable, so I'd highly recommend them.

User avatar
Eddie Holland
G-Colonel
G-Colonel
Posts: 1582
Joined: Sat Nov 29, 2003 4:22 am
Location: Calvert City Kentucky

Re: rear main seal info

Post by Eddie Holland » Tue Jan 31, 2017 1:10 pm

the seal Sean Collins posted on page 4 of this post would not fit in my
Dec 30 1942 GPW. The picture looks identical to the one I got from Ron F. Same seal same packaging and instructions. I called to complain the rubber side plugs were to big to fit in the caps. They ask me how the actual crank seal fit. I told them the block half was above the block surface about 3/16" on each side and on the cap half the seal was about 1/16" above the surface. they said it should not be more than .040" above the block surface.. Scott at Rons... said do not use that seal in that engine. You have a early non standard block and you need to take it out and have a rop seal fitted.
http://www.cj-2a.com/techtips/engine/re ... al-1xL.jpg
42 GPW 12/30/42 Matching #'s 88,638 being restored
Restoring
M-151 Ford
M-151-A1 Ford
M-151-A2 AMG restored
2 M-416 restored
restoring 2 M-100s

Ironman2
G-Private
G-Private
Posts: 3
Joined: Thu Oct 11, 2018 12:17 pm
Location:

Re: rear main seal info

Post by Ironman2 » Fri Oct 12, 2018 5:43 am

I have installed a Best Gasket brand neoprene single lip seal on my L134 and it has totally stopped piddling on my floor (greater than 800 miles so far). Mine came originally with a rope seal, and I have tried both the double lip omnix seal (dont waist your time or money)and the rope (still piddled a little) and the best gasket just works. I know the neoprene is not what came factory but it sure works... Just be sure to use a good thin coat of Permatex #2 on the outer circumference part of the seal and all mating surfaces of the rear bearing cap and in the drilled holes where the rubber dowl seal goes. Also keep permatex light where it gets near the crank itself. One word of caution, Use good quality shop rags to assemble your engine. I bought some from Harbor Freight and the lint left behind in the engine built up on the oil screen of the pickup and starved the bearings of oil after about a hundred miles... I'm now dealing with the aftermath of that folly (long story not for this thread).... Remember cleanliness is next to Godliness in Holy Toledo engine land....


Post Reply

Return to “MB GPW Technical Knowledge Base”

Who is online

Users browsing this forum: No registered users and 43 guests