Rear Main Seal And Sleeve
Moderators: rickf, raymond, Mr. Recovery
- Mr. Recovery
- Brigadier General
- Posts: 2895
- Joined: December 5th, 2007, 9:03 pm
- Location: New Port Richey, Fl.
- Contact:
Re: Rear Main Seal And Sleeve
I agree with rickf, the only oil plug in that area of the motor is the camshaft rear bearing expansion plug, the one on the lower right in the photo.
1960 M151 Run 1
1963 M151 Willys DoD 10-63 in Baltimore
1989 Alley Cat. "work in Progress"
NRA Life Member
American Legion Post 275 Fl
US Army 6 years 2nd Armored Cavalry Bindlach Germany
Colorado Army Nat. Guard 5 years
Md Air Guard 15 years active duty on C-130's
1963 M151 Willys DoD 10-63 in Baltimore
1989 Alley Cat. "work in Progress"
NRA Life Member
American Legion Post 275 Fl
US Army 6 years 2nd Armored Cavalry Bindlach Germany
Colorado Army Nat. Guard 5 years
Md Air Guard 15 years active duty on C-130's
Re: Rear Main Seal And Sleeve
FLMV.NET has sleeve and TNJMURRY has the correct seal.
M813A1
M35A2
M151A1
M101A2
S169 Shelter
M Tow bar
Big box of Legos
M35A2
M151A1
M101A2
S169 Shelter
M Tow bar
Big box of Legos
-
- Sergeant
- Posts: 54
- Joined: October 13th, 2016, 9:58 am
Re: Rear Main Seal And Sleeve
Is it possible to change the rear main seal without removing the crankshaft? I pulled the pack so I can change the transmission seals , and found the rear main leaks badly when the motor is tilted. I should add that the issue is likely due to lack of use and age of seal.
Thanks in advance
Thanks in advance
- svramselaar
- Major
- Posts: 1109
- Joined: December 30th, 2007, 6:48 am
- Location: holland
Re: Rear Main Seal And Sleeve
hi
normally there is no pressure at the seal
there is a hole at the block so the oil from the bearing can go to the sump
is this hole maybe clocked ??
the seal must sit with the spring to the block and straight
george
normally there is no pressure at the seal
there is a hole at the block so the oil from the bearing can go to the sump
is this hole maybe clocked ??
the seal must sit with the spring to the block and straight
george
Rear Main Seal And Sleeve
Yes, it can be replaced without issues with everything else in place. Insert a few self tapping screws to have something to pull it out with.
Horst
1972 USMC M151A2 w/ROPS (ex Barstow) and M416
1962 M201 and trailer
1966 GTO,1982 E350 Skoolie, 1987 SJ413, 1987 911
Gone: 2xM35A2c, Unimog 404S, Hanomag AL28, DKW Munga
1972 USMC M151A2 w/ROPS (ex Barstow) and M416
1962 M201 and trailer
1966 GTO,1982 E350 Skoolie, 1987 SJ413, 1987 911
Gone: 2xM35A2c, Unimog 404S, Hanomag AL28, DKW Munga
-
- Sergeant
- Posts: 54
- Joined: October 13th, 2016, 9:58 am
Re: Rear Main Seal And Sleeve
Thanks for the good advice. It leaks with the engine out and tilted on the hoist. Didn't take much of a tilt, so anytime it goes up a hill it would be leaking.
Re: Rear Main Seal And Sleeve
I'm just gonna jump in here for a minute and say something I think is important...because in my experience, anytime there is a total rebuild involved, particularly when you've paid someone else to perform the rebuild, catastrophic problems such as you are discussing are most likely the fault of the rebuilder.
So if you've paid a reputable party to perform a rebuild on your engine, STOP what you are doing and contact the rebuilder and have them make good on it. You paid for a rebuilt engine. What you got is a high speed oil distribution system.
Cheers,
TJ
So if you've paid a reputable party to perform a rebuild on your engine, STOP what you are doing and contact the rebuilder and have them make good on it. You paid for a rebuilt engine. What you got is a high speed oil distribution system.
Cheers,
TJ
-
- Sergeant
- Posts: 54
- Joined: October 13th, 2016, 9:58 am
Re: Rear Main Seal And Sleeve
I've known the truck a long time, as I assisted with some of the restoration. The bottom end of the motor wasn't touched (the then owner was at the time an impoverished student) but the head did come off for a check of the bores and installation of hardened valve inserts. He purchased it as a non-runner, but it didn't take much for us to get her running.
The history of the truck is unknown, except for being released from a USAF base here in the UK and the discovery of some Arabic or Hebrew markings on it. I'm under no illusion that one day I might need to rebuild the motor, but for now she doesn't smoke, has good oil pressure and runs at a good temperature so I'll leave alone. Given that the oil seals in the transmission, which was purchased from a dealer at a show as NOS overhauled have gone hard and leaked (likely due to poor quality seals or age hardening), I suspect that the rear crank seal has suffered similarly, or has an issue from days in service. If there is any suspicion of bottom end issues, I will investigate and attend to them.
The history of the truck is unknown, except for being released from a USAF base here in the UK and the discovery of some Arabic or Hebrew markings on it. I'm under no illusion that one day I might need to rebuild the motor, but for now she doesn't smoke, has good oil pressure and runs at a good temperature so I'll leave alone. Given that the oil seals in the transmission, which was purchased from a dealer at a show as NOS overhauled have gone hard and leaked (likely due to poor quality seals or age hardening), I suspect that the rear crank seal has suffered similarly, or has an issue from days in service. If there is any suspicion of bottom end issues, I will investigate and attend to them.
Re: Rear Main Seal And Sleeve
In order to tilt the engine far enough for the oil level to reach that main seal you would have to be on a hill it is unlikely you would be able to climb. I have seen a lot of leaky rear main seals and even one that someone forgot to put in but not as bad as what you are describing, not even the missing seal. It was just a steady drip. Albeit a fast drip. Crankshafts are hardened steel so unless there was a steady supply of sand in there, unlikely due to the closed area, then there is probably no groove and just a dried out seal. Unless you have money to burn I would just get the seal first and then if you need a sleeve get that, it would only be a couple day wait.
1964 M151A1
1984 M1008
1967 M416
04/1952 M100
12/1952 M100- Departed
AN/TSQ-114A Trailblazer- Gone
1984 M1008
1967 M416
04/1952 M100
12/1952 M100- Departed
AN/TSQ-114A Trailblazer- Gone
-
- Sergeant
- Posts: 54
- Joined: October 13th, 2016, 9:58 am
Re: Rear Main Seal And Sleeve
Having stripped the clutch and flywheel off, I didn't realise that the holes in the crank for the flywheel bolts went straight through. The flywheel bolts didn't seem particularly tight either, so this may have been the cause of my leak. The flywheel bolt holes also seem slightly oval, but I've no time to do anything about that for now but should further issues manifest, I'll either have have the flywheel machined back to spec or install a new one. The flywheel didn't seem to move and located positively when installed; what did surprise me is the lack of a drive dowel on the crank/flywheel interface but I guess being an industrial motor this wasn't considered necessary. Most motors I've worked on have them. The old oil crank seal looked ok, but seemed to be installed slightly askew. I renewed it, dressed the crank shaft and flywheel mating faces, re-assembled it all and tipped the engine up and it now no longer leaks so I'm happy. To be fair it only seemed to leak out when I tilted the motor to about 30 degrees, which its unlikely to do with normal driving but I don't like the idea of oil leaks as they normally indicate a problem.
Having renewed the transmission seals, the pack now just needs re-assembling and installing. The output seal for the rear drive shaft on the transmission turned out to be covered with "silicone snot" on the inside and outside, so I am now suspicious of this transmission (which was purchased from a dealer by a previous owner as NOS army reconditioned). It seems to drive ok, doesn't jump gears and has no excessive play so I'll just have to see how it goes. I swapped out the sliding flanges from my spare transmission and they have far less play on the splines than the ones that were installed, so hopefully this cures the rather worrying oil loss from this area.
Somebody pointed out in a picture of my MUTT on another thread that my temperature gauge was the incorrect one, and as it doesn't seem to work I've taken the opportunity to fit a new sender and obtain (hopefully!) the correct gauge too. My intention is to be on the road for a local event in 2 weeks.
Having renewed the transmission seals, the pack now just needs re-assembling and installing. The output seal for the rear drive shaft on the transmission turned out to be covered with "silicone snot" on the inside and outside, so I am now suspicious of this transmission (which was purchased from a dealer by a previous owner as NOS army reconditioned). It seems to drive ok, doesn't jump gears and has no excessive play so I'll just have to see how it goes. I swapped out the sliding flanges from my spare transmission and they have far less play on the splines than the ones that were installed, so hopefully this cures the rather worrying oil loss from this area.
Somebody pointed out in a picture of my MUTT on another thread that my temperature gauge was the incorrect one, and as it doesn't seem to work I've taken the opportunity to fit a new sender and obtain (hopefully!) the correct gauge too. My intention is to be on the road for a local event in 2 weeks.