Rear engine seal

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Auzziemutt
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Rear engine seal

Unread post by Auzziemutt » August 6th, 2018, 11:58 pm

After three years of putting it off I have taken the powertrain out of my A2. The gearbox expert said that's mainly stuffed so a nos one is on it's way from Red River along with a dozen other parts I'll need .The clutch disc was dripping oil so a seal is gone , the nos box will have a good front seal so I want to replace the rear engine seal. my question is, it looks like any other seal that can levered out and replaced but do I have to do anything to the crankshaft , like unbolt it or something else. The last rear seal I replaced was done decades ago and was the two piece rope type that cant be replaced easily. I need a little expert advice please.

Grasshopper
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Re: Rear engine seal

Unread post by Grasshopper » August 7th, 2018, 6:10 am

My rear main leaked, and it popped out easily by pushing against the top of the seal (which made the bottom pop out). I installed a new item and that turned out to leak too! I suspect mine actually leaks around the outside of the seal, as the new one felt pretty loose going in. I'll use an appropriate fixing/sealing compound next time (my power pack is all coming out again this winter for some transmission and engine work).

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rickf
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Re: Rear engine seal

Unread post by rickf » August 7th, 2018, 8:39 am

I usually drill a small and shallow hole in each side of the main seal and thread in a screw in each hole a couple threads and then use a pair of side cutters to pry the seal out. This way you are not chancing scoring the crank or block surface. When installing the new seal put a sealer like Permatex #2 or #3 on the outside of the seal and very carefully tap it into position making sure it goes in straight. This is where the leaks come from is if it does not go in straight and the seal deforms so take your time and tap around it gently and slowly work it in. The sealer will also act as a lubricant to help it go in but wear gloves because it will get on you and it is a bear to get off. Carb cleaner gets it off but it drys out your skin. Do NOT get the sealer on the inner part of the seal!
1964 M151A1
1984 M1008
1967 M416
04/1952 M100
12/1952 M100- Departed
AN/TSQ-114A Trailblazer- Gone

kmam
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Re: Rear engine seal

Unread post by kmam » August 7th, 2018, 10:06 am

This is from my mate who worked on my engine which may help...

The seal is a (one piece) seal that fits into the engine block and the rear main bearing cap. It is fitted after the rear main bearing cap has been fitted. The cap also has four side seals (two on each side) that seal the rear of the engine also.
He has to determine what is the cause of the seal leaking.
It could be.
1 Main bearings are shot, he should lift the rear main bearing and take a look at the bearing and do a bearing clearance check. How was the oil pressure?
2 It could be that the rear of the crankshaft is worn in the area of the seal and would need a speedy sleeve or machining and fitment of a sleeve.
No good changing the seal if not determining the cause of the leaking.
Howard

Daimler Ferret Mk 1/2
AM General M151A2
Austin Champ

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rickf
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Re: Rear engine seal

Unread post by rickf » August 7th, 2018, 10:18 am

This is all true Howard but in his case it appears that the oil was coming from the transmission and he is replacing the rear main because he is there and it is accessible. Crankshafts are hardened so you seldom see a groove in them although I have seen it in very high mileage engines. The problem with checking the rear main bearing is do you check just the rear main or, should I check all the mains? Well I am here so I guess I will check the rods while I am at it. " The motor is out, It is easy to get the head off, I wonder if I should check the rings? Next thing you know the engine is torn down on the floor for what started out as a rear main seal replacement. :roll: :roll: :roll: :roll:
1964 M151A1
1984 M1008
1967 M416
04/1952 M100
12/1952 M100- Departed
AN/TSQ-114A Trailblazer- Gone

Auzziemutt
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Re: Rear engine seal

Unread post by Auzziemutt » August 9th, 2018, 3:23 am

Thanks Grasshopper I was hoping it was that simple. And thanks Kmam but Im trying to keep the job as simple as possible . Gearbox, full clutch, water pump, thermostat and a few seals will keep it going well. Rick, your idea was exactly what I thought up while waiting for a reply but I didn't like to mention it ,it sounds like a backyard mechanic job, like I often do, so I'm glad someone else works that way. If it works -----do it. Thanks all.

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svramselaar
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Re: Rear engine seal

Unread post by svramselaar » August 9th, 2018, 4:22 am

hi

dont forget to take a litle grease inside the seal where it sits on the axle :D

george

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rickf
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Re: Rear engine seal

Unread post by rickf » August 9th, 2018, 9:29 am

Auzziemutt wrote:Thanks Grasshopper I was hoping it was that simple. And thanks Kmam but Im trying to keep the job as simple as possible . Gearbox, full clutch, water pump, thermostat and a few seals will keep it going well. Rick, your idea was exactly what I thought up while waiting for a reply but I didn't like to mention it ,it sounds like a backyard mechanic job, like I often do, so I'm glad someone else works that way. If it works -----do it. Thanks all.
The pros use the backyard ways a lot of the time if it is faster and effective. The fastest way to remove the seal is a seal puller which is a sharp edged tool that hooks the seal and levers it out. You can have the seal out in seconds. The downside is that if you are not careful you can also gouge the side of the housing and then you have a leak on the outside of the seal. I have the puller, I use the screws. Sometimes fast is not always fast if you know what I mean.
Here is the puller.

https://www.amazon.com/Lisle-56750-Seal ... BPSEXQJ2BR
1964 M151A1
1984 M1008
1967 M416
04/1952 M100
12/1952 M100- Departed
AN/TSQ-114A Trailblazer- Gone

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