replacing rear main oil seal universal 5424

[argofred]

Dear Sailnet: Anyone know whether the rear main oil seal on my Universal diesel is replaced by dropping the pan and crank or from the rear of the engine? After chugging along for 27 years without a drop in the pan it has stated to leak. Only a couple of teaspoons after 15 hours of use but I anticipate it may get worse in the future. Thanks! Fred

[Maine Sail]

What makes you assume it's the rear main seal? Is it dripping from the weep hole in the bell housing? It could just be an oil pan leak.

The rear main on most all engines is removed off the output end of the crank with the flywheel, & sometimes bell housing, removed. If you do this be very careful to NOT scratch or mar the crank shaft in any way where it meets the rear mains bearing seal surface..

General Instructions:

Remove gear box:

Remove damper plate (you should use an impact driver and a mini butane torch for heat as many damper plate bolts are put in with red Loctite):


Remove flywheel; many times easier said than done due to moisture and the resulting rust. Use a brass or lead hammer if you need to whack it. Never use a metal harder or as hard as the flywheel.


Remove Flywheel; If the flywheel still won't slide off you can make a jig and use the damper plate as a puller. You'll want to replace the damper plate anyway while your in there.



Pulling Jig In Place:


Rear Main Seal; This one was only replaced because I was already "in there". Even at 3000 hours it was not leaking. The oil in and around that area was from a minor valve cover gasket leak.


New Seal:


While not a tough job in terms of difficulty level it can be tedious and time consuming..

[argofred]

Thanks Maine sail! Just what I needed to know with pictures. Will check pan vs weep hole as the source of the leak. It would be nice if the source is the pan as I just (last year) rebuilt the tranny with new damper plate and dripless shaft seal. Best, Fred

[Pub911]

Thanks from ALL OF US Universal owners. I've been 1/2 way there or more, but this really helps if the need arises to press past the flywheel.

Cheers!

[St Anna]

Had the same thing on a Nanni 50Hp (marinised Kubota). Had to remove gear box and back part of the engine to replace a $15 rubber seal.

Exactly the same as MaineSail said. Quite stressful but more confident with engine stuff when finished.

[recycle]

How did you support the engine when removing the bell housing? Did you support it from the oil pan and was that strong enough?

[St Anna]

I put an eye bolt through the cockpit floor to a stainless plate to spread the load, and used a chain pulley to maintain the engine at the same level.

The gear box came off with a crunch but no problems.