RTV900 Crankshaft Seal FYI

v10rick

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Had enough of the oil spots on a clean garage floor. The Kubota service manual does not mention this service...you would think its similar to a car...No? WRONG

I experienced the same frustration, mentioned by another forum member, what a royal PITA.

There is no room to use a seal puller and no room to tap a new seal in place, with a hammer and deep socket.

Ruined one seal because it did not seat evenly, no way to remove without damaging it.

Using the crank bolt and a large fender washer over a short length of PVC pipe (the same diameter as the seal) I was able to seat it successfully.

Since the crank pulley is not keyed several attempts were need to get the crank and pulley alignment marks to match up.

Fortunately I was working under a garage lift, but it took way too much time and effort to make this happen.

A catch tray under the RTV would be a nuisance but a necessary one if the seal leaks in the future.
 

aurthuritis

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first place to check when a crank seal leak is the crankcase vent. positive pressure will push out oil
 

bordercollie

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Those dirt dabbers are notorious for plugging up hoses and anything with an opening. Even just mud can hit just right and do it but the dirt dabbers can go way up in the hoses.They almost ruined my plasma cutter.
 

aurthuritis

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pretty sure these engines vent into the intake manifold through a device built into the valve cover. should be a small cover with a spring and diaphragm underneath and a small pencil lead size passage . these can get plugged very easy with crud and quit working. if my seals were wet i would disassemble this PCV system and squirt carb cleaner through all of the passages.
 

v10rick

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pretty sure these engines vent into the intake manifold through a device built into the valve cover. should be a small cover with a spring and diaphragm underneath and a small pencil lead size passage . these can get plugged very easy with crud and quit working. if my seals were wet i would disassemble this PCV system and squirt carb cleaner through all of the passages.

Done!

The membrane was dry but dirty and distorted. Tried cleaning with carb cleaner...still warped.
A replacement is on order for the special Kubota owners price of $55 plus shipping.
 

v10rick

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pretty sure these engines vent into the intake manifold through a device built into the valve cover. should be a small cover with a spring and diaphragm underneath and a small pencil lead size passage . these can get plugged very easy with crud and quit working. if my seals were wet i would disassemble this PCV system and squirt carb cleaner through all of the passages.

UPDATE

Replaced the $55 PVC membrane. There is a small hole in its cover but that was open. This and replacing the crank seal has eliminated oil coating the front of the engine and drips on the floor.

The next leaking seal...drivers side front wheel where the half shaft enters the knuckle. According to the manual this is brake fluid but the reservoir is full.

Ordered the OEM seal, another $55 hole in the wallet.
 

aurthuritis

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not sure on your model but on mine the knuckles and rear hubs run in oil. to refill use the same as in the transmission. might as well check the wheel bearing while you are there.
 

bordercollie

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not sure on your model but on mine the knuckles and rear hubs run in oil. to refill use the same as in the transmission. might as well check the wheel bearing while you are there.

Mine too. My manual says Kubota sudt . I just change the knuckle cases and front end as part of my maintenance program. Same goes for the power steering reservoir fluid.
A skinny funnel and a piece of hose attached to it really helps fill the front differential if its in the same hard to get to place as mine is..... The new machines I don't know about though. collie

edit : http://www.nettractortalk.com/forums/showthread.php?t=17348&highlight=funnel picture of my fancy funnel and on the hood is my sophisticated record keeping. haha
 

v10rick

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Sounds like I am confused.

The half shaft mates with Front Brake Case, according to the Operator's Manual. It indicates to check the brake fluid in this Case.

Another section of the manual calls this the Knuckle Case and to use Knuckle Case oil.

Apparently there are two different halves of the same assembly. NO ? If this is so how would one know which fluid is leaking?

This is the area where my RTV900 is seeping fluid.
 
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aurthuritis

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pretty sure the brake caliper is internal of the knuckle case. it the brakes were leaking there would be fluid loss at the brake reservoir and it would leak into the inside of the knuckle. put some of the leaking fluid between your fingers and smell it to see if it smells like transmission oil. the brakes are wet brakes meaning they run in oil.
 
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