Yanmar Front Engine Oil Seal Leak

[Surfnski]

I have a Yanmar 4JH2-UTE in my Whitby 42. The engine has 2500 hours on the meter. I have a small oil leak from the front engine seal. Oil drips onto my absorbent pad and also weeps onto the v-pully causing a splatter to the sides. Ideally, I would like to wait another 500+ hours before dealing with this minor issue unless it gets worse. Is the leak rate likely to increase over that time? How difficult is this to repair?

Thanks in advance for your informed opinions!

Surfnski
s/v Alembic


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[model 10]

As it's starting to leak it's also starting to wear a groove in the damper. The oil collects dirt and there you go. Pulling a damper is not a big deal if you have a puller. Removing the cover is just nuts and bolts. The seal will punch out with a big socket or rip it out with a screwdriver or something. All easy if you have access.

[westwinds]

You might consider seal softener available at your local automotive parts store. I have used it on an old automotive engine and got another 20,000 miles (500 hours).

[Lepke]

If you let it go long enough, moisture will collect along the seal/shaft and put pits in the shaft. Pits will then eat up any new seal in a short time.

[a64pilot]

Do not use the leak stopper stuff, unless your doing a complete rebuild in that 500 hours you want to wait, that stuff softens ALL the rubber in the engine.
Front seal is easy to replace, much easier than say, the rear seal, I wouldn't wait, leaks never get better


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[Surfnski]

I had a mechanic look at it today. He thinks he can pull the seal without removing the gear case cover by threading screws into the seal and pulling. He thinks if this does not work he will have to pull the engine to drop the oil pan. From my read of the engine breakdown, only the front 6 bolts of the oil pan go into the gear case cover. It looks possible to pull the cover by removing these 6 bolts and then the remainder of the bolts holding the gear case cover to the engine block.

Has anyone pulled a gear case cover from the front of the Yanmar without dropping the oil pan?

[model 10]

He should know which way the seal goes before he tells you he might need to drop the pan. If it comes out the front and he can't do it, you need another mechanic.