Leaking Oil

[ghebbns]

Hi all,
I have an oil leak that has developed this season.  No problem last year.  After motoring for at least 20 minutes, I notice a trail of oil underneath the engine.  I have attached a couple of pictures to show the positioning of the leak.  Best I can tell, it is coming down the port side of the engine (as indicated on the picture). Any idea of the source of the leak?

Thanks

[KWKloeber]

Port side on the older engines there's two prime locations for leaks:

1) the plug that seals off the port-side oil dipstick hole thru the engine block.  Fwd port, in behind the alternator and exhaust manifold.

2) your leak - the Low oil pressure switch;  above the starter, in behind the exhaust manifold.

-k

[KWKloeber]

PS: put your engine info in the sidebar profile or signature.

[ghebbns]

Thanks. And the fix is??

[KWKloeber]

The fix is to:

Click on your display name in the sidebar
Click on Forum Profile
Enter your particular engine data.
Save.

-k

[KWKloeber]

Oh, you mean the oil?

Find out why it's leaking. Loose switch?  Failed?
Tighten or replace.

Hopefully, that's the location and not something more serious.  But the oil switch is above the starter near the bell housing, so that's the likely spot.
See your parts manual for the location. 
See the Wb Service Bulletins (Wiki) for a note about removing
See Ron's (I think?) article (Tech Notes) re: the socket to use. 
Search the forum -- there are other's pix and trial/tribulations re: getting at and replacing that darn switch.
The cross-reference Kubota part number for the switch is also in the posts, might be on the Wiki also. 

-k

[Ron Hill]

gheb : If it is the oil switch look in the Mainsheet tech notes and you'll find (as Ken mentioned ) the size of the socket, but also the epoxy fix that I painted on the switch - to seal the joint where the metal meets the Bakelite body.
That's where it usually leaks and don't overtighten the new switch on the engine block.

A few thoughts

[ghebbns]

Thanks Ron and Ken.  I have a new one on order (from Kubota) and it should be here in 1-2 days.  I am hoping it is not too difficult to get the old one off - I see that some people in the forum have had some troubles.  I have printed off Ron's Mainsheet article so I am sure that will help.  I will let you know how it turns out.

[ghebbns]

Well the new oil switch arrived.  Not a fun job changing it, but I did it.  Started the engine and let it idle around 1700 rpm for 10 minutes or so.  To my dismay, still had the oil leak (see attached photo).  It seems to be coming out from the bottom screw of the starter.  I checked the new oil switch and no leak there.  Also didn't seem to be any oil above the bottom screw.  Any ideas? I think it might be time to call in the experts.
Thanks

Greg

[KWKloeber]

Greg

Have you looked to see if the rocker arm cover gasket is leaking and it's dripping down onto the starter?

Put paper towels in different locations so see which location intercepts the oil first.
I'll check the service manual to see if there's anything else in that area that might leak.

-k

[ghebbns]

Thanks Ken, I really appreciate all the help. As I am sure is obvious, I do not have much mechanical ability but I want to try as much as I can before I get a real mechanic ($$$).

G

[KWKloeber]

I think you're looking at oil running past a bell housing bolt.

There are three things located above that general area, the oil switch (failed switch or leaking thru the threads,) the valve rocker arm cover (leaky gasket), the head (warped head, oil leaking past the head gasket.)  Had she overheated?

There's no oil passages in the exhaust manifold, no oil in or against the starter, or against the end plate (that the bell housing and starter bolts onto). 
If was the rear main crankshaft seal leaking, I would expect oil to end up in the bell housing, not dripping down the engine block or starter.
Next in my line would be the valve cover gasket.

I'd say if you could replace the oil switch as difficult as it is on the 34, you have enough mechanical ability and tough knuckles to do about anything on an M-25/XP.  It's just knowing what to do, not so much doing it.

I'll toss the leak question out to the C30 folks.

RON ??!?!??

-k

[KWKloeber]

Greg

Another thought, that isn't a good news thing, unfortunately. 

If the rear main crankshaft seal was leaking, I suppose, theoretically, the flywheel (rotating inside the bell housing) could be slinging oil up and against the starter motor pinion that extends into the bell housing and engages the flywheel gear teeth. Then oil could make its way out thru the hole in the rear plate, get between the rear plate and starter housing, and drip down past the starter bolt.

Look at pg 122 of the XP Technical Manual (Service Manual) -- on the right-hand pix (flywheel removed,) you can see the ass end of the crankshaft.  The rear main seal (lower pic) is the dark ring that sits inside the bearing case cover.  The hole that the starter pinion enters is shown in that pix and the upper right pix.  This is all theoretical, cuz I've no first-hand knowledge of rear seal leak issues on the XP, but it seems plausible.  There are two rear seals -- one labeled "oversize", so maybe that's to fixemup a leaky seal issue -- dunno?

You might talk to an engine service manager at Hansen Marine in MA, or at Engines1 (Western Branch Diesel, VA, NC (both Westerbeke marine dealers) who may be aware of or previously diagnosed a seal problem from your symptoms.

-k

[KWKloeber]

Greg

A 30-er had an excellent thought; pull the starter to see if you find engine oil on the pinion and/or inside the dome (the aft end of the starter that you can see and bolts to the end plate.  Our starter it pretty easy to do, ping if you go that route and need instructions.

-k

[Ron Hill]

Guys : If you have a leak in the rear crank seal, you'll have a bunch of oil coming out of the rear & bottom of the bell housing by the drive shaft- been there and replaced that!!


A thought