oberdorfer shaft seals ?

[HalcyonS]

Hi all
after an overheating adventure recently, I found my impeller bladeless! And one of the blades lodged in the water inflow T, where it must have been pushed by a remaining blade. Replaced impeller. Started up and had water fast-dripping out the 'drain' hole between the shaft seals. Greased the shaft, and it cut the leaking down to zero - temporarily. I'm assuming I need new shaft seals.

So I got new shaft seals from MM, but they were both the same size. And the image in my service booklet shows them as different - see pic.Its kinda small,but the engine side one is wider dia, and appears to sit on a shoulder cut into the pump body.

So - questions:
1. Did I get the wrong seals for my pump body?
If so what is the part#/description of the pump I have and the right seals (see pic2+3)

2. How do you change the seals? Needs a special tool, no?

thanks!
Simon

[Administrator]

From Don:

The "Service Booklet" this person refers to is the little yellow Atomic 4 Service and Repair Manual published by Seacraft Publications many years ago. That Manual contains a cross-sectional sketch of a water pump, and it does (incorrectly) show the seals as being a different size. The sketch is somewhat generic, but it is on a page following a photo of an Oberdorfer pump, which is probably why this poster assumes that the sketch is for an Oberdorfer. In reality, all of the brands of pump used by Universal over the years (Jabsco, Sherwood, and later, Oberdorfer) have two identical lip seals.

Bill

[HalcyonS]

thanks to Don and Bill for this reply. Yes indeed, the image was from the little yellow book.

" The sketch is somewhat generic, but it is on a page following a photo of an Oberdorfer pump, which is probably why this poster assumes that the sketch is for an Oberdorfer. " That is what I assumed.

"In reality, all of the brands of pump used by Universal over the years (Jabsco, Sherwood, and later, Oberdorfer) have two identical lip seals. " OK, good to know I have the correct seals.

Now to find out how to replace them.

[Al Schober]

Simon,
The outer seal (toward the engine) will just pry out. The inner seal is a bit of a problem. I made a tool from a old screwdriver - heat up the end with a propane torch and bend it over to about 70 or 80 degrees. This tool goes down through where the shaft goes and will engage the inner seal, allowing you to drive it out. Usually works..
New seals are just pressed in using a socket. The lip on the inner seal should be towards the impeller, while the out seal is the other way.
Before you spend a lot of time on it, check parts for wear. Grooves in the shaft, shaft loose in housing, wear of parts that rub on the impeller (including the cover) are things to check.
Best..

Al

[Marian Claire]

Chances are the new seals will not look like the old seals you take out. The new ones are all plastic/rubber compared to the old ones with a metal outer cover. I find it easy to drive the oil seal in to the pump a little bit and then take a flat screwdriver and coming thru the drain port crush the seal for easy removal. The water seal is a bear. Just go slow and try not to bugger up the pump housing. Dan S/V Marian Claire

[HalcyonS]

thanks for replies, guys!

> Chances are the new seals will not look like the old seals you take out.

right. Old ones are brass. New ones are butyl or something, with springs inside. So installed the spring sides face each other - i assume.

> I made a tool from a old screwdriver - heat up the end with a propane torch and bend it over to about 70 or 80 degrees.

right, something with a lip/hook about 1/8" I guess - shouldn't be to difficult. Actually, a paint can opener might do it?

> New seals are just pressed in using a socket.
good trick

> Grooves in the shaft,

good point. Shaft is smooth except for an area of pitting - I hope its not under a seal - might explain my problem!

So between the impeller and the seal, the only thing that keeps water out is the grease. interesting. I wonder why there isn't a seal right behind the impeller?