Dripless Shaft Seal Question

[jackryan]

I have my 1978 31 Flybridge on the hard for a bottom job and general maintenance. I can spin the prop with my hand, but it does not spin easily, and it makes a grinding noise at the dripless shaft seal. I know that the dripless is lubricated with water, and since the boat is out of the water, the dripless is not lubricated. My question is, should the shaft spin freely, and is it normal to hear a grinding sound at the dripless shaft seal. Is there any annual maintenance involved with a dripless shaft seal?

Thanks!

JR

[jackryan]

The old lady is looking pretty good. This pic is right after the haul out. Since then I've (with some help from my brothers) painted the bottom, wet sanded, compounded, polished, waxed the exterior gel coat, sanded the rub rail and torn out the entire convertible dinette area. I have a leak from the port side windows and water ruined the floor under the dinette table. (the floor and sub floor were very hard to remove) I'm going to have to finish that project after splashing her. Today I'm going to prime and paint the rub rail with Interlux Brightside. I'll try to post an "after"picture later.



JR

[jackryan]

I'm supposed to splash her this afternoon, but wanted to address the dripless shaft seal issue with the yard before I do. My brother thinks there is a chance that it's normal that you hear a grinding sound from the dripless when out of the water because there is no water to lubricate it. Its not a pretty sound and that coupled with the fact that the shaft does not turn freely (it does turn, but with some effort) is the issue.

Thanks,

JR

[Kevin]

JR,
Spray some water on it before you splash it and turn it. The stainless ring on the graphite should not make any noise wet or dry with hand turning as my boat sits on a lift. I suspect the noise could be shaft touching the tubes since the boat is on the hard and likely out of alignment. Visually look up shaft into tubes and see if it is touching. Probably be fine once in water sitting with no abnormal pressure points on hull unless mounts are worn or broken.

[Bruce]

There should be no grinding sounds comming from the glands even dry. It could be barnacles inside the boot/shaft , shaft/tube(rubbing on side) space dried out and breaking up.
The only friction against the collar on the shaft and the carbon seal is the pressure of the rubber boot compressed. Which is really nothing.

Your boot from the pics appears to have cracks. If so it needs replacing.

[Pete Fallon]

Jack,
I agree with Bruce, it looks like the dripless seal has some cracks and is mis-shappened, there shouldn't be any noises coming from the seal when it is turned by hand. Check the water supply hose to see if there are any debris in the hose from old pieces of zinc. I have surveyed a few 31's that the feed hose came off the Yanmar tranny cooler and the hose was completely blocked with old zinc pieces.
Pete Fallon

[jackryan]

Guys,

Thanks for the responses. I had a mechanic take a look at them yesterday. Exactly as you guys said, there were a few barnacles and the shaft was touching the tubes due to being on the hard. As always, great advice and insight.

Many Thanks!!

JR