Inboard Shaft Seal

[351 OMC]

Bought the 2000 27' Sport Craft Inboard last Aug. Noticed some water seeping out of the seal where the shaft comes thru the hull. Also noticed some water coming up thru the shaft on the rudder when in the water. Are these pretty easy fixes or do they require special tools and skills? My Mercruiser book does not cover this. Thanks for your time. JEC

 

[QC]

Re: Inboard Shaft Seal

Well there are a couple of different types of seals, and you treat them/repair them differently. Considering both are weeping and/or leaking then I am kinda thinking they are both packing seals. These use a jam nut to squish some greasy string (major simplification)around your shafts . . . They can be adjusted by tightening or loosening, and they can be replaced without anything real special. On the rudder they say to crank it down until there is some resistance on the wheel. On the propshaft, you are supposed to adjust until you get a couple of drops a minute, but I'll confirm that rate. If they are dripless seals, then forget everything I just posted.

I'll get you a couple of good links. You should probably get us some pictures or a little more info . . .

 

[QC]

Re: Inboard Shaft Seal

Here's a link that explains how packing seals work etc . . .

Inboard packing seal stuff

 

[steelespike]

Re: Inboard Shaft Seal

All the boats I've had used packings something like oldfashioned faucet packings.A nut a gland and graphite packing.Sometimes you can just tighten the nut.On the drive shaft never over tighten.Its better to have just the slightest drip too tight can damage both packing and shaft.Don't over tighten
the rudder packing either.Its been at least 20 years since I worked on a shaft packing.Its possible modern packing is now teflon or other state of the art material.Packing replacement is a pain ,you have to pick out the old stuff.
No real skill involved just some sort of tool fashioned to dig it out.should be done when hauled out.Rudder may need support to keep it out of your way.
If you have to take the arm off definately support.

 

[arks]

Re: Inboard Shaft Seal

The tool to remove old packing is called a "packing extractor" and looks like a small corkscrew. Packing comes in different sizes, so it's very important to get the correct size for your vessel.
The latest -and best- packing material out there is called GFO and works great. I have installed it on my boat and it installs exactly like conventional packing. No leakage AT ALL, and I've been using it now for 2 years without any adjustments. Google "GFO by Gore" and the national supplier is at the top.