shaft log repair/replace...

Well the generator has been unbolted, disconnected and moved to the side and tomorrow she gets pulled for the shaft log repair or replacement. I've been dreading this job since I bought her. Hopefully I'll be able to figure out how best to fix it, as no one I've talked to really knows exactly what I should expect to find for sure. However, thanks for the info that has been given. Hopefully some of it will look familiar otherwise it's sort of like going in blind, but actually that's what I did buying her in the first place! ...I'm beginning to miss my rags...

MYMT,
What are the symptoms of your problem? I see your post is #1.

Sorry it took so long to respond. I've been up to my ears with this job! The shaft log is embedded in concrete (I was afraid that would be the case) Regardless, the area behind the packing gland housing has been seeping water into the bilge for the last couple years (probably longer) So either the water intrusion was coming from a bad seal where the cutless bearing housing bolts onto the keel, or the shaft log is leaking. The cutless housing was supposedly rebedded when I bought the boat, but now that its out of the water and I've looked at it, I'm not sure it was sealed very well. So for the last two days I've been disconnecting the packing gland housing, the cutless bearing housing, I've got a hole in the rudder that is supposed to accomodate removing the driveshaft, but the hole does not come close to lining up with the shaft. So I took the rudder off completely, which wasn't easy as I could not raise the rudder post enough to remove the rudder. I finally got it done by partially dismanteling the rudder housing under the cockpit. And its in the 90's with high humidity and it'll be a miracle if I can get this done. BTW, is there any other way to remove the coupler from the drive shaft other than using a slide hammer? I found that the shaft log is sealed at the packing housing by use of a gasket at the bulkhead. The cutless housing is off, but there is a base plate that was between the housing and the keel, and I'm not sure how that is connected to the shaft log, or if it is actually part of the shaft log. I need to get the drive shaft out before I can continue with the rest. This is a damn big job!...

There are a number of ways to remove the coupler. You can push the shaft out by putting a long socket or piece of pipe between the shaft end and tranny coupler nut and using threaded rods and nut to squeeze the two together and push the shaft out of the coupler.

Whatever you do make sure the set screws are out of the couple. And you should replace the coupler and not reuse the old one. I would go with a split one. They are easier to remove.

Thanks for the info Capt Bill. i need to buy longer bolts to use a socket. Why should you not reuse the coupler? And where would one find a split coupler to fit the other half coupler that is still on the transmission?

I heard it said that even just a smattering of rust inside a coupling makes it not reusable due to tolerances....though many do with no ill effects especially with slow turning trawler engines.

I just took my shaft to a machine shop that specialized in marine work and they got me a split coupling and matched it to my shaft...they also fixed the pitting that was in the area of my stuffing box that pitted from lack of O2.

Compass marine has a tutorial that covers removing a shaft coupling.

PSS Shaft Seal Installation Photo Gallery by Compass Marine How To at pbase.com

There may other lessons here that would help you.

"I just took my shaft to a machine shop that specialized in marine work and they got me a split coupling and matched it to my shaft...they also fixed the pitting that was in the area of my stuffing box that pitted from lack of O2"

Thanks psneeld, this is just what I need to do. And angus99, the information in that link you provided was very informative. ( How come I can never find articles like this?) The help that you guys provide is very much appreciated!!
...off now to get that blasted shaft off!!

For the record...I've been told to always take ANY new coupling with your shaft to be trued....hard to imagine they could be that far off but when the same people say never reuse a solid coupling...the rust affects the trueness...well I gotta wonder.

There's probably countless boaters and commercial guys that reuse couplings and certainly split ones and don't take the setup to a machine shop everytime....gotta wonder....

psneeld said:

For the record...I've been told to always take ANY new coupling with your shaft to be trued....hard to imagine they could be that far off but when the same people say never reuse a solid coupling...the rust affects the trueness...well I gotta wonder.

There's probably countless boaters and commercial guys that reuse couplings and certainly split ones and don't take the setup to a machine shop everytime....gotta wonder....

Click to expand...

As I recall split ones are designed to be reused. The problem with trying to reuse a solid one is that between truing up the shaft end and the inside sleeve of the coupling you can end up taking off enough material that the old coupling would be loose on the shaft.

This is what the coupler on the end of the shaft looks like. Can anyone tell me what the two half washer looking things are for? They turn and are somewhat lose. They appear to extend a ways inside so they are not 'flat' washers so to speak. There also does not appear to be a groove that they sit in on the coupler. Any help would be much appreciated
Thanks

I'm thinking they have to be like valve keepers except for the shaft. Tapered down and probably sit in a groove in the shaft that keeps them from coming out. Don't know what else they could be. Which means the coupler will have to be moved aft to remove these, then the coupler should be able to come off. Does this make sense to anyone else?

Yes. By your description it looks like some kind of split tapered bushing.

Sounds right to me.

If you are going to install a new coupler, consider installing one of these:

Federal Flexible Couplings

http://www.sealandpower.com/Driveline Parts & Access/Federal Flexible & Standard Couplings(2).pdf

Does anyone know of a tool or procedure to get this sort of coupler off?

I used a 4 inch grinder with a cutting disc...took about 2 minutes...cut down and aligned with the key so you don't cut into the shaft. Lots of sparks, post a fire watch.

I was going with a split coupling so I would never have the problem again so trashing the old coupler was OK with me. The time, effort and frustration working in a limited area just wasn't worth the couple hundred for a new coupler and then another 300 to have it matched and the shaft flamed sprayed (I think that's what they called it) to fill in the pits from the old packing.

Any yard might have charged $500 just to get the coupler off.

Should have taken your advice two days ago psneeld, ended up cutting it off with a circular saw and a metal cutting disk.
I now know what a shaft log looks like, how it's connected at both ends, what black rotten fiberglass-wood-whatever else smells like, and how the whole thing was put together. Most importantly I've learned that replacing and repairing a non serviceable item such as this is, should never be attempted by a sane person because it will undoubtably make you crazy!!!

MYMT said:

Should have taken your advice two days ago psneeld, ended up cutting it off with a circular saw and a metal cutting disk.
I now know what a shaft log looks like, how it's connected at both ends, what black rotten fiberglass-wood-whatever else smells like, and how the whole thing was put together. Most importantly I've learned that replacing and repairing a non serviceable item such as this is, should never be attempted by a sane person because it will undoubtably make you crazy!!!

Click to expand...

some of us are pathfinders and the rest are ....."lucky!!!!"

...that is the single most valuable thing I get from these forums...finding out who has explored the unknown before I have to go there....I'd rather be the "lucky one" than the pathfinder and sometimes it takes weeks exploring the internet...but a few times it's REALLY paid off for me.

the ones that always say..."let the pros do it" or that's not "ABYC" are the most frustrating to have to deal with....as far as I'm concerned...they are just wasted bandwidth....

my go to tool on the boat is my 4" grinder..its done everything from strip my bottom to cut off the coupler to sand, shape, etc...etc...not a pretty finish all the time but the better you get with it...the more surgical it becomes.