Changing prop shaft gland packing

[Nonchalant1]

I have a port prop shaft packing gland that I never touched for 2 years since I bought the boat (1978 53MY, 2" shafts), and it never leaked a drop except when the boat was splashed after 5 months in winter storage. This spring, I noticed that it wobbles when the shaft turns and it's a little off center. It still doesn't drip. I know it's the packing gland wobbling because I put a gauge stick against the shaft and it's running true. There must be a foreign object or a wad of packing material going around inside as the shaft turns. I guess I should'a thought about the gland when it DIDN'T drip, because it's probably overheated from being too tight. I hope it didn't score the shaft. When I run it at 2200 RPM, it warms up to the touch while the starboard packing gland stays cool.

So do you need to haul the boat to repack one of these? It's a 2 piece set of collars that fit one inside the other and it's adjusted by threaded bolts on 2 sides of the gland with nuts and locking nuts to squeeze the forward collar into the packing material held in the aft collar. I'd like to save the $ and do it in the water, but I've never done one. I've read the threads about rudder packing: having the right material on hand in advance, using a dentist's pick to pull the old material out, overlapping diagonal cuts in the material, etc.

I assume you just unscrew the nuts, pull off the forward collar, pick out the old stuff and reinsert the new packing material in layers, but it seems like the water pressure coming in would be pushing the new stuff out before you can get it pushed in properly.

And I'd rather not sink the boat.

Any actual experiences with this type of packing gland would be appreciated.

Thanks,

Doug

 

[dwaynec]

Doug,
Two years ago I had my mechanic change the packing in my 48 yachtfish. I had never done it before so I wanted to see how it was done with the boat in the water. I too have two inch shafts with the same collar setup you have.

Basically it looked pretty easy. As you noted he pulled the inner collar out and used a pick to pull out what was left of the old packing material. Surprisingly little water came in without the packing. It was a steady flow, but nothing that would make me think that it was a problem. Instead of cutting the packing at each round with a diagonal cut, he wrapped the packing around the shaft about three winds, cut it and shoved it in. He then did a second wrapping of about three rounds and shoved that in in front of the first wrapping. He put the collar in pretty loosly, just enough to hold it in, had me fire up the engines and then put them in gear at idle while he adjusted the packing so that it dripped about three times a minute.

Hope this helps.
Dwayne

 

[SKYCHENEY]

The last shaft that I packed was years ago on a 57' Chris Craft Constellation. As stated, it was a steady flow of water, but really quite easy after you get over the initial shock of having water running into the bilge. Good luck.

 

[Genesis]

No big deal.

Go get the GFO packing material. Expensive but worth every dime; mine is 4 years old and doesn't leak. 'Nuff said.

Yes, it can be done in the water. I've done both the mains and rudder stocks wet. Water comes in, but its not a big deal. Just make sure you have the correct packing BEFORE you start!

 

[Nonchalant1]

Thanks for the replies, guys.
Is there a "size" of packing material I should get? And what does GFO stand for?

Doug

 

[Genesis]

GFO is a goretex material - its good stuff. That's what its called "GFO" packing.

My shafts use 1/2" - both the rudders and screws.

Find it here, if you can't get it locally.

http://www.e-marine-inc.com/products/gfopacking/packing.html

 

[Nonchalant1]

Thanks,

I'll let y'all know how it goes.

Doug

 

[mike]

Doug, Call Sam's Marine. Steve McPhereson will know what size packing to use and they'll have it to sell. We've all said we'd support something for this forum, so my version is to just buy from Sam's whenever it makes sense.

 

[Nonchalant1]

Doug, Call Sam's Marine. Steve McPhereson will know what size packing to use and they'll have it to sell. We've all said we'd support something for this forum, so my version is to just buy from Sam's whenever it makes sense.

Good one Mike, I recognize it. I thought Sams wouldn't have GFO, but worth a call.

Doug

 

[Geoff58yf]

Doug one other word of CAUTION...
we have a friend with a 53my '78. Had a wobbling, leaking packing gland, stb side. He changed out the packing and tightend everything up properly. BUT, on their first cruise after (vs checking in gear at the dock) heres what happened:
the previous wobbling effect had LOOSENED THE ENTIRE PACKING TUBE on the pedro (fiberglass tube thats integrated into the hull that the whole works clamps to). It CAME OFF now leaving about a 4inch hole in the hull 3ft below the water line! and because it had spun the packing nut(s) around they smashed the glass in the raw water strainer!! (871's) another 4" water hole! in the raw water intake.
Now, in the blink of an eye, youve got about 500 gallons a minute coming into the engine room. His high water, stb side lit up first then before he could even get down below, the gen room high water lit off. At this point the only thing higher pitched than the alarms was his voice on the radio!!!
This became a serious serious problem in only minutes. He thought the (only) problem was the smashed glass on the strainer, so shut it (by reaching under water, then ran and shut the engine down. STILL not knowing or being able to see that the entire gland had spun off the tube as all his fuel manifolds are just about there. So while he thinks hes stabilized and the pumps will catch up, water is still pouring in...
Long story short, they saw the water still rising, found the tube problem and with pillows blankets etc slowed the leak til the CG came alongside with pumps. Then towed to the yard and into slings.
Anyhow Doug, point of the story is if its wobbling check EVERYTHING on the tube, including the hose clamps!! look for newly exposed surfaces to see if infact it (the hose) has moved at all.
good luck.
geoff58yf

 

[Trojan]

I would think that you would have to have the packing spinning in a bunch. With a loose glan nut,to cause the whole shaft log to run off center. Bill

 

[jim rosenthal]

OK, I'm going to be the wet blanket here.....I would not do a procedure on the boat which I hadn't done before, involving opening the bilge to seawater, without being at least once familiar with it. AT least make sure everything else is totally okay before starting this. The thing that bothers me is that this isn't a routine change of packing material- he's doing it because it's not acting right and running hot. This isn't the one to learn on, if you ask me, especially with the boat in the water.
If you're determined to do it in the water, do it at the marina and make sure they know about it so if you need an emergency haulout, you have a prayer of it. OR, do it in the lift well over lunch when they haven't got a boat in the slings, so if they need to haul you out pronto, they can do it. I realize I sound like an old lady. Sorry.

 

[Genesis]

Naw, if something goes dramatically wrong stuff a towel in there and head for a lift on the good shaft/engine. You can easily stuff enough in there to slow the water to a trickle, and if you have working pumps this is not a big deal.

 

[jim rosenthal]

OK, Karl, you are braver than I am....

 

[Genesis]

Is that or is it ?

 

[MikeP]

packing method for less water intrusion

Jim,

With some saran wrap, a towel and some duct tape, you can totally stop ANY water from coming in past the shaft while you repack. I repacked our 53's stuffing boxes this weekend. I don't think I got more than one gallon of water in the boat - total from both shafts.

I wrapped the towel with saran wrap, moved the packing gland up the shaft, wrapped the saran wrap/towel around the shaft/packing box with the saran wrap against the shaft/box and taped it. The only water that comes in occurs as you are removing/replacing the gland itself.

Actually, not that much water comes in anyway, certainly not enough to be concerned about if, as G says, the bilge pumps are working. On my previous boat I never worried about it and the amount water that came in never even raised the float switch enough to activate the pump. I wasn't sure about this with the 53 since it was my first experience with this boat but I don't think I'd bother with wrapping next time.

I used regular packing instead of GFO because there is a 50 ft spool of it on the boat. If I didn't have it, I'd go with the GFO..

 

[Nonchalant1]

My tube has a "droop" to it so the gland is not perfectly centered around the shaft. It's close to the shaft on the top and farther away on the bottom. I figured I'll loosen the aft end hose clamps and reposition the tube so it's straight when I have the packing material out to pack the gland. Maybe that's a reason to do this hauled?

Doug

 

[Pascal]

i was also aprehensive the first time around but it turned out to be pretty easy. plus on the 53MY they are easy to reach.

i used standard packing the first time around without any special tool and it took a while to get the old stuff out. It still leaked so i redid it with GFO and the proper extractor tool (flexible corckscrew...) : Much easy.

the nice thing about the GFO is that it doens't require any grease which make the hwole experience very unpleasant as that special lubircant sticks to your hands...

the port still drips a little but i don't want to overtightened it as i found that one of the 2 bolt had some stripped threads forcing me to add a second nut. not ideal but it will do for now. Shaft may have been scored in the past, we'll see whenver i have to haul out the boat.

I 'm pretty sure i used 1/2 on my 1970 53my but one package isn't enough for 1 gland. I think it took 4 rings so 3 packages neeeded for both engines. check the size of one ring, x 4, you get 30" per package

my port side gland isnt' aligned very well either but I'm reluctant to mess up with the clamps in water...

 

[Genesis]

I used three rings on my mains. I could get a forth one in there, but didn't see the need, as the three didn't leak.

 

[mike]

Just pulled our 53MY on Moday, pulled the packing today and found the same poor alignment problem. It was tight on top, lose on the bottom of the gland. When looking at the bottom I noticed that the log angle cut out is set up to accomidate a shallower angled shaft. I believe Hatt designed the log to work with both the 58' and 53' hull. The log angle appears to be set up for the 58', it may be a compromise. I will also try to reposition the log hose but I am not hopeful. By the way the log takes 1/2" packing, i am using GFO.