Fitting PYI Flexible Coupling

[duck21]

Hi all,
I measured and determined a split coupler would fit on my Hunter 376. Today I attempted an install but ran into a bit of an issue -- the coupler fits, but I'm unable to wiggle the bolts in between the shaft coupling and the transmission flange.

I considered removing the shaft coupling, pulling back the shaft, installing to the transmission flange, then reconnecting everything but given the space this would mean that I would not have room to back off and access the packing nut should I have a leak/need to replace the packing (that is, with out having to pull the prop shaft from the shaft coupler, which would be difficult when in the water).

I will try shorter bolts, but I'm not sure that there is enough room even for those (while still leaving enough room to properly thread the nut). There is also not enough room to feed in the bolts from the transmission side.

I'm wondering if others have run into this and if there is a "trick" or procedure that I'm not considering to make this work. Or, maybe I'm just out of luck (but I'm hoping to find a way to make this work).

I've included some pictures for reference, in case that's helpful.

Thanks!
Doug

 

[JoeWhite]

Is the white part a damper plate? If so , will it work without it?
It appears that you could shorten the hose by 1" and not suffer any consequences.

 

[Jan_H]

A Volvo dripless shaft seal would solve the problem. Easy to install since you already have the split coupler.
Jan

 

[duck21]

The white part is the flexible coupling I'm trying to add. My original setup did not include it, but they are supposed to run quieter and reduce wear and tear on the Cutlass bearing, as well as reduce chances of damage if the prop is fouled.

I'll have to measure and see how much extra space is available between the hose barba there. I might be able to gain .5+ inches.

Doug

PYI Inc. | Flexible Shaft Couplings

The R&D Marine Flexible Coupling fits between the transmission output flange and shaft coupling. It is designed to protect a boat's drivetrain.

www.pyiinc.com

Doug

Is the white part a damper plate? If so , will it work without it?
It appears that you could shorten the hose by 1" and not suffer any consequences.

 

[dlochner]

The split coupling from PYI is heavy duty and a bit longer than split couplers from Buck-Algonquin and other companies. That and the addition of the flexible coupler exceed the space available. This will make it difficult to adjust the stuffing box as you have learned.

To solve the bolt issue, insert the bolt from coupling side with the nuts between the transmission flange and the transmission.

 

[Tally Ho]

I replaced my original stuffing box with a Volvo dripless seal. I did it because I wanted a dry bilge, but in your case, it would provide you with a significant amount of space…

And you would have an added benefit of a nice dry bilge!


Greg

 

[BigEasy]

I replaced my original stuffing box with a Volvo dripless seal. And you would have an added benefit of a nice dry bilge!

That picture says it all!

Doug, The Volvo or Radice seal would solve your problem inexpensively, only $140.
with relatively simple installation.
Greg, Just curious if you have a water injection nipple on your setup. My Volvo shaft seal works great! Nice having a dry bilge & no need for stuffing box adjustments; however, I developed a leak where the nipple fits into the FRP shaft log. Just removed the nipple for inspection, in July, when I replaced the 17 year old VOLVO seal. I usually do one wrap of Teflon tape & 4200 that works satisfactorily (when installed dry). Really didnt want to haul out for this, so I removed nipple (yes there is water flow into shaft log from internal cutlass bearing, but not a flood). Retaped nipple & coated with Sea Goin underwater epoxy paste & reinstalled. So far, so good…..no leaks. Haven’t run motor in gear yet, so final test to come. Regret not installing a Radice seal that has nipple incorporated into the seal; no need for nipple into the FRP shaft log.

 

[duck21]

I'm liking the Volvo dripless idea. I'm going to order one up and see if it gets here before spring launch! (Otherwise I'll stick with the direct bolt setup for this season and do the swap next year).

Thanks for the advice everyone!

Doug

 

[Tally Ho]

That picture says it all!

Doug, The Volvo or Radice seal would solve your problem inexpensively, only $140.
with relatively simple installation.
Greg, Just curious if you have a water injection nipple on your setup. My Volvo shaft seal works great! Nice having a dry bilge & no need for stuffing box adjustments; however, I developed a leak where the nipple fits into the FRP shaft log. Just removed the nipple for inspection, in July, when I replaced the 17 year old VOLVO seal. I usually do one wrap of Teflon tape & 4200 that works satisfactorily (when installed dry). Really didnt want to haul out for this, so I removed nipple (yes there is water flow into shaft log from internal cutlass bearing, but not a flood). Retaped nipple & coated with Sea Goin underwater epoxy paste & reinstalled. So far, so good…..no leaks. Haven’t run motor in gear yet, so final test to come. Regret not installing a Radice seal that has nipple incorporated into the seal; no need for nipple into the FRP shaft log.

I do not have an injection nipple on my set up. My seal is right next to my thru hull for the engine cooling water, so when I open the thru hull before starting the engine, I give the seal a little squeeze to bleed any air out.

these photos show the progression of my journey…
original shaft & stuffing box. Then new shaft and painted bilge, but old stuffing box, and finally, with Volvo shaft seal.


Hard to find it, but the thru hull handle for the engine and head intakes are down there, so really easy to give the seal a squeeze before heading out.

@BigEasy If the nipple is in the stern tube, how does that release air in the end of the seal? Isn’t the engine side of the seal higher than where it attaches to the stern tube? I thought about trying to drill a hole in the rubber part of the Volvo seal and stick a nipple in there, but don’t really want to create a problem I don’t need to fix at this point.

Greg