This is the coupler on our Newport that the Surveyor reported two weeks ago as "Good" Now it looks like we will have to haul the boat again to get it replaced. Will I ever learn?
Bazzer
Bazzer
Is this coupler ok?
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Yep, that's ugly! Also looks like your packing gland is right up against it. If that is so then there is more work to do. Probably not, but what is that up against the coupler?
Not much room I agree. The engine is not the original Atomic but now a Universal. I'm going to remove the shaft and reduce it's length, it's about 5 inches too long at the cutless bearing. The gearbox has a problem as well that's likely to need overhaul.
The coupler is so badly corroded that if you hit it with a hammer it's likely to fall apart. One of the lock bolts is spinning....
So it is the stuffing box? Then Rad has one idea, a shorter log hose is stronger anyway IF there is room to shorten it. Is there room to move the engine forward on the rails? I'd look into that option before shortening the shaft. And a flexible shaft saver, about 1/2" in thickness would be cheap insurance. But you will need the space.
Attachments
There is quite a bit of meat to these couplings. From your picture it looks like it might be surface corrosion. You can chip around on the coupling to get some idea as to how deep it goes. If its not too deep I think I would put it on my to do list for the next time I hauled the boat. Of more concern to me would be how close the packing gland is to the coupling. If its rubbing, that's not good. If your packing gland can stand tightening that's what I would do for a little more clearance.
Yes, the hose can be shortened quite a bit. The shaft extends beyond the cutless bearing by about six inches, no vibration but definitely to long. If I have to haul the boat then I will get it shortened. The engine can't be moved forward, but the gearbox will also have to come out. Again, the surveyor missed the fact that there was no oil in it! Now it jumps out of forward gear. I wish mine looked like yours Ed. What kind of anti-vibration coupling are you using?
Bazzer
There is at least 1/4 inch of corrosion on the surface of the coupling, more than I am comfortable with. One of the lock nut female threads is striped as well.
Bazzer
You've got
You've got some good advice thus far. Here are a few things out of the ABYC P-6 prop shafting standard to be aware of when re-assembling everything (this is not law but a good minimum standard to follow):
6.5.5.4 The distance between the forward end of the
propeller hub and the aft end of the last strut bearing shall
be limited to one shaft diameter.
6.5.5.3.1 Alignment shall be accomplished with the boat
floating.
6.5.5.3 Bearings, shaft, and couplings shall be aligned to
a tolerance of no more than .004 in. (.102 mm) measured
between the parallel flange of the coupling with the
coupling bolts loose.
6.5.5.2 If a non-conductive flexible coupling is used, an
alternative means of grounding the shaft must be provided.
6.7.1 Shaft seals shall be readily accessible.
6.7.3 If a shaft seal utilizing replaceable packing
material is installed in the boat, it shall have clearance
along the shaft line to permit replacement of the packing
without uncoupling the shaft or moving the engine.
P.S. I'm very surprised any surveyor would not have picked up on missing seizing wire on the coupling set screws???
You've got some good advice thus far. Here are a few things out of the ABYC P-6 prop shafting standard to be aware of when re-assembling everything (this is not law but a good minimum standard to follow):
6.5.5.4 The distance between the forward end of the
propeller hub and the aft end of the last strut bearing shall
be limited to one shaft diameter.
6.5.5.3.1 Alignment shall be accomplished with the boat
floating.
6.5.5.3 Bearings, shaft, and couplings shall be aligned to
a tolerance of no more than .004 in. (.102 mm) measured
between the parallel flange of the coupling with the
coupling bolts loose.
6.5.5.2 If a non-conductive flexible coupling is used, an
alternative means of grounding the shaft must be provided.
6.7.1 Shaft seals shall be readily accessible.
6.7.3 If a shaft seal utilizing replaceable packing
material is installed in the boat, it shall have clearance
along the shaft line to permit replacement of the packing
without uncoupling the shaft or moving the engine.
P.S. I'm very surprised any surveyor would not have picked up on missing seizing wire on the coupling set screws???
I agree that 6" past the cutlass is too far out there. One thing to watch out for is your prop clearance with a shorter shaft. The PO may have used a longer shaft to allow for a larger diameter prop. The coupler is toast but they aren't that expensive; not in the light of a boat haul anyway. Tightening the nut will not move the packing gland enough to make a difference. The packing gland should be tightened only to adjust the drip. If you tighten it to move it away from your coupling and it is adjusted properly already then you will burn up your shaft.
IMHO, moving the engine would be the last thing I would do to make clearance. I would shorten the stuffing box hose as much as possibe and if that wasn't enough I would see if a custom made coupling could give a little more room. I just had a stainless coupling made, I think it cost twice what I could have got a regular one for though, like $140.
Look up an article Maine Sail did about teff gel. I haven't got my shaft and coupler installed yet but when I do in the next month I will definitely use teff gel.
IMHO, moving the engine would be the last thing I would do to make clearance. I would shorten the stuffing box hose as much as possibe and if that wasn't enough I would see if a custom made coupling could give a little more room. I just had a stainless coupling made, I think it cost twice what I could have got a regular one for though, like $140.
Look up an article Maine Sail did about teff gel. I haven't got my shaft and coupler installed yet but when I do in the next month I will definitely use teff gel.
Suggestions
Do yourself a favor. Do it yourself and replace everything...coupler (I suggest a split coupler for easier mounting and removal), shaft, hose, cutless bearing and stuffing. The stuffing box looks pretty good, but lots of proponents of dripless boxes here, so consider it.
I had all my stuff reconditioned by a marine machine shop. Nice work, but new was essentially the same price.
Pressing your shaft out of the coupler ala Good Old Boat, works fine, but is time consuming. Cutting things out and tossing them (after you measure them of course) will be faster, but you will need the right equipment to cut through the coupling. I thought about trying to cut the shaft, but was told it is much tougher to cut through.
Do yourself a favor. Do it yourself and replace everything...coupler (I suggest a split coupler for easier mounting and removal), shaft, hose, cutless bearing and stuffing. The stuffing box looks pretty good, but lots of proponents of dripless boxes here, so consider it.
I had all my stuff reconditioned by a marine machine shop. Nice work, but new was essentially the same price.
Pressing your shaft out of the coupler ala Good Old Boat, works fine, but is time consuming. Cutting things out and tossing them (after you measure them of course) will be faster, but you will need the right equipment to cut through the coupling. I thought about trying to cut the shaft, but was told it is much tougher to cut through.
4 1/2" angle grinder, a Norton, or similar, metal grade cut off disc and about 30 seconds....
Got one, and since the hose and shaft both need shortening, not a problem. The only problem is that I have to lift the boat high enough to remove the Rudder.4 1/2" angle grinder, a Norton, or similar, metal grade cut off disc and about 30 seconds....
Bazzer
Only of you are on asphalt. If your over dirt you simply dig a hole to drop the rudder into..
Shaft Coupler May be OK
Even though it is ugly and rusted it may be fine. Your statement that one of the locking bolts spins indicates it is stripped out and that may be cause to replace the coupling. I also agree that you may want to reduce the length of the tube or move the engine forward as you have too little clearance there. Shame on the surveyor - "good" sounds like a CMA statement. The recommendation for a shaft coupler is a good one - I put a PYI coupler on mine that I am very happy with.
Even though it is ugly and rusted it may be fine. Your statement that one of the locking bolts spins indicates it is stripped out and that may be cause to replace the coupling. I also agree that you may want to reduce the length of the tube or move the engine forward as you have too little clearance there. Shame on the surveyor - "good" sounds like a CMA statement. The recommendation for a shaft coupler is a good one - I put a PYI coupler on mine that I am very happy with.
If you are not going to cut the shaft off, then first step is to remove/drill out the locking bolts on the sides and get going with your soaking of PB Blaster squirted in the holes.
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