Prop shaft nightmare
Posted: Mon Nov 06, 2017 4:15 pm
Last year I replaced my shaft, cutless bearing, shaftseal and engine mounts on my Yanmar 3jh3e (F38). I did all the work myself but I paid to have the engine aligned ($250) by the marina when it was launched. I asked the head mechanic if it was aligned and he said I did such a good job he did not have to adjust anything. I then asked him if he tightened the hold down nuts on top of the mounts and he said yes (I did not torque them down tightly because I knew the shaft had to be aligned). I peaked at the engine and it seemed fine but I did find a 10 inch crescent wrench that I gave back to the mechanic.
I used the boat for two weeks then one day while motoring back to the harbor (about 2700rpm) after a race I hear a loud squealing sound. It was so loud that at first I thought it was a police boat siren. I backed off the throttle and realized it was coming from the engine compartment. When I looked my new Tides marine shaft seal was twisted out of alignment and leaking rapidly because the hose was tightly twisted around the shaft. I un-jammed the seal which reduced the leaking to simply dripping and motored back to the mooring slowly.
Once back at the mooring I inspected the engine and found the engine severely out of alignment. Three hold down nuts were in the bilge causing the bottom adjustment nuts to spin down causing the shaft to be out of alignment which in turn caused the shaft seal hose to grab the shaft. I am surprised (lucky) that the Tides seal hose did not fail!
I talked to the manager of the marina to at least get my money back but he said I should have inspected the boat after a couple of weeks! I explained the significance of the wrench, that you can't tighten those screws properly with that wrench but he was obstinate and defensive. So I gave up and I simple will never do business with them.
I removed the Tides marine seal and inspected it. The plastic was worn so it was no longer round causing it not to sit properly and leak. I chose to replace it with a Norscot seal. It is made of bronze and has three seals as apposed to only one in the plastic Tides seal. It does require a ATF lubricant but after a whole season I only used a couple of ml. It is even more compact than the Tides so it fits nicely in the tight space in the F38. I aligned the engine and tightened the hold down bolts properly with a breaker bar!
Michael Belanich
Dolcetto F38 #65
I used the boat for two weeks then one day while motoring back to the harbor (about 2700rpm) after a race I hear a loud squealing sound. It was so loud that at first I thought it was a police boat siren. I backed off the throttle and realized it was coming from the engine compartment. When I looked my new Tides marine shaft seal was twisted out of alignment and leaking rapidly because the hose was tightly twisted around the shaft. I un-jammed the seal which reduced the leaking to simply dripping and motored back to the mooring slowly.
Once back at the mooring I inspected the engine and found the engine severely out of alignment. Three hold down nuts were in the bilge causing the bottom adjustment nuts to spin down causing the shaft to be out of alignment which in turn caused the shaft seal hose to grab the shaft. I am surprised (lucky) that the Tides seal hose did not fail!
I talked to the manager of the marina to at least get my money back but he said I should have inspected the boat after a couple of weeks! I explained the significance of the wrench, that you can't tighten those screws properly with that wrench but he was obstinate and defensive. So I gave up and I simple will never do business with them.
I removed the Tides marine seal and inspected it. The plastic was worn so it was no longer round causing it not to sit properly and leak. I chose to replace it with a Norscot seal. It is made of bronze and has three seals as apposed to only one in the plastic Tides seal. It does require a ATF lubricant but after a whole season I only used a couple of ml. It is even more compact than the Tides so it fits nicely in the tight space in the F38. I aligned the engine and tightened the hold down bolts properly with a breaker bar!
Michael Belanich
Dolcetto F38 #65