I had a new Universal/Westerbeke diesel installed several months ago, it has about 50 hours on it now.
From the beginning, there was a very unpleasant vibration at low idle rpm. I've eliminated the possibility of the engine bumping a bulkhead, and/or cockpit locker gear reacting to a harmonic.
Last weekend I discovered that when the boat is heeled to starboard (with the main up) the vibration stops completely. Straight up, it's back...heeled to port it's worse.
Any ideas?
Bill
Ganges #363
Engine Vibration
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Ganges #363
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bcooke
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- Boat Type: 1966 Pearson Triton
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Isolation mounts?
Alignment, bad prop or shaft installation (or something got 'bent' in the re-engine process), could be a bad motor to begin with.
I was thinking if the vibration goes away at certain angles of heel the engine may be shifting on its mounts a little bit. There could also be a weird hydrodynamic thing going on with how the water flows by the prop when the sails are carrying the load.
If it is that obvious then the installers mucked it up and should warantee their work. Let them deal with it. Its their problem.
50 hours in a few months. Wow, you are getting a lot of use out of that engine.
Alignment, bad prop or shaft installation (or something got 'bent' in the re-engine process), could be a bad motor to begin with.
I was thinking if the vibration goes away at certain angles of heel the engine may be shifting on its mounts a little bit. There could also be a weird hydrodynamic thing going on with how the water flows by the prop when the sails are carrying the load.
If it is that obvious then the installers mucked it up and should warantee their work. Let them deal with it. Its their problem.
50 hours in a few months. Wow, you are getting a lot of use out of that engine.
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Ganges #363
- Rough Carpentry Apprentice
- Posts: 55
- Joined: Mon Oct 15, 2007 10:59 pm
Engine Vibration
Thanks Britton, I've been thinking engine mounts, too.
The Hurst transmission section of the owners manual says there can be transmission vibration at low rpm, and suggests (in very small print) buying a cushioning part to eliminate that. But with the heeling difference, I think this problem goes beyond that.
I'm going to ask the installers to take a look at it, but thought I'd ask for some ideas here first. The engine runs great, I don't think it's a 'bad engine' problem.
Bill
Ganges #363
The Hurst transmission section of the owners manual says there can be transmission vibration at low rpm, and suggests (in very small print) buying a cushioning part to eliminate that. But with the heeling difference, I think this problem goes beyond that.
I'm going to ask the installers to take a look at it, but thought I'd ask for some ideas here first. The engine runs great, I don't think it's a 'bad engine' problem.
Bill
Ganges #363
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Zach
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I'd ponder loose mounting bolts on the starboard side. Or a stringer that is working loose...
On one tack they are under tension, the other they are slack... and at idle its bouncing around. Under load the engine will be trying to twist in the direction of its rotation, which might explain why it only does it at low rpms. Perhaps torque is pinning down the loose mount at higher speeds?
On one tack they are under tension, the other they are slack... and at idle its bouncing around. Under load the engine will be trying to twist in the direction of its rotation, which might explain why it only does it at low rpms. Perhaps torque is pinning down the loose mount at higher speeds?
1961 Pearson Triton
http://pylasteki.blogspot.com/
1942 Coast Guard Cutter - Rebuild
http://83footernoel.blogspot.com/
http://pylasteki.blogspot.com/
1942 Coast Guard Cutter - Rebuild
http://83footernoel.blogspot.com/