Stiff prop shaft

[bobk]

One last question guys. My boat has three cutless bearings per shaft and a dripless packing gland. The prop is VERY hard to turn by hand suggesting I'm wasting fuel. My diver tells me the other Hatts in the basin take much less effort to spin the wheels while in the water. I've probably put 800 hours on her this way, and the PO probably had even more. I don't see any issues like hot cutless etc. Should I be concerned, and if so where should I look.

Bob

 

[SKYCHENEY]

Does the clutch drag at all? Do the shafts spin some cold at idle while in neutral? You may not have tight cutlass bearings at all, just transmissions with tired springs on the clutch packs.

 

[garyd]

This could be the cause.

 

[mike]

Check the alignment at the transmission coupling. The engine may be out of alignment in relationship to the centerline of the propshaft.

 

[Brian Degulis]

This could be the cause.

I think your right Garyd I had no stiffiness at all until I read your post


As for the boat I would look at alignment not only the engine alignment but the bearing to bearing alignment.

Brian

 

[LENZ]

I think your right Garyd I had no stiffiness at all until I read your post


As for the boat I would look at alignment not only the engine alignment but the bearing to bearing alignment.

Brian

Second that!

Lenz

 

[REBrueckner]

Bobk...above posts are good advice. maybe somebody used a wrong size cutlass bearing....

Any vibration?....

A good way to start is to disconnect the shaft coupling from the transmission coupling and see if the shaft when disconnected turns much more easily than when connected ....this can be done in the water...if you are uncertain, disconnect the other engine shaft and compare twist resistance....

Several years ago I noted my port shaft was more difficult to turn than my starboard; yet when I checked it again at the end of that season, it was fine...never did figure that out....maybe rope/cord wrapped around/in a cutlass....

 

[Captned]

Funny, cuda's usually dont do that to me.....

Captned
MBMM

 

[bobk]

Does the clutch drag at all? Do the shafts spin some cold at idle while in neutral? You may not have tight cutlass bearings at all, just transmissions with tired springs on the clutch packs.

Both shafts are equally hard to turn. Sky, I don't understand the spring issue, but if the shafts can be turned reasonably easy when disconnected, do I need to get into the transmissions? I'll check to see if the shafts turn at idle/neutral this weekend.

Bob

 

[SKYCHENEY]

Both shafts are equally hard to turn. Sky, I don't understand the spring issue, but if the shafts can be turned reasonably easy when disconnected, do I need to get into the transmissions? I'll check to see if the shafts turn at idle/neutral this weekend.

Bob

If the shafts turn easily when detached from the trans, then you may have an alignment issue. If the alignment checks out, then the resistance is within the transmission. I had this problem with my Allisons. One of them would drag while idling in neutral. Upon disassembly we found the 8 (I think) springs that release the clutch plate were compressed and needed replacement. Once we put the new springs in, we no longer had shafts that spun while idling in neutral and they were much easier to spin by hand with the engines shut off.

 

[bobk]

Sky, how big a job is it to get to the springs and what are the consequences of ignoring them? I don't think my props are spinning in neutral or I'd have seen strain on the dock lines when warming the ponys up.

Bob

 

[Boatsb]

Do the tranny couplings spin easy on their own?

 

[SKYCHENEY]

Sky, how big a job is it to get to the springs and what are the consequences of ignoring them? I don't think my props are spinning in neutral or I'd have seen strain on the dock lines when warming the ponys up.

Bob

It's not an easy job. You have to detach the trans from the engine and pull it back to get the clutch packs out. It doesn't cause any problem to have the clutch dragging a little while in neutral. It's really only a problem after it gets so bad that the boat is still moving while in neutral. Mine was annoying and I had to change them as I couldn't ever even leave the helm to grab a spring line.

If your shafts turn free while disconnected and your alignment is good, then I wouldn't worry about looking any further.