Thread: bent shaft
View Single Post
  #1   IP: 24.53.89.131
Old 06-06-2018, 05:21 PM
Peter's Avatar
Peter Peter is offline
Afourian MVP
 
Join Date: Jul 2016
Location: Nova Scotia, Canada
Posts: 297
Thanks: 162
Thanked 140 Times in 101 Posts
bent shaft

Hello all,

Looking for some advice. Late last season I noticed I had an oil leak at the back of the reversing gear and a rather unpleasant sound when the boat was put in gear. Also had a dripping water pump.

This spring I hoisted the motor up into the salon and performed the repairs - replaced rear seal, replaced thrust bearing and rebuilt water pump. The old thrust bearing was a little gritty feeling and the spring on the oil seal was broken.

The MOYER tech tip video on the rear seal replacement was excellent and made the job go very smoothly. I also installed new motor mounts.

Put engine back onto the mounts, did an alignment (which was a dream with the new mounts) and all seemed to go well.

Today was launch day. Engine started right up, no oil leaks and no dripping water pump. Popped it into gear and no unpleasant sound. The old thrust bearing was a little gritty feeling.

However, a bit of a shudder when I applied some throttle. Go the boat to my slip and went below to see what was up.

Shaft coupling is nicely mated to the output coupling on the engine and no wobble there. But, the shaft was wobbling in the stuffing box... There was no vibration last season. The video below shows how much wobble there is.

https://youtu.be/PjvFHR7Ea7E

(Apologies - I tried to embed the video following Bill's instructions found here - http://www.moyermarineforum.com/foru...67&postcount=1 but no luck.)

I have two theories about how the shaft came to be bent.

1) We could not get the shaft coupling off the output coupling and we broke it free when we lifted the engine. In retrospect we should have tried harder by tapping on the prop close to the shaft.
2) I installed a new zinc and my yard guy told me to hammer it on to make sure it was well seated. The hammering did indeed allow me to get more turns on the zinc bolts but maybe induced the bend?

I have a 3/4" shaft and I think it is perhaps bronze?

Questions:

1) Can I live with this for this season or will I be buggering something up - cutlass bearing? My motor usage is motoring in and out of the harbour - 10 minutes tops each way.

2) If the answer is no, and we assume the damage was done when the engine was lifted, what about rotating the shaft until the high point is up and trying to "tap" the shaft down with a largish hammer?

Looking forward to your wise council!

Thanks,

Peter

PS - boat is a 1976 Ericson 29

Last edited by Peter; 06-06-2018 at 05:42 PM. Reason: spelling
Reply With Quote