Is it feasible to straighten a prop shaft?

[Jeff J]

The title says it all. Brand new lower unit in July that a renter bent the shaft on in September. Have had the lower unit disassembled and sitting on the bench ever since waiting for a shaft that I can’t even get a status on.

Stainless prop doesn’t show any impact damage. I have seen some really bad stainless prop damage without bent shafts so I suspect the renter was using the motor as an anchor at the beach.

 

[racerone]

What motor ?------Was boat on a trailer ?----What boat ?----Did renter put a new prop on ?----Was it bent before this last renter used it ?

 

[Jeff J]

2017 Suzuki DF200A mounted on a 2017 Crest tri-toon. Definitely happened in the water. I am the only one who has trailered that boat all year. I pulled it out this time for general servicing. As soon as I put it in reverse to back out of the slip I knew something was bent. Boats shouldn’t shake like that (which also means one or more of the deckhands should have been fired for not catching it because they don’t let renters park the boats).

 

[Scott Danforth]

With a dial indicator and shop full of tools and years experience, you probably can get it straight.

 

[Scott06]

A pair of V blocks, press, and dial indicator yes you can do it if you have some experience. You really have nothing to loose trying, or if you have a machine shop local they may have some experience doing this

 

[dwco5051]

Yes, like the other posters said. Not a job for a do-it-your-selfer with a piece of rail for an anvil and a 32 oz ball peen hammer. Any decent machine shop can do it.

 

[Jeff J]

I may take a stab at it. I have a press and a dial indicator. I can easily make the V-blocks out of steel or wood. I can’t think of a better way to get experience and the owner knows the situation with getting a new shaft.

I could actually practice on the one from the old lower unit. It hit a log floating just below the surface of the water at about 40 mph and is sitting next to the boat. The bend is worse on it (the skeg was gone, prop trashed and housing cracked too). They were good renters. They actually came back and were up front about hitting something. Usually things were left unmentioned and when confronted about damage the answer was “wasn’t me” when the culprit could be positively identified. I changed at least 15 props last season and had to get 5 out of 7 pontoon boats welded on, one of them twice.

 

[JimS123]

Had a similar problem. The certified dealer said it was OK. It wasn't. Had another certified dealer straighten the shaft. It wasn't. Continued with issues and finally replaced the shaft with a new one. Problem solved.

 

[Jeff J]

Don’t get me wrong. My preference by far is to replace it but it’s coming up on 6 months waiting for the order to come in with no updates on the status from Suzuki. I had the lower unit for that boat on order for a month before I was able to source a replacement from another dealer 300 miles away. I suspect they pulled it off a new motor for me. I have had a VST on order for the DF250 since June 2021.

 

[Scott06]

Don’t get me wrong. My preference by far is to replace it but it’s coming up on 6 months waiting for the order to come in with no updates on the status from Suzuki. I had the lower unit for that boat on order for a month before I was able to source a replacement from another dealer 300 miles away. I suspect they pulled it off a new motor for me. I have had a VST on order for the DF250 since June 2021.

Send it to a place like this

Propeller Inboard Shaft Straightening and Shaft Repair - H&H Propeller

H&H Propeller Inboard Shaft Straightening and Shaft Repair

www.hhprop.com

 

[dwco5051]

Since you already have a junk bent shaft laying around go ahead and play with that one. If you can get it to within .004" runout then try to do the one you want fixed. You have nothing to lose except for the time spent learning a new skill.

 

[vroom ZOOM]

had the shaft on my df200 straightened by a prop shop after the motor fell off the transom