Bent Prop Shaft

[willwork4fish]

Buddy of mine noticed his prop shaft looked a little off when he was putting on a new prop to try. He put a travel gauge on it and found a high spot of 0.025" which seems doesn't seem like a lot but after looking it up seems like about 3X more than would be acceptable. He doesn't remember hitting anything this year, said he ran up on some sand last spring. Motor hasn't been vibrating at all and lower unit lube didn't have any water in it.

Has anyone tried the method of straightening it with a jack? Motor is a '08 175 HPDI. thanks

[PJ-Rohlf]

I have seen people use a piece of pipe and some wood blocks under the skeg. This may work in an emergency situation to get by but I would take it to a shop and have them send it somewhere they know will get it straightened properly. Especially if the boat is getting put up for winter and he doesn't need it for a bit

[MCIPinkie]

I'd take a 2 x 4 for a softener and give it a judicious whack with a hammer.

If not, I'd try one of the jack methods.

In reality, I'd go fishing.

[06 SB]

I am not sure how much bend it takes but it can compromise the seals and let water into the LU. I would at the very least do a pressure AND vacuum test before using it again.

[getfished]

Take it to a shop. Let them pull the shaft, straighten it and reinstall it. couple hundred bucks done right.

[billnorman1]

Put the prop on. Spin it. There should be a dimple in the middle of the end of the prop shaft. If you see the edge of the prop wobble or you can detect the dimple moving out of perfect line when the prop is spun, there is something wrong. I wouldn't hit anything on my lower unit with a hammer.

[21XDC]

I believe tolerance for Yamaha prop shaft is 7000ths. Since the human hair is about 3000ths I’m not sure anybody could accurately straighten the shaft by hand.

[ssmithboats]

trying to straighten a prop shaft with a hammer an wood will damage your seals just take it to someone an have them pull it apart an a good machine shop can straighten it back to specs an be sure to change shaft seals.

[JJohnSind]

I recently tried this using “YouTube” instructions. Don’t bother, it’s not easy to do and you could break something trying. Start working on getting your replacement prop shaft. They are scarce and it took 2 months to get mine.

[djb750]

The seals are gonna give long before the prop shaft. Same with the aluminum casting. Not a good idea. The case isn't designed to take a load perpendicular to the drive shaft - at least not a load anywhere close to what it'll take to "bend it back straight".

If it's important to you, get it rebuilt.

[Commanchejoe]

Not to mention all the stress you put on the transom trying to do that