1989 supra ts6m shaft.

[elknof3]

Hi everyone!
I got a broken shaft yesterday on my trip to the lake. I really don't know much information as to where to buy stuff for my boat sisnce I live in Mexico and most of the time I get my parts done at the local lathe shop. It has happened to me before, the original one broke a couple months ago and this new one didn't last much. I guess they really don't know which materials to use, this shaft broke in two parts, the coupling kept one of the sides and the other side stayed attached to the propeller so I think the material of the shaft might have been a little too stiff. My options would be to either find out which is the correct material to use or to find the new parts and buy them.(shaft and coupling). I hope someone can help me please as it really saddens me not to have my boat reaready ;)

[michael hunter]

General Propeller Bradenton FL. (941) 748-1527 I got a new shaft for my 92 Comp for 260.00. Send them the old shaft and they will make a new one.

[chris young]

This is my usual post, perhaps it should be a sticky? If you are breaking shafts, especially if the break is at the keyway, then at the coupler end, the coupler is probably loose on the shaft, and at the prop end the prop is probably not properly lap fitted. This is often the cause for shaft breakage, as the coupler or the prop bangs against the key and causes the shaft to crack at that stress point. When you replace your shaft, it is recommended that you also replace the coupler and you really must lap fit the prop.

Good luck.

[michael hunter]

Chris can you expand on your procedure for lapping a prop?

[SquamInboards]

This is my go-to prop lapping reference video:

https://www.youtube.com/watch?v=2ozh4JjoWm4

[chris young]

Yup, mine as well. When I did mine, I did it also with the shaft out of the boat, made a little adapter so I could put a drill one the coupling end. I was doing it by spinning the prop on the shaft by hand, but it was taking forever. If I was going to lap it on the boat I'd build something to spin the prop with a drill.

I do believe everyone should watch the whole video because he addresses all the issues. I think fitting the key and making sure the prop is seating on the shaft the same depth with or without the key is one thing that a lot of people may skip over, and all the lapping in the world won't work properly if the key is keeping the prop from seating. As I've posted numerous times in the past I lost my prop due to improper lapping. I was very fortunate that the shaft didn't crack(I did a die penetrant check at both keyways while the shaft was out) as for a while I'm sure the prop was banging against the key. I also went the extra bit and heated the prop in a 200 deg oven before I put it on the boat. With that extra step I think I could probably run the boat even with both of the nuts missing LOL. (which btw is how I lost my prop)