Trojan Boat Forum

Headed out for a test hit on the water and didn't get halfway out of the slip and the port side prop shaft slipped out of the yoke on the v-drive. Kind of like getting a flat tire in your driveway the location was the only bright side to the situation, that and no apparent damage. My son went into the water and I went into the engine room and we managed to get it pushed back I and tightened down.

While I was there I thought I better check on the starboard shaft and make sure it was tight. I put about a half turn on it with a break over bar and called it good. We continued out and everything went fine.

Last Sunday the port side slipped out again, this time in the middle of the lake not in the slip. So we limped in on one leg and talk about fun backing into the slip. The whole marina had a good time watching the newbie try to park his new (to me) boat. Actually, everyone nearby was very helpful (mainly so I wouldn't ram their boats) and I could not have put it in without there help. Thanks again.

Anyway, I noticed that the yoke on the starboard side had a hexbolt and lock nut which the port side did not. The port side had a square head bolt and no locking nut, I plan to correct that now. I also plan to use Loctite, is there anything else that anyone would suggest to prevent this from happening again?

The square head bolts are the norm in the shaft coupler . The they are normally safety wired to keep from coming lose . first the shaft should be a very tight fit into the coupler almost a press fit , if not its most likely worn . The shaft could be worn also . Make sure you get the shaft in all the way in the coupler . The fact that the starboard side has hex bolts and lock nuts makes me believe it also had issues . While you maybe able to get by with you fix New couplers may be needed . If you replace them I would go with the split type . cost more but hold the shaft better ( that's what I have ) One other thing NO SS Bolts !

Thanks for the reply Prowler I think I will get the split couplings to be on the safe side. It looks like that would be easier to insert the shaft and make sure it is all the way in, then crank it down tight. When we inserted the shaft the last time it definitely was not close to a press fit.

I replaced the old coupler with a new split type coupler and there was a huge difference in the fit. The old coupler was quite worn and would slip on and off with ease, while getting the new one on was quite a chore. I finally got the shaft and coupler lined up perfectly and it took several blows with a hammer in the confined space to get it all the way on. Then I used Blue Loctite on the bolts and an impact to make sure it was tight. I painted both shafts where they enter the coupling with a little white paint so I can monitor them for slippage.

Good deal ! You put the key in right ? (sorry but had to ask lol) you should in good shape .

Yep, I even put the key in. Thanks again for suggesting the split coupling. That thing is on good and tight.

Lance F28 wrote:Yep, I even put the key in. Thanks again for suggesting the split coupling. That thing is on good and tight.

Only way to go IMO , recheck bolts after a while of running in case something seats in . Good to be safe and in my case in case I forgot something