Replacing prop hub

I replaced the hub on a 4 blade Quicksilver prop on a F150 Yamaha. When I tightened the castle nut I couldn’t get the nut tight enough to use the cotter pin that came with it. The bottom of the slot on the castle nut wasn’t to the bottom of the hole in the shaft. I had to use the next size smaller pin. It’s the same thrust washer and I tried both the outer washer that came with the hub and the one that had been on it with the old hub but neither one worked with the cotter pin that came with it. I know if I could turn the nut another 1/8 of a turn everything would fit fine, but there’s no way that’s happening. In 3 hours of fishing I probably ran the motor a 1/2 hour with no problems. I’ve changed hubs a few times but this is the 1st time I’ve ever had a problem getting the hole on the shaft to line up with slot in the castle nut.

Pat K wrote:

I’ve changed hubs a few times but this is the 1st time I’ve ever had a problem getting the hole on the shaft to line up with slot in the castle nut.

Obviously something is not right. Did you disassemble everything and reassemble when you realized there was an issue? The new hub/washers stack up, should be the same length as what it is replacing. If it’s not, either you have a wrong part or a part is installed incorrectly.

I disassembled and reassembled it several times. It’s a genuine Quicksilver part with the same part # as the original. It all looks the same as the original, I just can’t turn the nut 1/8 more of a turn to get the right size cotter pin to work. I tried again after running the motor and the result is the same.
There was no vibration or odd sounds coming from the lower unit when I ran it.

Is the thrust washer ahead of the hub, installed correctly? (facing the right direction, not flipped 180)

I didn’t remove the thrust washer. If it was backwards, the taper on the shaft not matching the taper on the washer would push the prop back a lot more than 1/8 of a turn on the nut.
I took off the prop, pressed out the old hub, pressed the new hub in then put the prop back on with the pieces in the same order they came off. A few minutes ago I watched a YouTube video that installed it the way I did only their cotter pin worked. I’ll probably return the hub kit for a new one.

This morning I called the shop that has done work on my motor. The owner told me they’ve run into this a couple times in the last year. The flange on the end of the splined metal insert is slightly thicker than it should be. A quality control issue that he said they are blaming on COVID just like every other mistake in the past 2 years. I didn’t buy the hub kit from him, but he told me to bring in the splined piece and he’ll trade it out.

Did you install the Thrust Washer backwards?

robby wrote:

Did you install the Thrust Washer backwards?

The thrust washer is on the right way. I just reassembled it with the new splined insert and now the larger cotter pin fits.

Pat K wrote:

The flange on the end of the splined metal insert is slightly thicker than it should be.

This contradicts what you told us earlier.

Pat K wrote:

It all looks the same as the original,

Therefore I stand by my original statement.

Huntindave wrote:

Obviously something is not right.

Good to know it is being taken care of.

Huntindave wrote:

<div class=”d4p-bbt-quote-title”>Pat K wrote:</div>
The flange on the end of the splined metal insert is slightly thicker than it should be.

This contradicts what you told us earlier.

Sorry if I misspoke. I appreciate your comments, it helped me sort through it and decide what to do.
The difference was not enough to see unless you used a micrometer or have much better depth perception than me.
It would have worked with the smaller key but it’s a piece of mind thing to have it fit right.