Pontoon Boat & Deck Boat Forum

Went to start getting THE FLOATER ready for the season. I knew I had dinged some stuff last season on the new to us lake. I've had the same prop for 11 years and it's time to replace. However I noticed some front to back slop it's about 1/4 of an inch. For those of you with your toons at home do you have any slop in yours? It may have always been there just never noticed..... Pics attached I didn't get pics of my big dings though.

Tolerances will vary by manufacturer but in general 1/4" is just fine and if the engine is in NEUTRAL. At that age, you may be due for a new thrust washer which reduces the play.

You may also want to try this....shift your engine into FORWARD (with the power off!!!). Slowly turn the prop clockwise and you should notice the prop move out and back. The overrun clutch is doing this as it is designed to handle deceleration (where the prop is turning faster than the engine - this allows for a gradual speed reduction).

BobL wrote: ↑

Thu May 20, 2021 9:12 am

Tolerances will vary by manufacturer but in general 1/4" is just fine and if the engine is in NEUTRAL. At that age, you may be due for a new thrust washer which reduces the play.

You may also want to try this....shift your engine into FORWARD (with the power off!!!). Slowly turn the prop clockwise and you should notice the prop move out and back. The overrun clutch is doing this as it is designed to handle deceleration (where the prop is turning faster than the engine - this allows for a gradual speed reduction).

Good info, thanks! I will check that on mine.

Thanks Bob!!!!!!!! Forgot about the thrush washer!

curtiscapk wrote: ↑

Thu May 20, 2021 1:56 pm

Thanks Bob!!!!!!!! Forgot about the thrush washer!

I'm having the same issue with mine, which I only noticed when I started exploring why it would pop out of forward gear when I gave it more than 40-50% throttle. Both gears and the clutch dog look like new still, and all the bearings are in good working order. Haven't been able to figure it out yet... As for the thrust washer, it sits at the end of the splines on the shaft, but my "slop" or "end-play" is because of the gap between where the thrust washer sits and the seal for the bearing at the back of the carrier. Parts diagrams don't show any parts on this shaft that I don't already have, so I'm not sure what is causing my issue.

Also, I noticed that if I moved the gear selector from Neutral towards Forward JUST enough to where I can't turn the prop counterclockwise without it turning the motor over, if I push the prop in that 1/4" of slop, it disengages forward gear and I can spin it freely. So when on the water under power, the prop is pushing the water backwards and thus pushing itself forward, thereby reenacting my 'bench test' of disengaging from the forward gear. At least that is the only diagnosis I'm left with at this point in time...

Well, at least you won’t be needing a torch to get the prop off. On a previous boat I owned, which was used exclusively in brackish water, the original owner told me he always left the prop loose enough to provide just a bit of play so it wouldn’t freeze up on the shaft. I continued to keep it adjusted like that. No I’ll effects as long as the thrust washer Wes in good shape.
That engine Lapp was a 1973 Johnson 115 hp. I replaced it in 1997 or there abouts. Still had the original lower unit with no rebuilds on it.