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3o Mercruiser Drive Throttle OK No Prop at Higher RPMs

farmall

New member
"I have a 1999 Bayliner 1754 F

"I have a 1999 Bayliner 1754 F/S with the Mercruiser 3.0 stern drive. Last night the kids and I were cruising along and we felt intermittent "surging" and lugging at about 3500 - 4000 RPM. I throttled down, then back up and the behavior was for the throttle to work but the prop was not keeping up. Only at lower speeds was I able to chug back to the boat ramp. Stern drive fluid was full, no leaks. No kinks anywhere in the throttle cables (boat is in very good condition, having not been used much when I bought it this year).
It does shift a little hard when first starting out, with some ratcheting only in forward until the clutch kicks in, but only when we first set out on a trip, then it goes away. My son mentioned that when the throttle is up and the prop is not keeping up, the water "tail" is crooked and the plume does not look right, like a blade was missing It is fine, and the prop is free and clear of debris and spins well in neutral. When this problem began last night, the only way it went forward was at low RPM's, and when I throttle up, the boat shudders and I have to back down and drive at low RPM’s. Reverse works fine.
I did notice a small chink in the forward blade portion above the propeller housing, with a small hole evident. Not sure if water gets in the prop shaft housing, and if so, if this means anything. Must have hit a small branch on the lake.
Whole thing is a mystery. I am not sure this is a cable problem, or something worse. Any ideas?"
 
Sounds like your prop bushing

Sounds like your prop bushing is slipping. I had the same problem a few months back. I could go no faster than trolling speed.
 
"does "surging and lugging

"does "surging and lugging" mean the engine is reving without changing boat speed? if so replace your prop, or have it re-hubbed at a prop shop."
 
"I pulled the prop, and checke

"I pulled the prop, and checked the whole assembly. No wear whatsoever on the shaft, the hub splines -- nothing. Even checked the drive fluid above, and the level was full, fluid clean and the bushings clean and not worn. I watched the shift cables and the throttle move appropriately on the engine as I moved the shift level into forward and reverse. Everything looks OK. Am I missing something?"
 
"David,
When my prop hub went


"David,
When my prop hub went it looked just fine. But in the water at high rev, the water resistance on the prop made the shaft spin inside the hub. I had my prop reworked and now it's fine."
 
"David, to check the prop hub

"David, to check the prop hub. Remove the prop and mark the prop and prop hub. reinstall and try it. If it is spining on the hub the marks will not match anymore. good luck"
 
"I adjusted the barrel nut on

"I adjusted the barrel nut on the upper arm of the shift assembly. Whether forward or reverse, the prop does not spin at all when rotated in the proper direction, instead of "clicking" when engaged prior to adjustment.

If this does not work while in the water, I'll let y'all know. Thanks again."
 
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