Stalling issue mercruiser 5.0 v8

[nkraz]

Ok, alpha one gen 2. Everything ran fine last year, this year before getting it in the water I replaced the impeller.

Everything runs great on muffs in the driveway, but got it on the water and unless I'm giving it a lot of throttle it stalls. If I am going relatively straight and at a higher throttle it seems to run ok, but I turn or lower throttle and it stalls. Definitely added resistance to the prop seems to stall it.

What I did when replacing impeller:
I removed the upper and lower unit, so I could work on it in the garage. Replaced all seals etc, all went fine, so I thought. The one thing I didn't do that I am now reading is that I did not bungee my prop in "drive" while reinserting sterndrive. Everything went together easily and lower unit drive shifter is in the groove it is supposed to be. Is it possible that I am off by a spline or so when I reinserted the sterndrive and it's causing this issue, or is it more likely something else is going on?

Thanks for any insights.

 

[Rick Stephens]

If you missed the timing on the shift shafts when you mated upper and lower it wouldn't shift into gear. That won't cause it to stall when you are in gear. Look to your motor and carburetor, not your drive.

 

[nkraz]

If you missed the timing on the shift shafts when you mated upper and lower it wouldn't shift into gear. That won't cause it to stall when you are in gear. Look to your motor and carburetor, not your drive.

Carburetor was rebuilt almost exactly a year ago and was running fine all last season. Sounds perfect in driveway, but in the water it sounds like gear crunching and obvious stall issue coming from the area where the sterndrive mates with the engine. If I put it in gear while on muffs, I don't get any odd noises or issues. I haven't taken it off yet to see if there is anything obvious, yet, but that's next step.

Shift interrupt seems to be getting engaged when on the water, but if I give it enough throttle and don't turn the boat, it will run ok.