My 82 Mercury 40hp is causing me grief

1) I get boat back from shop, bracket had crimped cable in control box

2) I put boat in water this morning. Starts fine, shift into reverse fine, back away from dock

3) Shift forward, no problem, cruise over to spot 1 at no wake speed

4) Fish, move, no problem

5) Fish, move, shift forward and open it up full for a bit, no problem

6) Fish, go to move, PROBLEM!! Motor starts fine, stalls when shifting forward(and reverse)

7) Finally get motor to shift without stalling, but sounds like running to high at half throttle, Move to full throttle, sounds good and moves

8) Go to leave last spot, motor starts, stalls on shift, won't turn over any more (no way battery should have been mush, but all I get is click)

9) Trolling motor to dock

I recently had new(used) control box installed. I'm hoping just linkage cables

Verify that you did not pick up anything on the prop, e.g. fishing line, cord, plastic, etc..
Tim

Was this a low bid shop? Just kidding, I hope.

Seems like linkage problem and related wiring problem for ignition in control box, maybe? Seems like new problem would be related to recent work.

I had a used 1996 40 hp Mercury installed on my fiberglass boat last year by a boat shop which is not really close to me, but have had very good luck with advise and service from them. It wasn't cheap but have had no issues with the motor since it was installed.

Good luck.

Cables and linkages turned out to be fine. Electric was also good.

Turns out the water pump was bad. Water was coming through, but not enough.

Motor was severely overheating and shutting down for its own good.

I would avoid a shop that returns a motor to its owner with a bad impeller. It's the most common and important maintainance issue on a motor, and they over look it?