Mercury 80hp Stalls and locks in reverse

[TRColT]

Hi
I have a Mercury 80Hp Thunderbolt (1978 or 1979)
Everything runs great when I shift to foward, but I can't get it to reverse without killing and locking the engine.
When I put it in reverse, the propeller start to spin a little then the engine dies. The shift cable can't move anymore (foward or neutral) It is stuck there. The engine won't crank with the starter either. I need to go to the propeller and spin it by hand until it makes a "clic" and get back to neutral.

When I try it on the trailer with the muff, it shifts easily foward and reverse. When I get the boat to the water, the problem happen.
I've dropped the lower unit and spins the input shaft by hand while moving the shift arm. Once again, everything is fine.

It also shifts to reverse if I put the fast idle lever up to about 1200 RPM, but it's way to high for a smooth engagement.

Anyone ever encounter this problem?

Thanks

 

[jimmbo]

Any chance you have the shift and throttle cables mixed up?

 

[GA_Boater]

Any chance you have the shift and throttle cables mixed up?

Yeah - If the warmup lever shifts the motor, the remote has some serious issues or the cables are reversed or the lower unit was installed with the shift shaft out of sync.

Starting with the easy stuff - Have someone shift the remote as you look at the cables on the motor. In neutral shifting into forward, the shift cable on the bottom should move before the throttle cable.

 

[TRColT]

I don’t think the cable are mixed up.
The warm up lever doesn’t shift the motor. Maybe my last sentence was not clear. I meant I can shift the motor to reverse if it rev at 1200rpm (by lifting the warm up lever)

 

[TRColT]

Anyone else? I spent another 2 hours today trying to figure it out. I tried multiple adjustement on the shifter cable, but still don't get it. It still dies in reverse.

Another information that might help. When I move the slider to reverse with no cable attached, I feels like i'm pushing on a spring before it engages. It might be normal, but I don't get the same feeling on foward.