Stuck lower unit on 1986 125 force

[ggou812]

I am attempting to change the water pump on my 1986 125 force motor,
(1251x6b),
and have removed the 7 bolts and the shift linkage pin. Seems to have come down just enough to see that the lower housing is free and not corroded to the upper half, and I have just enough of a crack to see that it did come down slightly, but now refuses to go further even with trying moderate tapping to the lu area. is it possible that the power shaft is frozen to the engine at the upper half? I have read that you reassemble with antiseize to the splines, but I have not had this motor in use before, purchased it used from an old friend and not sure if it the water pump has ever been changed until now, so possibly its going to give me grief coming off. This motor runs well, but has sat for 4 years and needs a little tlc before i test it in the water. Any ideas on what might help the shaft to break loose from the splines would be greatly appreciated. ona second question, Is the temperature sensor on the head (orange wire) on this motor a simple buzzer switch? if so, I may need to find a temp sending unit for my teleflex 50-200 Fairenhiet temp gauge, as the buzzer sending unit can't be complatible with my existing gauge.

 

[Frank Acampora]

Re: Stuck lower unit on 1986 125 force

Since the load on the shaft is downward while running, there is some free play upward when not under load. THUS: when the drive shaft is stuck in the crankshaft snout, you should be able to drop the lower unit only about a 32nd inch or less.

You did say seven bolts--I take it that means you did remove the exhaust snout and the hidden bolt inside the lower.

The factory approved method for unsticking a driveshaft is to replace one or two of the bolts with some clearance left, then start the engine and rock the lower unit a bit. While pulling down. Sounds BRUTAL, I see potential for damaged fingers, hands, and arms, and I would only try it as a last resort.

The sensor in the head is usually just an open switch that closes with excess heat. However: If the sensor is on top of the head and screwed in with a wire attached on top, it could be a variable sensor. If this is the case, check it with an ohm meter as the engine heats. Resistance will lower with added heat.

 

[ggou812]

Re: Stuck lower unit on 1986 125 force

Yes, I did remove the snout and hidden bolt, and is about a 32nd inch it came down. I will try starting the engine with 2 bolts in. I assume the idea is to let it drop slightly but not too much with the added vibration of running? Also would think that this is to be done in nuetral, I will remove the prop as a precaution anyways, as I may need my fingers for the reassembling. As far as the sensor goes, it goes from completely cold to topping out with no in between reading on my gauge, so its apparently just an open/ close switch, and it is held in the top of head by a rubber plug and an o ring with no threads. The fact that it activates at all could possibly be that it IS overheating somewhat, thus the pump change is needed anyway.The trick will be to find a compatible sending unit for the gauge, or may have to replace the entire gauge with a new kit. Thanks for the tip, will let you know how it turns out.

 

[ggou812]

Re: Stuck lower unit on 1986 125 force

Using 2 loose bolts, I got the lu to come loose by simple turning over a few times without having to start the engine. Pump housing and impeller look original or at least very worn, so getting a new complete kit. Thanks for the tip!