Chrysler 75 hp 1975 Spacer plate?

[ErSa]

Hello Chrysler experts,

I have changed spacer plate in my motor from #404680-2 to #692 680.
One deiference is that there is an extra hole in the waterinlet passage.
1. What is the function of that hole?
2. Shall it be plugged with a screv so it does not steal water from the cooling system?
Beside that the plates seems to bee compatible.

Happy New Year / Erik

 

[topgun3690]

Wondering why you needed to change the spacer plate.....cracked, broken? Looked at a few on ebay......the pics show some with the hole and some without.....same part number. Hard to tell from the pics....is that a blind hole or does it go into the water passage?
On another note, when mounting the spacer plate be sure you can install the towershaft. On mine it had to be inserted into the spacer plate before installing....not enough clearance to slip it in there....at least on mine.
If nobody responds with a good answer about the hole, you might give Franz marine a call and ask him.
Happy New Year!

 

[jerryjerry05]

Probably won't help to plug it or leave it alone.

 

[ErSa]

Probably won't help to plug it or leave it alone.

Thanks for your theories. My theory, so far: The Force do not have a water bypass valve so if the pressure becomes too high the water can escape throught this "extra hole".

 

[jerryjerry05]

1988/89 Force did away with the pressure relief/ poppet valve.
They found it would get stuck real easy and in salt water became useless real fast.
It was located on the bottom of the block.
Diamond shaped cover with 2 TINY screws holding it in place.
They moved the pressure relief up in the thermostat housing.
They added a spring at the thermo itself, pressure gets high the thermo gets pushed out of the way, releasing the pressure.

 

[ErSa]

1988/89 Force did away with the pressure relief/ poppet valve.
They found it would get stuck real easy and in salt water became useless real fast.
It was located on the bottom of the block.
Diamond shaped cover with 2 TINY screws holding it in place.
They moved the pressure relief up in the thermostat housing.
They added a spring at the thermo itself, pressure gets high the thermo gets pushed out of the way, releasing the pressure.

Thank you for the story of the poppet valve in Force. I will put a screw in my "extra hole" to get more flow through the cooling system in my Chrysler, with old type of poppet valve.

 

[jerryjerry05]

IF?? the pump is in good shape? it should pump enough water to cool 3 motors.
Start it without the thermostat in and see how much water it pumps.