1970 Johnson 60 HP leg

[Richmond2000]

I have a 1970 60 HP Johnson with a broken skeg and bought a MINTY 72 65 HP without power head
both ore the electro hydraulic shift
my 70 has 32 water pipes from the impeller pump up and the 72 has only ONE
I plan on using my 60 HP power head on the complete 72 - will it work?

 

[F_R]

That's a good question, and I'm not sure I know the answer. But I can explain the water tubes. Your 1970 has a thermostat controlled recirculating cooling system. When the thermostat is closed, the water returns to the water pump through the second tube. Then it is sent back for another pass through the powerhead. This continues till the powerhead is at optimal temperature, then the thermostat opens and some water is discharged and replaced with cool lake water. It is not an either-or situation. The thermostat is constantly sampling the temp and opening and/or closing as necessary to maintain correct temperature. But the single water tube system is very different in that water is not returned to the pump. It merely samples the temperature and modifies the flow through the block and then to discharge. So....obviously the cooling system paths are different in the powerhead as well as the powerhead adapter and tubes. What I don't know is if enough stuff can be swapped to make the changeover. I'm thinking not.

 

[racerone]

Put the entire pump from the 70 model onto the 72 model lower unit.

 

[Richmond2000]

Put the entire pump from the 70 model onto the 72 model lower unit.

as in BOTH tubes and EXHAUST adapter (plate power head mounts to)?

 

[Richmond2000]

That's a good question, and I'm not sure I know the answer. But I can explain the water tubes. Your 1970 has a thermostat controlled recirculating cooling system. When the thermostat is closed, the water returns to the water pump through the second tube. Then it is sent back for another pass through the powerhead. This continues till the powerhead is at optimal temperature, then the thermostat opens and some water is discharged and replaced with cool lake water. It is not an either-or situation. The thermostat is constantly sampling the temp and opening and/or closing as necessary to maintain correct temperature. But the single water tube system is very different in that water is not returned to the pump. It merely samples the temperature and modifies the flow through the block and then to discharge. So....obviously the cooling system paths are different in the powerhead as well as the powerhead adapter and tubes. What I don't know is if enough stuff can be swapped to make the changeover. I'm thinking not.

the T stat you are referring to is in the head of the engine correct? I ask as I also got the T stat cover off the 72 a and it looks to fir my 70 as I do NOT have a T STAT OR EVEN the the cover as the previous owner replaced it with a blanking plate