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1967 Johnson 3 Hp water pump won't work

H

hunerdp

New member
Hello,

This is my first engine restore and first time posting on this forum. I got a Johnson model JHF-21 that I got to run wonderfully....except it's overheating almost instantly. There's just a little bit of water vapor coming out of the holes in the lower unit....not an expert but seems like there should be more.

So I decided a good first step would be to see if the water pump is working. I took off the lower unit and used a drill to turn the crankshaft (I saw some youtube clips of people doing this...seems like a legit way to test) no water came up. Okay I thought....well let's see if water is even reaching the impeller. I took out the impeller out as well as the wear plate and the water still didn't reach the level to where the impeller would be even when the crankshaft was rotating pretty quickly.

I feel like I'm missing something. At one point I did take the driveshaft completely out of the gearbox....I think I might have read that's kind of a no-no and I might need to line things up in the gearcase again? I'm a little stumped and can't find much on the internet...that's why I'm here haha.
 
The driveshaft slips right back into the pinion gear.-----New factory impeller installed?-----With a new impeller it is almost impossible for the pump not to work.----And in your test bucket was water 6 or 8" above the impeller
 
Okay easy fix....didn't realize the water had to literately be at the level of the impeller. Problem solved!....For now...will try starting the motor in a barrel tomorrow.
 
Note Racer said 6 or 8” inches ABOVE the impeller.
These are not self priming, you need water ABOVE the impeller, not just at the impeller.
 
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