DT 37 Johnson water pump

[GARY SMITH]

I just got a DT37 Johnson running and now need help to fix the water pump. I’m not sure what comes apart to do the change. I don’t have a manual that goes back that far and I’d rather not take something off that I don’t have to.

[Buccaneer]

Here’s at 1940 version taken apart, should be very similar.
Getting the pump discharge line disconnect was the hardest part if I remember
correctly.
Sometimes the pump plunger wears out, the came on the prop shaft, springs
break, and the check balls can deteriorate, plug up, etc.

See attached manual below.

1939-40-Johnson-5-hp-LTATDT-Parts-Manual

Prepare to be boarded!

• This reply was modified 4 years, 5 months ago by Buccaneer.
• This reply was modified 4 years, 5 months ago by Buccaneer.
• This reply was modified 4 years, 5 months ago by Buccaneer.
• This reply was modified 4 years, 5 months ago by Buccaneer.

[Tubs]

If it doesn’t pump anything at all start with
looking for a stuck check ball.
Tubs

A "Boathouse Repair" is one thats done without having tools or the skills to do it properly.

• This reply was modified 4 years, 5 months ago by Tubs.
• This reply was modified 4 years, 5 months ago by Tubs.
• This reply was modified 4 years, 5 months ago by Tubs.
• This reply was modified 4 years, 5 months ago by Tubs.
• This reply was modified 4 years, 5 months ago by Tubs.

[GARY SMITH]

Thanks so much. I don’t usually work on stuff this old and have been putting it off so long I don’t even know where I got this one. I will dig into it today .

[GARY SMITH]

I took the pump apart and the small check ball was stuck so thanks for the tip. Now does the lower unit get marine grease and do I pack it in or just coat the gears and prop shaft ? I have to make a new gasket for the housing as I was a little over zealous taking it apart. Other than that it looks ok except for a pretty good wear mark on the back end of the prop shaft.

[Tubs]

Lubriplate 105 or John Deere Corn Head Grease

A "Boathouse Repair" is one thats done without having tools or the skills to do it properly.

• This reply was modified 4 years, 5 months ago by Tubs.
• This reply was modified 4 years, 5 months ago by Tubs.

[GARY SMITH]

ok thanks. I have a small tub of 105 that I had for the waterpump on my chris craft . Unfortunately that boat was pretty much destroyed in an accident on the road a mile from my house. I got the boat back but don’t have the heart to do it all over again after spending two years on it the first time. I hope to find a new home for it this fall.

[GARY SMITH]

My next issue. I’m thinking jb weld applied on the outside of the crack to seal it. Any other methods that you may have tried ?

[GARY SMITH]

Next issue is this broken ear. I’m thinking jb weld on the outside to seal the crack ? Any other methods you may have used ?

[nabmd]

JB Weld won’t hold it; when you tighten the screw it will pull the tab away from the rest of the casing. I’d get it welded by someone who does aluminum welding. JMHO, and similar experience. NABMD

[Author]

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