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1966 20 HP Johnson Not Pumping Water Help Please

S

skeet

New member
"I am a first time boat owner,

"I am a first time boat owner, I have a 1966 20 HP Johnson Model # FD-20C. I finally got the motor started, but noticed no water was being pumped out of the motor. I just replaced the impeller and water tube grommet, but I am still not seeing any water coming out of the lower unit and the motor dies. Am I missing a gasket under the impeller plate or some other gasket or seal. I don't see any reference in the Seloc manual for this motor. Can anyone please shed some light to a complete rookie? Thanks"
 
"I'd suggest that you drop

"I'd suggest that you drop the lower unit to double check your work.

Use Boat Armor Sealer 1000, available at any reliable auto parts store, to seal the plate to the lower unit (no gasket there), and also to seal the impeller housing to the plate. Make sure that the pin is engaging the impeller properly and also that the water tube is actually sliding within the impeller housing grommet. It is easy to hit the top side of that grommet which will fold it over somewhat.

The water must be above the water pump area. This is logical but at times it does get overlooked.

Check the compression. If a head gasket is failing, it's possible for the combustion mixture to enter the water passageways which would cause a stalemate..... water would encounter the combustion pressure and would not be able to travel any further.

Let us know what you find.

http://stores.ebay.com/Evinrude-Johnson-Outboard-Parts-etc"
 
"Thanks Joe, I will try the se

"Thanks Joe, I will try the sealer on the impeller plate and housing. This is one step I did not do. I had the motor running last weekend and it was pumping a little water, but not a steady stream, this is what lead me to beleive I needed a new impeller. Now it is not pumping any water. While I had the unit off I checked all the gears, and replaced all bearings and o-rings.

How long does it take to pump water after the motor is started, I would think immediately, am I wrong? Is there a thermostat in this motor.

Once again, thanks Joe for your help, I will let you know how I made out.

Doug Russell"
 
"Joe, sorry to keep pestering

"Joe, sorry to keep pestering you, but as I mentioned earlier you are dealing will a rookie.

I dropped the lower unit again as you suggested; I noticed I had pinched the grommet when re-installing the unit. The grommet has a slight tear at the top of the rubber flange, the rest of it looks alright, will this still be okay or do I need to replace?

Also should I install a new thermostat or how can I ensure the one I have is working?

I could not locate the boat armor sealer 1000, I checked Auto Zone, but they didn't have any. I was able to find some "3M Marine Adhesive Sealant - Fast Cure 4200", the package says it is good for below the water line, and will this work?

One last question, the Seloc manual I have calls for an o-ring at the top of the drive shaft, but no reference to the location or the size of the o-ring. Will this o-ring go in the groove just under the splines?

Thanks

Doug Russell"
 
"The slight tear shouldn't

"The slight tear shouldn't bother anything. Grease the grommet.

If water flows properly and the engine runs warm, even slight hot but not overheating hot, the thermostat is probably okay. However, after you're sure water is pumping properly, it would be a good idea to replace it.

I have no idea what "Fast Cure 4200" is. I prefer either Marprox Sealer 1000 or Boat Armor Sealer 1000 which should be available at any auto parts type store....... or what used to be called OMC Maine Adhesive which would be avail able at any Evinrude/Johnson dealership. I don't know what Bombardier calls it but they should have it. All three of these substances are the same thing.

Yes, that "O" Ring must be installed in that top grove and grease it and those top splines. Without it and the grease, those splines will rust tight to the crankshaft splines."
 
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