1966 Johnson 40HP outboard - cooling

[Classic Ski-Boat]

Re: 1966 Johnson 40HP outboard - cooling

1. Yes that's how they work and as far as water pump is concerned if it hasn't been replaced in a couple of years and you don't know when it was last replaced you should replace it.

2. Oil shouldn't be milky and if it is water is getting in from the drain plugs or one of the various seals in the lower unit.

3. You could try flushing it but it may not have a blockage, getting a new pump installed will tell for sure, just an added step.

4. It should by design and if it isn't it shold, plain and simple. Do the pump and flush then retest, too many unknowns.

Thank you. If I'll attempt the flushing, should I remove the thermostat? Should I just do it with a garden hose and connect it to the pipes that are normally connected to the water pump? Or should I flush from the thermostat point or from the upper (as I call it 'tell-tale') hot water outlet?

Thanks

 

[bktheking]

Re: 1966 Johnson 40HP outboard - cooling

Thank you. If I'll attempt the flushing, should I remove the thermostat? Should I just do it with a garden hose and connect it to the pipes that are normally connected to the water pump? Or should I flush from the thermostat point or from the upper (as I call it 'tell-tale') hot water outlet?

Thanks

Yes remove the stat, it won't be open when you flush it. Don't flush from the exhaust port in the back of the leg, flush it using one of the tubes going into the pump.