1964 3hp yachtwin water pumping problem

[gmctruck]

1964 yachtwin 3hp.I just got this motor.I cleaned the carb, installed new coils, checked out the water pump (its fine),fresh gas 50:1. the thing fired up first pull. my question is where does the water come out of on the motor? I dont want to over heat it. if anyone could point me in the right direction that would be great. thanks

 

[mikesea]

Re: 1964 3hp yachtwin water pumping problem

Thee are small slits or holes just below the powerhead on the rear of the stem .BUT,you said the pump is fine.Unless it was changed last yr.I doubt it.Impellers cannot "TAKE SHAPE"the vanes need to have ability to fully extend.Under power they get smaller.What looks good,often is not.Why take the chance over a few dollar part.Your engine dont have a tell tale squirter.It kinda mists the water out the relief port I described.Be sure to feel the head for first few runs.Be sue to run it it a well filled basin of water or on a boat.It doest have a port for the muffs seen on other engines

 

[Vic.S]

Re: 1964 3hp yachtwin water pumping problem

I agree if the impeller is more than a year or so old change it.
It is silly IMHO to go to the trouble of dropping the gear case and opening up the pump and then putting the old impeller back.

The bulk of the cooling water leaves with the exhaust under water where you cannot see it. You should just get a little blown out of the exhaust pressure relief ports though as said above.

You mention using a 50:1 fuel mix. the Official line is than most motors from 1964 onwards should run on 50:1 but these ones do not have needle bearings at all on the crankshaft. Because of that a 24:1 mix might be advisable.

 

[gmctruck]

Re: 1964 3hp yachtwin water pumping problem

i'll get a new pump for it and see if that does it. thanks for the info mikesea

 

[gmctruck]

Re: 1964 3hp yachtwin water pumping problem

im only running 50:1 because the sticker on the tank says run 50:1 but i will keep that in mind

 

[Vic.S]

Re: 1964 3hp yachtwin water pumping problem

If it says 50:1 on the tank then that's fair enough . Just dont be mean with the oil. A bit extra will do no harm and might just be beneficial.