1956 7.5hp Johnson AD10M

[RJ045]

Just picked up last weekend fellow said hadnt run in about 10 years also got pressure tank with it for next to nothing thing started on about the 4th pull runs like a top only problem is no water I seem to remember reading here somewhere or being told that the depth of the water in the barrel up above the cavitation plate has an effect on this, could someone refresh my memory much appreciated I know it probably needs a new impeller but before I do that I thought I would check here.

Thanks all

 

[tomhath]

The water has to be well above the cav plate in order to prime the water pump. But if it hasn't been run in ten years you should just go ahead and replace the impeller. There are a couple gaskets/seals up at the powerhead you'll need to replace when you take it off (necessary to get to the water pump but not especially difficult). Also make sure the lower unit has clean gear lube in it.

I have the same motor, they're really nice.

 

[racerone]

Water should be about 10" above the cavitation plate.----Powerhead has to be removed to change the impeller.--Easy to do.

 

[F_R]

No Title

You will find this seal when you remove the powerhead. It is very vital that it be in good condition, otherwise water gets into the crankcase and destroys the internals. Always replace the 303355 gasket and 303347 o-ring, at the minimum

 

[RJ045]

Thanks all for the responses and F_R for the diagram.

 

[oldboat1]

may be of use: http://www.fiberglassics.com/library/index.php?title=Johnson

 

[Crosbyman]

http://boatinfo.no/lib/johnson/manuals/1922-1964johnson.html#/0

 

[RJ045]

Thanks for all the input all I want to change the fuel #303171 and Air #203286 lines was wondering what is being used these days ? dimensions etc.

Thanks Again