1960 18hp johnson not pumping water in neutral

Joined
Sep 10, 2007
Messages
6
When starting from cold will spit water out in neutral but after shut down and restart it won't spit any water out but if it is put in gear it does.
 

Joe Reeves

Supreme Mariner
Joined
Feb 24, 2002
Messages
13,262
Re: 1960 18hp johnson not pumping water in neutral

Install a new complete water pump assembly.
 

F_R

Supreme Mariner
Joined
Jul 7, 2006
Messages
28,226
Re: 1960 18hp johnson not pumping water in neutral

Agreed, the pump is worn out. OR, you don't have it deep enough on the water. Are you running it in some sort of a bucket?
 
Joined
Sep 10, 2007
Messages
6
Re: 1960 18hp johnson not pumping water in neutral

I am running it in a barrel and the water is high enough.it will pump water but not always in neutral if u put it in gear and then back in neutral it will pump in neutral.had lower unit apart and impeller looked good.
 

Joe Reeves

Supreme Mariner
Joined
Feb 24, 2002
Messages
13,262
Re: 1960 18hp johnson not pumping water in neutral

You've received excellent advice. Replace the complete water pump. That will solve your problem UNLESS you have a failing head gasket that would be allowing the combustion power enter the water passageways causing a stalemate which isn't likely.
 

samo_ott

Vice Admiral
Joined
Jun 18, 2006
Messages
5,125
Re: 1960 18hp johnson not pumping water in neutral

I agree. Impeller AND housing. It's weak. My '66 18 did the same last year. I replaced the impeller and the water flow was still weak, almost non existant in reverse, then I replaced the housing (which looked fine) with a different used one and it pumped great, even in reverse.
 
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