72 Johnson 20 H P loosing prime from tank

[E.T. Wallace Jr.]

Hi, I am new on this forum so be kind. I have a 72 johnson 20 H P that has been sitting for several years. I put in new plugs,cleaned the points,new gas and marine additive.The motor fires up easy,But it spits and idels rough. When you run open it will start to die out and it has lost the prime,you can pump the bulb and it will run fine.I changed the line and the connection also. Help up the creek without a prime.

 

[mercury1]

Re: 72 Johnson 20 H P loosing prime from tank

First option would be to replace the fuel pump. The diaphram is probably dry cracked and not pumping enough fuel to keep the fuel level in the bowl full.<br /><br />My 2 cents

 

[JB]

Re: 72 Johnson 20 H P loosing prime from tank

I agree with Merc1.<br /><br />Except that I would overhaul the fuel pump rather than replace it. Wouldn't hurt to overhaul the carb, too.<br /><br />Check that there are no restrictions or air leaks in your fuel lines and tank pickup, too.<br /><br />Good luck.

 

[E.T. Wallace Jr.]

Re: 72 Johnson 20 H P loosing prime from tank

Thanks for the help. I think I will try rebuilding the pump first. Any idea of where to get a kit for the pump?<br /><br />E.T.

 

[JB]

Re: 72 Johnson 20 H P loosing prime from tank

JohnnyRude dealer or NAPA Auto Parts store.<br /><br />Good luck.

 

[E.T. Wallace Jr.]

Re: 72 Johnson 20 H P loosing prime from tank

Thanks Red Sky at night.. I get it today and post again tonight.<br />E.T.