Johnson 40 Carb?

[Bill Mattor]

Hi, I have a 40HP seahorse thats running bad. Lw speeds it runs like a dream. When I open it up it almost reaches top end and then starts to sputter. Almost like to much fuel is chokng it out or to much air.<br />Any suggestions?<br />Thanks<br />Billy Maddog

 

[Paul Moir]

Re: Johnson 40 Carb?

Welcome to Iboats, Maddog!<br /><br />There's a bunch of different carbs and styles of 40hp Seahorses, so we're going to need your model number. On the older ones it was on the nameplate between the transom clamps, up on the tilt/swivel bracket. On later ones it was on the nametag rivited to the side of one of the transom clamps.<br /><br />In the mean time, does pumping the primer bulb when it's acting up have any effect?

 

[Bill Mattor]

Re: Johnson 40 Carb?

Hi and thanks for the iboat welcome. The model # is 2011854.<br />I have not tryed to pump the buld while it was running.<br /><br />What are you thinking of? Bad fuel pump? <br />Thanks<br />Billy Maddog

 

[MCM]

Re: Johnson 40 Carb?

Billy, I think that might be a serial #, the model # is what will help determine what yr. motor you have as well as any other characteristics it may have. If its a Johnson it will probably have at least 1 or more letters in it.

 

[Paul Moir]

Re: Johnson 40 Carb?

About the pumping thing - it proves a couple things depending on the effect. If pumping makes the outboard run better, then it indicates that there is either a fuel restriction, an air leak in the fuel line somewhere before the pump (usually the fittings), or a weak fuel pump. If it runs worse, that could indicate a broken pump diaphram or a leaking float needle in the carb.<br /><br />So as you can see, that relatively simple test proves a number of fuel system components are working right.

 

[Bill Mattor]

Re: Johnson 40 Carb?

Thanks Paul, That makes sense.<br />MCM, you are correct. The model # ia RDS2CC which is a 1960 model. <br /><br />Paul, would an original totaly fouled air <br />filter play any role in this? I did find a few loose clamps on some fuel lines which helped on the lower speed issue I was having. They are all new fuel lines. This motor has about 35 origanal hours on it so it has to be something at least as stupid as me.

 

[Bill Mattor]

Re: Johnson 40 Carb?

Paul, me again. I have it my shop right now. Gonna get it in the test tank this weekend if I don't have to do the holiday thing, which I'm sure my sevices will be called upon to put up lights, stir the egg nog or something.<br />Well at least its not fishing season, and the lakes around me are starting to ice up big time.<br /><br />Billy Maddog