1969? Johnson 4 HP

[penn136]

A motor was given to me by my grandfather along with my first boat. The model number is 4W69B<br />I am assuming that the year of the motor then is 1969. <br />My question is, after rebuilding the fuel intake and repairing a broken pull cord. The motor will start but won't stay running unless I continually pump gas from the tank to the engine. Where do I go from here?

 

[Paul Moir]

Re: 1969? Johnson 4 HP

You're correct about the year. That model number is from the breif period you didn't need a secret decoder ring to figure out years (Johnson, '69-'79).<br />First, if you don't suspect the fuel pump (fuel intake?) start looking for air leaks. Most likely suspects are cracked fuel lines between the fuel pump and the primer bulb, and leaking o-rings in the fuel line connector on the front of the engine.<br />You can quickly test the fuel pump by removing the fuel line from the carburetor. When you pull the pull-cord, you should see pulses of fuel coming from the line. <br />Funny - I'm working on my 'new to me' '72 4hp Johnson this evening. It's starting to come good.

 

[penn136]

Re: 1969? Johnson 4 HP

Thank you for your advice, i will have to check the lines and get back to you. Since this is my first motor I am thinking of letting a marina do a lookover on it and tell me what they think too. Ill get back in touch though. Thanks again.

 

[penn136]

Re: 1969? Johnson 4 HP

I asked a local marina and they told me it wasn't worth it for them to even take a look at the engine. That I should just junk it and buy a new one. I am determined to rebuild this engine and teach myself how to do it. With help from this forum it should go pretty well.

 

[Paul Moir]

Re: 1969? Johnson 4 HP

I was afraid they would say that. But that's a great engine. You should fix it.<br /><br />Here's a good article on tuning up an old 3hp, which is a lot like our 4hp engines but has a different head, reeds and no exhaust tuner. Otherwise it's virtually the same.<br /> Really good 3hp article, click here.<br /><br />Good luck!

 

[penn136]

Re: 1969? Johnson 4 HP

thanks for the help. I appreciate it and hopefully it will get me started.

 

[penn136]

Re: 1969? Johnson 4 HP

I have already ordered the manual for that whole set of years of Johnson engine's, and I do understand from the marina'a perspective as far as it not being worth it for them. Although I did tell them that I would pay whatever it took just to get it up and running for the season. But their response just makes me more willing to do this all myself and settle for paddling with oars for the rest of the season. Thanks for the support.