9.9 hard to start cold...

12guns

Petty Officer 2nd Class
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Oct 30, 2006
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1977 Johnson 9.9 w/ 15 hp carb, open air intake (under cowl) and no exhaust baffle, and appx 30 hours or run time. Runs like a top, but last duck season when starting at or around freezing, I had to keep pumping the primer bulb when it would starve for fuel. Once it warmed up, it ran fine. A week ago I took it out on the lake (warm water) and it ran awsome. Today I cleaned the fuel pump filter and w/ cold hose water running thru the muffs, it will start 1st crank, but starve for fuel a min or so later. What's the deal? Fuel pump? The filter looks clean, and I'm pretty sure I put it back together right. Famous last words. Any advise would be great. It's frustating having this motor that runs so well, but is diff to start when cold.
 

ezeke

Supreme Mariner
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Sep 19, 2003
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Re: 9.9 hard to start cold...

What's wrong with your choke?
 

reload

Petty Officer 1st Class
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Jun 29, 2004
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368
Re: 9.9 hard to start cold...

Check to see if the choke is closing fully. Sounds like pump may be the culprit, I would replace. It may be marginal in the warm weather and just not cut it when cold.
 

12guns

Petty Officer 2nd Class
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Oct 30, 2006
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123
Re: 9.9 hard to start cold...

I'm leaning towards the fuel pump myself. The choke works fine, it will keep it running for a while, but eventually it still starves for gas. I'll get a new pump and see what happens. Thanks guys.
 

12guns

Petty Officer 2nd Class
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Re: 9.9 hard to start cold...

Ok, now I'm second guessing myself on the re assembly. I looked at the pre-existing imprints, and Think it's together right, but it strikes me as odd that it ran so good last week and after I messed w/ it, it doesn't. Where can I get a blow up showing which way each square piece should be turned?
 

12guns

Petty Officer 2nd Class
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Oct 30, 2006
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Re: 9.9 hard to start cold...

That link helped more than anything. I can't find anything that looks bad or out of place, the pump was replaced in 2000 and taken care of since. Everything is in it's place, and should work. If not I'll check the gas lines and go from there. The internal fuel lines were replaced w/ the pump and are in good cond. QUESTION...What if I tightened the thumb screw too tight and the outer orange colored gasket were old and starting to dryrot?? could it allow too much air in? or be causing my problems? I noticed the last time I put it together I had tightened it and tor a small area in the middle. I'll replace it tomorrow, probably along w/ the whole fuel pump just to be sure. Thanks again.
 

12guns

Petty Officer 2nd Class
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Oct 30, 2006
Messages
123
Re: 9.9 hard to start cold...

can I tighten the thumb screw too tight and close off the fuel flow?
 

67Johnson6HP

Petty Officer 2nd Class
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Jun 14, 2007
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Re: 9.9 hard to start cold...

Probably need to start a new thread to get an answer to your last question.
 

12guns

Petty Officer 2nd Class
Joined
Oct 30, 2006
Messages
123
Re: 9.9 hard to start cold...

The thumb screw I'm talking about is on the fuel pump, could be the problem w/ the eng starving for fuel. It's related to this post. Same problem. Thanks
 

12guns

Petty Officer 2nd Class
Joined
Oct 30, 2006
Messages
123
Re: 9.9 hard to start cold...

Fuel pump kit did the job! The first time I put it on wrong but quickly found my mistake. Thanks for all the help!!
 
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