Johnny not starting up cold and dies when idle....

HTownBoi281

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May 18, 2004
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Hey guys. I have a '74 Johnson 115 outboard in need of some help from some of you professionals. Heres the deal, I've just rebuilt the carbs on it, cleaned up the whole engine, replaced the spark plugs with ones that are the same, put in a fresh new battery and fresh fuel, and checked compression and all cylenders are all the same and are fouled. My problem is when I take the boat out, when I try to crank the boat, It will not start without a shot of starter fluid. I know its bad to spray that junk and I dont wanna spray anymore thats why I did all the things metioned above. And when I get the motor running, it runs fine until I idle for a little bit and it dies out. Even when I'm running at low speed the motor wants to die out until I give it some more throttle then its fine. I didnt have any of these problems with my other boats so can anybody please give me some tips on what to do??
 

HTownBoi281

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Re: Johnny not starting up cold and dies when idle....

continued from post...when the engine dies out at idle, I have to spray some more starter fluid in there to get it running again. I'm tired of doing all that stuff over and over to get it running not to metion on a rough day its not too safe to be leaning over and doing all of that.
 

cobra 3.0

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Re: Johnny not starting up cold and dies when idle....

Sounds fuel related. Have you changed the gas filter? Also,your fuel pressure may be low and your fuel pump may need to be replaced.
 

HTownBoi281

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Re: Johnny not starting up cold and dies when idle....

thanks cobia, i've checked the fuel filter and it was clean as a whistle and changed it just to be on the safe side and i've also added an inline fuel filter also. how would i check if it is the fuel pressure and the fuel pump??
 

angus63

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May 20, 2002
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Re: Johnny not starting up cold and dies when idle....

try continously pumping the bulb after a cold start and see if it keeps running. If it keeps running, most likely an airleak or fuel pump.
 

HTownBoi281

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Re: Johnny not starting up cold and dies when idle....

thanks for the tip Angus63. i'll try that this weekend and see what happens. But does anybody know what the compression ratio is for this motor?? cause i was talking to a boat mechanic friend of mine and he said it sounds like i have low compression. i've checked it out before and all the cylenders were the same but i forgot what it was now since i dont have compression gauge anymore and when i get it cranked and running full throttle, its running better than the original owner had said.
 

Brew2

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Jan 12, 2004
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Re: Johnny not starting up cold and dies when idle....

While you are tracking down your problem, you might want to put some pre-mixed gas/oil in a spray bottle and use that instead of starter fluid to spray into your carbs. Using much of that starter fluid is a sure fire way to fry a cylinder due to lack of lubrication.<br /><br />Good luck!
 

HTownBoi281

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Re: Johnny not starting up cold and dies when idle....

Thats a great tip. Didnt think of that. Thanks Brew2
 

ezeke

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Sep 19, 2003
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Re: Johnny not starting up cold and dies when idle....

I run a 1976 115 and a 1973 135, which are very similar motors. <br /><br />On the starting problem, you need to be sure that the choke is closing 100% on both carbs when you hit the choke switch and that they are synchronized. You cannot check this with the manual override, but nust have someone hit the choke switch while you watch the choke. If the choke flaps don't close completely, and I mean completely, move the solenoid down in 1/16 intervals until they do, and then make sure that they are fully closed at exactly the same time. <br /><br />I'm thinking along with Angus63 Cobra 3 and Brew2 on everything else, especially regarding the fuel pump.<br /><br />Regarding the compression, you will want to post the values here for the techs. Everyone else will want to see all within 10% of each other.
 

HTownBoi281

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Re: Johnny not starting up cold and dies when idle....

ok here it is guys. (1)-125 (2)-125 (3)-123 (4)-123. Give .5 on cylenders (3)&(4). And I've just checked the choke flaps and had my neighbor hit the switch for me, and they do close all the way. I can tap on it and i wont hear any clicks which means its seated tight to the walls of the carbs. and i've just rechecked it for spark and i do have spark on all plugs. Its driving me NUTS. PLEASE HELP!!
 

HTownBoi281

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May 18, 2004
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Re: Johnny not starting up cold and dies when idle....

i heard about decarbing the motor with the seafoam. i have the seafoam all this time just never knew how to decarb till now. maybe that'll help cause i dont think this motor's ever been decarbed. i'll try it and see if that will bring up my compression a lil bit more. hopefully. thanks.
 

cobra 3.0

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Re: Johnny not starting up cold and dies when idle....

Your cylinders look just fine. Did you go out and keep pumping the fuel bulb? (Also, this is a dumb one, but it happened to me...Do you have your fuel hose in the right direction?)<br /><br />If pumping the bulb works, get a new fuel pump.
 

ezeke

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Re: Johnny not starting up cold and dies when idle....

I thought I might share one other thing that might help. <br /><br />When I first bought the 115 Johnson, I had the same cold starting problem that I've read about here from this thread and a lot of others. But every time I took it to the dealer it started immediately for them. <br /><br />I finally saw that they were using a quick charger clamped on my battery.<br /><br />After that I got the largest marine battery that I could find and that solved the problem.
 

HTownBoi281

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Re: Johnny not starting up cold and dies when idle....

thanks guys, ummmm, im pretty sure my hose is in the right direction. i havent tried pumping the bulb yet cause it was getting kinda dark and i didnt wanna disturb the neighbors. I'll give it a whirl later. oh and ezeke, could you tell me how many cold cranking amps you had on that big battery you bought?? because i bought this new battery, and it has 500 Cold Cranking Amps which is better than the battery it had before with a little better results. i can tell when i crank the engine, it turns over faster than the old battery with 450 CCA. maybe i need a battery with higher CCA's. thanks guys.
 

ezeke

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Re: Johnny not starting up cold and dies when idle....

My battery is 700CCA. Backup is a 650 Diehard marine.
 

HTownBoi281

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May 18, 2004
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Re: Johnny not starting up cold and dies when idle....

hey guys, took my boat on a test run today out on the water. did a couple of WOT runs and idle runs for about 25 minutes. motor running good except 1 new problem. when i put my boat back on the trailer and tied it down, i decided to check the spark plugs again and found that cylender 1 is running dry and the other 3 cylenders are moist (fouled). can anybody please tell me what the cause of this problem is and how i go about fixing it. thanks.
 

ezeke

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Re: Johnny not starting up cold and dies when idle....

Are you saying that # 1 spark is clean? <br /><br />If so you may be gettting some water in there. Try re-torque on heads now that you've run it. <br /><br />Reasoning: I would expect some fouling on all spark plugs unless running at full power range. <br /><br />If re-torque doesn't solve the problem, you might consider new head gaskets. <br /><br />Lastly, you may not be getting proper fuel/oil to the # one barrel which would suprise me if you can hit WOT. BUT, if that's the case, your jet's could be clogged.<br /><br />You also might consider another compression test.
 

Solittle

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Re: Johnny not starting up cold and dies when idle....

What exactly did you do when you rebuilt the carbs - be specific? Did you do a sync & link? Timing?
 

HTownBoi281

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Re: Johnny not starting up cold and dies when idle....

well....its fouled but its a dry foul. its not wet like the others but i definitly see carbon on it and i did test it for spark again and it does fire. i hope u guys know what im talking about. i rebuilt the carbs and sync'd it and link'd it but i didnt do the timing on it cause i dont think i have enough know how on how to do and still a lil "iffy" if i should tackle the timing myself or do it with somebody that knows how to do it. i dont wanna get into and set the timing all out of wack then chunk my motor into the trash. i wanna make sure i know step by step how to do it before i tackle something like that.
 

cobra 3.0

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Re: Johnny not starting up cold and dies when idle....

A manual is essential in doing your own repair and maintenance...as essential as your socket set and screw drivers!!! ;)
 
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