Help!! 87 Johnson 30hp will not start

jdoug

Cadet
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Jul 20, 2013
Messages
11
Hello Gents,

I am new to the forum and from what I can tell y'all know your stuff. I was hoping y'all could help me out. I traded for a 1648 mod-v and a 30hp Johnson a while back. The guy said the carb was gummed up but other than that it ran great. So being the trusting person I am I believed him... Mistake. I've clean the carb 3 different time, soaked it over night, I've pulled and cleaned the fuel pump, changed spark plugs (gapped at .030), and put a new fuel line from the tank to the motor. I got it running a couple weeks back and let it run for 15-20min with the muffs on and everything seemed great. I went out the next day and tried again and nothing. Clean the carb again and still nothing. I don't have the tool to check compression but when it ran it ran good.

What else can I check?
 

pn

Petty Officer 1st Class
Joined
Apr 20, 2013
Messages
374
Re: Help!! 87 Johnson 30hp will not start

since you've gone through the sticky on the top of the page and followed all the steps...check your kill circuit/grounds.
 

boobie

Supreme Mariner
Joined
Nov 5, 2009
Messages
20,826
Re: Help!! 87 Johnson 30hp will not start

Have you checked your spark with a spark tester set at 7/16 " open air gap??
 

jdoug

Cadet
Joined
Jul 20, 2013
Messages
11
Re: Help!! 87 Johnson 30hp will not start

I've checked the grounds and they are good. Also checked the spark and I am getting a good spark. I am going to check the compression tonight when I get home. It still sounds like it isnt getting fuel through the carb. I was looking on ********** and something caught my eye. On the below picture below my carb doesnt have number 1 or 29. It doesn't have a price for them either it says they are obsolete which makes me think they are not needed but number 1 seems important.



carb.jpg
 

jasper60103

Commander
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Sep 18, 2008
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pn

Petty Officer 1st Class
Joined
Apr 20, 2013
Messages
374
Re: Help!! 87 Johnson 30hp will not start

i'm pretty sure you need that, idle air adjustmet screw, mixes air fuel ratio for idle. it's not deep down in the hole? or deep down in your cowl? take a look around.
 

jdoug

Cadet
Joined
Jul 20, 2013
Messages
11
Re: Help!! 87 Johnson 30hp will not start

Jasper looks like you are right, my carb must be a later model than the motor. Picture of my carb is below. I am going to take out the low speed needle and clean it this weekend and hopefully that will get her running again. I checked compression last night and both cylinders were just over 100PSI.

carb.PNG.jpg
 

AlTn

Commander
Joined
Mar 9, 2010
Messages
2,813
Re: Help!! 87 Johnson 30hp will not start

in the link Jasper provided..parts # 1 and 22 need to be spotless, make certain gasket, #30, is in place as well
 

jdoug

Cadet
Joined
Jul 20, 2013
Messages
11
Re: Help!! 87 Johnson 30hp will not start

I clean out the low speed really well and got everything back on and it started and ran really well for about a minute and them died again and won't start. FML
 

jdoug

Cadet
Joined
Jul 20, 2013
Messages
11
Re: Help!! 87 Johnson 30hp will not start

Also I notice when pumping the bulb on the gas line it never gets firm. Isn't it supposed to get firm?
 

jasper60103

Commander
Joined
Sep 18, 2008
Messages
2,055
Re: Help!! 87 Johnson 30hp will not start

Also I notice when pumping the bulb on the gas line it never gets firm. Isn't it supposed to get firm?

Yes, it should feel firm as the carb bowl fills with fuel.
Did you happen to notice if gas leaked from the carb?
When you had the carb off, did you adjust the float and make sure the float needle (#16) is in position?
 
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