1988 johnson 30hp running lean or rich wont go full throttle

[grizzrider09]

Hey guys I'm helping my neighbor sell his boat and we are trying to get this motor going. I have cleaned the carb and put In a new water pump. The motor cranks really easy and idles good with the choke on but take it off and it will pop pop pop and die. Where do I adjust the low speed needle? Also when you open it up on the lake it's like it's not taking the gas. It only runs about 5mph but you can are lots of gas being sprayed in the carb when you take the top off. I have checked the spark and it will jump a 3/8 gap so I think that's good. Any suggestions on what to do and how to adjust. I'm going to clean the carb again tomorrow

 

[Daviet]

Re: 1988 johnson 30hp running lean or rich wont go full throttle

Static setting on the low speed needle should be 1 1/2 turn out from lightly seated, you will have to fine tune it on the water and in gear.
When cleaned the carb, did you remove the core plug on top and make sure the passages in there were clean?

 

[grizzrider09]

Re: 1988 johnson 30hp running lean or rich wont go full throttle

I didnt remove the core plug but Im not exactly familiar with this carb. On my 20hp Johnson the low speed need can be adjusted from the front of the carb but this carb it doesnt stick out like that. If your in front of the motor looking a the carb there is a screw on the left side of the carb on top where the needle would seat that can be screwed in and out. Is that the static settting you refered to. If it is I tried 1 1/2 turns and it is still popping while idling. I adjusted it all the way in and out and the only difference was when it was all the way out it wouldnt idle. I had it on the muffs while doing this. Do you really think it would make a huge difference with it being in the water vs on the muffs?

 

[Daviet]

Re: 1988 johnson 30hp running lean or rich wont go full throttle

I looked at a couple of 1988 30hp carbs and they had the low speed needle in the front of the carb, what is your model number?

 

[grizzrider09]

Re: 1988 johnson 30hp running lean or rich wont go full throttle

j30lcce. i will post a pic if i can

 

[grizzrider09]

Re: 1988 johnson 30hp running lean or rich wont go full throttle

sorry its j30elcce

 

[Daviet]

Re: 1988 johnson 30hp running lean or rich wont go full throttle

Below is a parts breakdown of your carb.
#1 is the low speed needle and should stick out of the front of the carb, does this look like your carb?
:: iShopMarine.com ::

 

[grizzrider09]

Re: 1988 johnson 30hp running lean or rich wont go full throttle

I have tried to upload the pics but for some reason my computer is not wanting to cooperate. The pic you have linked is not the carb that I have so I looked at a pic of a 40 hp carb and it looks identical. Now my next question is, supposing this is a 40hp carb on a 30hp motor is there anyway this will work or will he just have to get the right carb?

 

[grizzrider09]

Re: 1988 johnson 30hp running lean or rich wont go full throttle

 

[likitvi]

Re: 1988 johnson 30hp running lean or rich wont go full throttle

Judging by the picture, and EPC, your motor has carburetor from a newer model with electronic primer instead of choke butterfly. E.g. 1990 30hp has similar. Atleast that bowl is not from the 40hp carburetor, but they could share the same body and somebody could have mix and matched the parts, who knows. Try to locate the part number on the carburetor body and bowl for starters. (1988 30hp has the electric primer already, but the carb body is different and it should have an adjustable low speed needle on top of the throat.)

That carb has fixed jets, or orifices, and you should carefully remove them from the body with a correctly shaped tool for identification and ensure they are correct size. Low speed is located in the bigger on top of the throat and high speed behind the drain plug.

 

[likitvi]

Re: 1988 johnson 30hp running lean or rich wont go full throttle

Also, ensure that needle valve in the carb is not stuck open or worn and the float inside the bowl is in order.

 

[Jim Hawkins]

Re: 1988 johnson 30hp running lean or rich wont go full throttle

View attachment 212209View attachment 212210

This is my 30HP Johnson J30ELCUB Yours has a brass screw adjustment behind the linkage



Your idle adjustment screw is not in the photo, did you have it in when running?

 

[grizzrider09]

Re: 1988 johnson 30hp running lean or rich wont go full throttle

Jim i have no clue. I was about to ask what the brass srew is on top of the carb and just about all the way back and if that was not where you can adjust your lean and rich then where do i adjust.

 

[grizzrider09]

Re: 1988 johnson 30hp running lean or rich wont go full throttle

Ok I was looking at the 1990 30hp carb and this does look like it but on the bottom of the carb on a 90 model there is a johnson part number 0326467 that is a nipple. From the pics mine doesnt have that nipple. Im extremely confused as to what someone did here but I just need to get this thing running. I am going to tare down the carb again this afternoon and soak it all night in some carb cleaner. Maybe by tomorrow afternoon this thing will be ready to rock and roll. Any suggestions are welcome any thing else I need to do to get her fixed. Thanks guys

 

[Jim Hawkins]

Re: 1988 johnson 30hp running lean or rich wont go full throttle

Well I'm also confused,

First, in your picture I don't see the low speed needle sticking out of the hole in front and on top of the carb. Do you have a needle that screws in there? (part #1 in the diagram) If so do you also have #17 the retainer? If they are supposed to be there and are not that might explain your problem.

 

[grizzrider09]

Re: 1988 johnson 30hp running lean or rich wont go full throttle

Jim I want to say after looking at several diagrams this carb is a 1990 30hp carb which doesn't have that low speed needle your talking about but I'm not sure on that either. I got the carb off and soaking in cleaner now and I'm going to let it soak all night and all day tomorrow then blow it out with a air hose. If that doesn't do the trick I'm quiting on it

 

[Jim Hawkins]

Re: 1988 johnson 30hp running lean or rich wont go full throttle

One thing I learned on this forum is to also wash out the carb with warm soapy water. Now when I do a carb I soak it in cleaner, take it out and soak it in a bucket of Hot water with a little dish soap then blow it out and repeat the process again or even twice.

I'd take it out in the morn, wash, blow dry and back into the soak.

 

[likitvi]

Re: 1988 johnson 30hp running lean or rich wont go full throttle

Locate the part numbers on your carb body and bowl. That will tell help acquiring correct parts if needed.

Also, open the bowl in any case to check and renew gaskets, float and needle valve as necessary.