6hp johnson will not run at idle

[spuds69]

Hello,I have a 6 hp johnson that
runs fine on top end,but dies at idle speeds.I was told its a 1986 model but I don't know.The model number is J6rcde.The gas is new,the carb has been cleaned,and it has new spark plugs. I have spark at the spark plugs,but looks weak.Looking at buying new coils and tune up kit.Any information will be appreciated as I'm new to the forum.

 

[crxess]

Re: 6hp johnson will not run at idle

Carb was cleaned. How? Was it rebuilt?

The carb needs to come apart and soaked in a proper carb cleaner or at least rinsed with a carb cleaning spray.
The High speed Jet behind the drain screw needs to be cleared with a proper sized piece of wire or a welders file.
The soft plug needs to be removed and the tiny passages cleaned the same way. This part is the IDLE circuit.
You will need the rebuild kit for the new soft plug and fuel shut off valve assembly along with new gaskets and fresh packing for the low speed adjustment needle.

 

[spuds69]

Re: 6hp johnson will not run at idle

Thank you for your reply.The carb was cleaned thoroughly with carb cleaner and fine wire inserted in all openings.You lost me with the jet behind drain screw.I don't recall a drain screw on this carb.There is a screw to adjust the idle and a screw on the front of the carb that can only be accessed with the carb out.Is this the drain screw? Thank you for your time. P.S. I do plan on buying a rebuild kit for the carb.

 

[Vic.S]

Re: 6hp johnson will not run at idle

Carb diagram HERE but there's a problem with the numbering (used 19 twice!)

"Drain plug" is #18 and the high speed orifice is behind it.

Don't use anything more aggressive than soft copper wire for cleaning jets.

Have you set the idle adjust screw #15 correctly. See Joe Reeves article on Adjusting carb needles on the "Engine FAQs" Board


By the way J6RCDE is an '86 model. CD = 86.

Sparks should jump 7/16" from the end of the leads.

 

[crxess]

Re: 6hp johnson will not run at idle

With the carb off the motor. Looking into the throat from the back side. you will see (2?) tiny holes. These feed the fuel at idle. They can only be cleared by removing the soft plug in line with the holes. this is the end of the passage from the low speed adjustment. If they are blocked, no amount of adjusting will correct the idle.

Follow Vic's advice on cleaning and proper adjustment.

 

[spuds69]

Re: 6hp johnson will not run at idle

Thanks to everyone for their input.It's dark out now so I'll investigate more tomorrow.I will report back with what I find!Thanks again!

 

[spuds69]

Re: 6hp johnson will not run at idle

Hello everyone! I took the carb off again and looked for the drain plug with no luck. I looked for it in the location that the diagram Vic.S was nice enough to share shown it.The only "port" on the bottom portion of the carb is where the fuel line connects.Looking into the throat from the back of the carb there are four holes.One by itself the size of a large needle,and three in an indented place with one the size of a medium needle,and two roughly same size of tiny needles.I could find no soft plug in line with these holes.
I do have numbers off of the carb.Maybe the carb has been replaced with the wrong type?? These numbers are stamped on carb body (331733).
These numbers are stamped on a small tag (396513 mx 11 k k).
Thank you for your patience and your time.

 

[crxess]

Re: 6hp johnson will not run at idle

For some reaasin the '86 breakdown for your carb has some typo's, in all motor versions.

I pulled up the '87 information(same carb) and it is corrected.
Exactly opposite the fuel inlet should be a hex screw. This is the drain. directly behind it is the high speed orifice.

Your carb is quite different from earlier 6hp models. No Soft Plug. instead, the upper portion of the carb is removable for cleaning the passages.

http://shop2.evinrude.com/Scripts/I...18\08.TIF&ilSC=50&ilIV=0&ilBR=0&ilIF=P&ilRE=8

 

[spuds69]

Re: 6hp johnson will not run at idle

Thank you for replying crxess! I have the carb in hand and there is no other opening other than the fuel port.Directly across from it there is a place that appears something should have been tapped but never was. I have this amazing ability to run into odd things on all my mechanical issues.Standard responses from people are "Been doing this for thirty years and I have never seen this before!"LOL!! Thanks again for your info and time!!