1986 6hp johnson dies at idle speed

[spuds69]

Hello,I'm still fighting my 6hp on low idle.I've soaked and cleaned and rebuilt the carb to no avail.The motor will run about 15 seconds then die.If I get it to medium to high rpm's it runs fine.
It acts like it is starving for fuel,but the next pull it will fire off and run another 15 seconds before dying.When running it has a hard miss that twitches the tiller handle.crxess was kind enough to show a exploded diagram of the carb,but my carb has no drain plug with high speed jet behind it.I would also like to know the function of the knob surrounding the kill switch at the end of the tiller. Thank you for your time.

 

[Marvxyz2]

Re: 1986 6hp johnson dies at idle speed

The knob is for the lanyard which is a short piece of cord and when it isn't there, the motor will not run, come to think about it my lanyard is also missing, also !!

 

[iwombat]

Re: 1986 6hp johnson dies at idle speed

Have you performed a spark check and compression test?

 

[spuds69]

Re: 1986 6hp johnson dies at idle speed

Thanks for replies!I haven't checked compression,but I have pulled the plugs and the spark seems ok.As far as the knob on the end of the tiller there was no lanyard there when I bought it and has ran.Thanks!

 

[Vic.S]

Re: 1986 6hp johnson dies at idle speed

The knob surrounding the kill switch is the idle speed adjustment! Turning it clockwise increases the idle speed and vice versa. It is quite a fine adjustment, needing quite a bit of turning to produce much change in speed.

Your carb should have that plug on the side of the bowl but an '85 carb did not have that plug .... but different design altogether ...see HERE

Have you tried playing with the choke. (It is a primer pump on a '86 but a flap type on earlier models.)
Does pumping the fuel line bulb make any improvement which would point to a fuel pump problem or an air in leakage.

Is your slow running mixture adjustment correct (See Joe Reeves' instructions on the Engine FAQs board)
Have you simply got it set too slow. In addition to the knob on the tiller there is a stop screw on the carb on an 86.

You need to find the cause of the misfire. Have you tried new plugs?

My '84 6hp idles faultlessly at 900rpm. Carb has never been touched.

 

[Vic.S]

Re: 1986 6hp johnson dies at idle speed

There is no safety lanyard on an '86 model. Just a push button to stop it (Just like mine) Lanyard was fitted to later models (87 onwards maybe ?)

 

[spuds69]

Re: 1986 6hp johnson dies at idle speed

Thanks again for replies.Thank you Vic.S for the link but thats not my carb.crxess provided link that does show my carb exactly except mine has no drain plug on the bottom of the carb.Pumping the fuel bulb makes no difference.There's really no choke but a primer knob to pull out.I've been told in prior posts that it bypasses the carb to help starts.I've tried Joe Reeves instructions to adjust low idle but it dies before I can adjust it much.I've also tried to adjust through the tiller handle but with no success.The plugs are new and gapped properly.There is an "electronics board" that the wires from under the flywheel go into.Is this the power pack. I have also pulled the flywheel there aren't any points under it. Thank you for your input guys.I know its going to be something simple but I'm pulling out hair that I can't afford to lose!!

 

[crxess]

Re: 1986 6hp johnson dies at idle speed

Just to chime in.
The drain is not on the bottom, but on the side of the bowl.

There seem to be several contradictions going on. can you post your model/serial from the id plate?

Put a little pre-mix in a spray bottle. Idle down as low as possible without stalling. Spray a little in the carb and see it it picks up.

The trick with setting proper idle is patients. You have to give the motor time to recover and settle between incremental adjustments.

Also make sure you are not trying to idle to low. Check for a stop adjuster to keep the handle from turning idle to far down.

 

[Vic.S]

Re: 1986 6hp johnson dies at idle speed

can you post your model/serial from the id plate?

He already did. It is J6rcde. So it is a 1986 model!

My fault for causing confusion but I just wondered if it had an earlier carb fitted for some reason ... Spuds confirms though that that is not the case.

 

[crxess]

Re: 1986 6hp johnson dies at idle speed

Thanks Vic.
I went back to the diagrams. Carb changed completely from '85 to '86. It was modified again in '90, loosing the drain plug. Still shows the high speed orifice around the bowl location.
http://shop2.evinrude.com/Scripts/I...77\09.TIF&ilSC=63&ilIV=0&ilBR=0&ilIF=P&ilRE=8

It is possible the jet was incorporated into the nozzle well fitting.
It is possible the carb was replaced with a later unit, even mistakenly one for an 8hp.

If this was done, perhaps even to gain fuel flow for more power, it could be causing your problems.

 

[ScottinAZ]

Re: 1986 6hp johnson dies at idle speed

one other thing to be aware of, if the head gasket is leaking, the engine wont idle for beans. both gaskets on my 115 were leaking, but not blown, and the engine would not idle for crap. Changed them out, and its like a new motor. If all else has failed, and it still wont idle, then replacing the head gasket may solve the problem.


BTW, a leaking gasket may not show up on a compression test, mine still showed 110-115 on all holes, even with the seeping gaskets

 

[spuds69]

Re: 1986 6hp johnson dies at idle speed

Thank everyone again for responding.I'm at wits end with this carb.Thank you crxess for supplying link,but that's not the carb either.I'm afraid various parts have been combined on me.The bowl on the new link looks like mine,and the carb from the 1987 looks like mine.I've heard the plastic bowls are prone to cracking.I guess I'll try to buy new bowl for 1987 model.Another issue I'm curious about is the "power pack". Is this engine equipped with one?There appears to be an electrical board on the engine.Where the wires enter the board there is blackening and discoloration that I see through the clear resin.Would this cause my problems,and if so how would I test?I've owned this motor about a month and it's never ran right.
Thank you again for you time gents!

 

[Vic.S]

Re: 1986 6hp johnson dies at idle speed

You have us all puzzled over the carb. crxess has given you a picture of what should be there and a picture of a later type. I have given you a picture of an earlier type!

Perhaps you should go to THE PARTS CATALOG and have a ferret around.

Yes it has power-pack it is #11 in THIS Diagram The coils are #46 and the rectifier if you have one is #43

 

[spuds69]

Re: 1986 6hp johnson dies at idle speed

Thank you Vic S. for responding.Everything I've seen on the diagrams posted,points to the carb being pieced together with the wrong pieces.I truly feel that the dolt I bought the motor from cracked the bowl,replaced with wrong bowl,and passed his problems on to me.Live and learn.I'll replace the bowl with the correct one for my motor and post my results later on.Thank you again!

 

[iwombat]

Re: 1986 6hp johnson dies at idle speed

Ok, just for grins I went and located my spare '86 8hp carb (basically the same carb). In the side of the bowl is the connector for the primer. The main jet is incorporated into the pickup nozzle. There is no float bowl drain plug. I can post pictures if necessary.

 

[crxess]

Re: 1986 6hp johnson dies at idle speed

Well, now you now where the jet went.
Now you need to check it for trash/blockage. The jet is back in the hole and gas bypasses it to fill the bowl.
In other words you can have a clogged jet and still get gas into the carb.

 

[spuds69]

Re: 1986 6hp johnson dies at idle speed

Thank you for your response iwombat and crxess.Its too dark to attack it now,but belief me first thing after work tomorrow,me and this carb have a date!Thank you again,and I'll post my findings.