johnson tn-28 won't idle

[what66]

Hi I need help I just got my tn-28 johnson to run but it won't run below fast idle in fact it's wont run slow enought to put in nutral.<br />but it runs great at full speed . <br />any ideas .<br />it has new point and coils I'm going to get some new plugs today.<br />I have one more question on the carb just before the throttle plate there is a hole that goes throught the carb throte is this soposed to be there?<br />I have two of theses carbs on has a scew in it and the other doesn't but the screw does not look like it goes there.<br />I'm thinking that might be teh problem what do you think?

 

[WillyBWright]

Re: johnson tn-28 won't idle

Probably not the problem, but it shouldn't be there. I'd concentrate on the inside of the carb. Something inside is blocked. Another less attractive possibility is freeze damage. If water had collected in there and froze, it could've done damage you might not be able to see.

 

[Laddies]

Re: johnson tn-28 won't idle

the low speed adjustment is not even on the carb of a TN 28 it's the adj screw on the front of the crankcase, it should be at about 1/2 turn. with the engine running turn it in till it backfires and then richen it till it smoothes out--bob

 

[steelespike]

Re: johnson tn-28 won't idle

There are 2 mix adjustments on the motor one is the knob on the right top of the motor.the other is the little bent wire sort of dodad on the front of the crank case.Im not sure but I think the one on the front of the crankcase is the low speed but unfortunately I cant remember for sure.

 

[alcan]

Re: johnson tn-28 won't idle

Hi What<br /> The bent wire needle on the front of the block is your high speed adjust. The low speed adjust in on the wheel at the top of the tank along with the primer funtion. Push the wheel down for priming. Note it will prime thru the high speed needle. You should be able to hear it squirt. Be careful looking there with out safety glasses. It is a good way to get an eyeful of gas. One and one half turns out from lightly seated should get you started with the low speed adjust. I will need more info on the screw deal, I'm not sure what you are refering to. The problem sounds to me like you do not have the slow speed needle open enough. Can you get the motor to respond to the high speed needle at full throtle?

 

[what66]

Re: johnson tn-28 won't idle

yes it responds with the high speed needle but there is something strang the high speed was affected<br />by both of the ajustment screws both the dial and the bent wire.<br />the prime works fine but I have to have the throttle past start to start it I think it my be my carb.<br />I have another carb for it I'm going to clean it today and try that.

 

[what66]

Re: johnson tn-28 won't idle

It runs great now that screw was the problem once I took it out and ajusted the jets it runs fine now that you all for the help.