10R77A will not stay running without pulling out and pushing in the choke

[Havana Daydreamin]

I feel like I am beating my head against the wall. I have a 1977 Johnson 10R77A. It has sat for about 2 years without running. It would not start so I have done the following to get this thing back to life. The problem is that after I did all of the below I can get it to start on fast idle by turning the handle to fast and have the choke out and when it starts i can push in the choke right when it is about to die and it keeps running and then I pull it back out to add more fuel. I can keep it running that way but that is the only way. What can I check and do to make this thing work. Also the stop button is really rusty on the inside of the motor. If it is shorted out will I be able to do what i am doing to keep it running or would it not start at all.

1. I have good compression
2. I have good fuel and the fuel lines are clean
3. I replaced the fuel pump with a new one
4. I rebuilt the carb as per proper instruction
5. I have a new fuel line and bulb and all connections are tight

 

[dazk14]

Re: 10R77A will not stay running without pulling out and pushing in the choke

If indeed the carb is clean, going richer on the idle mixture adjustment should straighten out.

FYI- there are a few tiny idle holes in the carb bore (where throttle plate close) that MUST be clear, otherwise you won't be able to get fuel to it at idle.

Rotating the mixture adjustment counter-clockwise richens up the mixture.

Good luck.

Edit: Since a stop switch grounds out the spark - which you have - that is not causing your idle issue. When they corrode, they tend to do nothing - no connection to ground - so you have to pull the choke or plug wires to get it to stop.

SeaDog make a kill switch with landyard for about $15 that can be retro'd to that motor if you've got kids etc..

 

[Havana Daydreamin]

Re: 10R77A will not stay running without pulling out and pushing in the choke

Well I tried what you said and that did the trick. It runs great. I thought I tried it the first few times but I guess I did not turn the knob to the right spot. This time I started the mixture adjustment with it all the way lean and having the motor running by using the choke as I was doing before. Then made 1/4 turn increments until it started to run on its own. Then I fine tuned it when it was runing with out the choke.

My next step that I think I should do is get the motor in the water and adjust the idle mixture so it keeps the motor running at the slowest speed without dying and I think that should give me the best idle speed. My thought on that is that the lowest setting for idle mixture should be set at the lowest speed if that is set all of the speed above that should be good.

Also the stop switch looked little rough but it works like it should.

Thanks for you help.

 

[cr9c1]

Re: 10R77A will not stay running without pulling out and pushing in the choke

That mixture adjustment is for low speed only. The high speed jet has a fixed jet installed in it, which takes over when the speed gets high enough. You should be able to set it so it idles good and isn't rough and be good.

 

[OptsyEagle]

Re: 10R77A will not stay running without pulling out and pushing in the choke

Definitely set the carb properly. If it is too rich it will foul spark plugs and stick carbon to your cylinders and piston rings.

Once you have it running (without the choke) and warmed up put it in nuetral. Slow the idle to as slow as it can go without stalling. Slowly turn in (clock-wise) the idle adjustment 1/8 of a turn, at a time. Give it 5 to 10 seconds to respond. If it increases your idle, slow it down again with the throttle. Keep doing this until it coughs and looks like it is going to stall. Turn the idle 1/4 turn counter-clockwise and that is the perfect rich/lean setting. Place the knob so that the indicator is straight down in the middle of the range and you should never need to touch it again.