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Outboard Johnson 70 starting issues

R

rdopson

New member
Hello all!

First off, I would like state for the record that I know very little about outboard motors.* So, here is my problem.* I was out on the lake a couple of weeks ago and could not get my motor started.* Under the hood, I found a little red valve that, when turned, dumps all my fuel back into the gas tank.* It may be just me hearing things, but it also sounds like air being dumped as well.* I've asked around a bit and vapor locking is the response I seem to get the most.* Could this be what it is?* If so, how do I fix it so I don't have to play around with what I believe to be the intake manifold every time I want to use the outboard?* I know that my fuel mixture is good, with a ratio of 4:1 , and I only use premium unleaded.* I had read somewhere that I shouldn't use high octane gasoline, but everyone I talked to said to use premium with no ethanol, so I don't believe this is the problem. My motor details are:

Make: Johnson
Model: J70TLCUR
Year: 1987

Any help or useful advice would be greatly appreciated as this problem is very annoying.* Thanks!
 
The little red valve is the electric primer that is used for starting the motor ( takes the place of choke flappers )--------If operating that dumps fuel into the tank there is a HUGE problem with your fuel system !!!---I think it is impossible.---------What is this ratio of 4:1 all about, your gas oil mixture should be 50:1 on that motor.--------------How long have you owned the motor ?-------------Explain how you are trying to start this motor in some detail , as it seems you may be doing something wrong !
 
I've only owned the motor for a little over a month. The guy I bought it from told me to use 4 oz. of oil to 1 gallon of gasoline, and since it is a 6 gallon tank, 24 oz. to 6 gallons. That is where I got the 4:1 from. So, for starting the motor, I'd get to the boat landing, undo all the straps to launch the boat, prime the bulb until full, and just back it in. When I tried to start it and it wouldn't turn over. I tried with and without choke and nothing happened, same with the fast idle. I probably should have mentioned earlier that the motor is console controlled. This is when I discovered that little red knob. I'm not entirely sure it is actually dumping fuel back to the tank, I'm just making that assumption since, after playing with the knob and having to reprime it, that is where the fuel is going. When I turn that knob, I can hear a hiss that sounds kind of like a mixture of water running through pipes in your house and air being pumped into a compressor tank. Sorry, that's the best description I can come up with. After repriming it, the motor will start after two or three tries. So, since you mentioned the electric primer, could this part be going bad, or is that little knob just not adjusted properly?
 
That is quite a bit of extra oil in there.
Should be 16 oz. to 6 gallons.
Hopefully raceone will straighten out the starting issue.
 
By operating the red lever you are doing the same as when you push the key in.---You are putting fuel into the intake manifold for starting.-------The red lever should be parallel to the primer valve body for electric operation.---------------To start you operate the control box and advance it in throttle only mode.--------prime the bulb.-----Push key in while cranking the motor over.----When motor starts push key in as needed till motor warms up.---Do not let motor wind up too much in nuetral.
 
These are all really great ideas, thanks all! I went looking for spark plugs tonight, but walmart didn't have any. Will try Autozone tomorrow. Will also try the different fuel mixture as well. So, next question. If that little red knob is just the manual version of pushing the key in, and it doesn't work with the key, but works with the knob, wouldn't that mean the someting is wrong somewhere in between the primer solenoid and the push-to-choke?
 
Sorry for the delayed response, was a bit under the weather. Ordered the spark plugs today and as soon as I get time, I will test the solenoid.
 
Well, I have awesome news. Turns out, the primer solenoid was stuck. I fiddled with it yesterday and got it to work. Also changed the spark plugs, now it runs like a dream. Thanks all for all your help!
 
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