Trouble Starting and Running 70 Hp Johnson

[fsutim]

I have a 1978 Johnson 70HP on a boat that I bought from a guy about two weeks ago. The man said this boat had been sitting for about 2 years but had been mostly rebuilt 3 years ago including the carbs. The first time I took it out I was left stranded because the starter went out. I changed the brushes yesterday and now it is spinning great. Last night when I tested it, it would turn over faily easy on the first turn. This morning I took it out and it took a couple turns but it started. After stopping and going a couple times I tried to start it and it just kept spinning. You couldnt hear any spark. After getting towed back I came home and changed the spark plugs and it turned over fairly quickly but it would die out after a couple seconds. Then I would keep trying to turn it and nothing would happen for a while. WhenI came back to it the same thing happened, It started up but it puttered out after about 7 seconds. Then as I tried to start it again you could hear it almost catch but it wouldn't and then it would keep on spinning. Another thing I noticed today when it was working was as I accelerated it would tend to stall, until I gave it a while to warm up. I'm not sure If I need to adjust the carbs or whats wrong. Any ideas would be helpful. 2 trips out and 2 tows back to shore, not very fun.

 

[DJ]

Re: Trouble Starting and Running 70 Hp Johnson

fsutim,<br /><br />I believe you have a fuel/carb problem.<br /><br />Carburetors a can be finicky. Any fuel left in them, especially for two years, will foul them in a hurry.<br /><br />I think you're in for another carb. cleaning/rebuild.

 

[R.Johnson]

Re: Trouble Starting and Running 70 Hp Johnson

What do you mean by spinning? Starter spinning, and won't crank, or engine spinning, and won't start?

 

[OBJ]

Re: Trouble Starting and Running 70 Hp Johnson

fsutim....if the starter is staying engaged after the motor starts, drop a few drops of WD-40 on the bendix shaft and work it around a little. Also, it is possible the starter solenoid is staying engaged after you let lose the key. Sometimes a tap on the solenoid will shake it lose. If this is the problem, replace the solenoid.

 

[fsutim]

Re: Trouble Starting and Running 70 Hp Johnson

it will only continue to spin if it doen't turnover. If the motor turns over it will quickly die. And then I will try to turn it over and it will quickly catch and die. So does this mean it probably has something to do with the fuel, I've never adjusted an outboard carb but have adjusted an automotive carb. Does any one know where I can find information on this? I've looked at it a little bit but can't seem to find the mixture screws or idle screw. Also, is it normal after you prime the bulb a little bit and see fuel adding up in the filter, having the same amount of fuel in the filter after the motor has cranked. For instance, if I prime the bulb enough to have 3/4 of the filter full, when the engine dies the same 3/4 ammount will still be in the filter. Sorry if this all sounds hard to understand. Thanks for the help, Tim