starting 1972 johnson 4 hp.

[mikeaga]

I just got a 4 hp Johnson. It tries to start, runs for a few seconds and quits. I do not know what to set the mixture nob or the speed nob or the choke and throttle. Any help would be appreciated. Thanks.

 

[Daviet]

Re: starting 1972 johnson 4 hp.

Got two needle valves?
Top one is the low speed needle, 3/4 turn out from lightly seated.
Bottom one is the high speed, 1 1/4 turn out from lightly seated.
You will have to fine tune both needle valves with the boat in the water under load.
On a cold start, pull the choke all the way out, push it in when the engine starts.
The throttle should be about 1/3 the open on a cold start and then slow it down as the engine warms up.