89 Mariner 50hp firing on 2/3 cylinders

[davemillertime]

I just bought a 1989 Mariner 50hp & The motor when its cold will only fire on 2of 3 cylinders. last nite I was out and it took about 10min and, then the third plug kicked in. Then i shut the motor off for a while and when I started it again the third cylinder wasnt firing AGAIN . so i motored to the launch and as i got to the launch i could hear the third plug trying to fire again .????????????????

 

[Laddies]

Re: 89 Mariner 50hp firing on 2/3 cylinders

Your stater is good as it's furnishing power, the trigger is 3 windings which seldon repair them selves and normal get worst with heat so that leaves the switch box would you like a test for the system?

 

[davemillertime]

Re: 89 Mariner 50hp firing on 2/3 cylinders

Your stater is good as it's furnishing power, the trigger is 3 windings which seldon repair them selves and normal get worst with heat so that leaves the switch box would you like a test for the system?

Sure Ill take any help I can I did change the plugs today and havent had a chance to run it. I will be back out on thursday , Also I had a friend with the same trouble he said someone messed with ""the spark advance screw"" just wondering if that could be the cause

 

[davemillertime]

Re: 89 Mariner 50hp firing on 2/3 cylinders

Can anyone tell me how to test the switch box? also atest on the coil

 

[Laddies]

Re: 89 Mariner 50hp firing on 2/3 cylinders

Without a DVA you can not check a switch box and then only by checking input and output voltage but you can test the rest of the system and if it's OK the problem is the box.