ignition question

[lyncraft_mechanic]

just recently i have lost spark to my bottom two cylinders on my 1989 Johnson gt100HP outboard. i tried swapping coils and get the same result! thinking it could have been the power pak i purchased a new one and installed it but i still have no spark on the bottom two cylinders..... so what could it be? the timer base or the stator? Im thinking its the timer base myself. thanks for your time and any suggestions would be helpful at this point

 

[lyncraft_mechanic]

Re: ignition question

okay finally fixed the spark issue and have the motor running great on muffs in the yard. tonight i took it to the launch and the motor runs really good but when i try to put it in gear it stalls every time what could be causing this?

 

[jonesg]

Re: ignition question

If theres a shift assist switch ?, unplug it.

Otherwise I'd say carbs are clogged, try hitting the choke when you shift, if it keeps running take it home and rebuild the carbs with new kits, don't run it as is.

 

[lyncraft_mechanic]

Re: ignition question

I just totally rebuilt the engine (carbs included) because number 1 cylinder swallowed a ring, i was lucky that there wasnt hardly any damage done. the one thing i did do is convert from VRO to premix, not sure if that is contributing to the problem or not? i did try choking the engine while shifting and it doesnt help! i guess i can pull the carbs back off and inspect them but why would it run great on muffs(will run great in gear while on muffs)and in the water until it was shifted into gear? could it have something to do with the timing? anyone know what the timing should be at an idle? any help is greatly appreciated.

 

[lyncraft_mechanic]

Re: ignition question

bump

 

[emdsapmgr]

Re: ignition question

You may have the idle set too low. The idle should be set to 650-750 rpm when the engine is idling in gear, at resting normal level in the water. You don't need to worry about the specific idle timing, per se: set the idle to a specific rpm, regardless of whether the idle timing is 4, 5 or 6 degrees.

 

[lyncraft_mechanic]

Re: ignition question

well i finally gave up and brought the boat over to a local marina and had a mechanic look at the outboard. the reason the engine wouldnt stay running in gear is because the idle was a little low but also the bottom two cylinders are not firing correctly if at all. i have spark to all cylinders but the bottom two are not igniting the fuel so we put a new set of plugs in and when that did not correct the problem i was told that it was more than likley some bad reed valves are causing the problem. i ordered all the parts and they should be here wednesday, i will post the results!!!!!

 

[Silvertip]

Re: ignition question

Idle mixture and idle speed adjustments must always be done with the engine IN the water, not on muffs. Lack of exhaust back pressure when running on muffs makes adjustments always turn out lean.