More help needed 1989 omc 140 seadrive

[Cdnpokerface]

Okay first off thank you for all of the help in my other thread. I've sorted some issues out but I'm still having one I can't wrap my head around.

Here are the details

I'm using the engines in Ontario vanada so out water temp is approx 48 degrees

My starboard engine is running good the port has been giving me some issues.

My issue is it starts and idles fairly ok for a few mins then idles down low sometimes comes back to normal and then will die.

I have replaced both thermostats as they were both toast and engine was running very cold.

All carbs have been rebuilt

Compression test done all cyls between 120-125

Replaced fuel water seperator

Replaced spark plugs and coils.

Replaced voltage regulator


I have determined when I unplug coils on cyl 1 & 3 nothing changes in the way the motor runs. I have checked spark and it is bright blue and jumps 7/16 gap with no issues also the plugs on 1&4 look as tho they are sparking just not clean. I also tried swapping the plug wires between 1&3 i case something was mixed up in the cdi wiring but when I do that the engine doesn't want to start at all


The carbs are calling for fuel and getting fuel delivered when I cover the fronts of them.

The only things I haven't done is check dva values on the ignition parts yet

Any advice would be greatly appreciated

 

[boobie]

Are you covering the carb throats for cylinders 1&3 and the motor picks up??

 

[Cdnpokerface]

I went back to boat and checked resistance values. Everything matched up with the specs from cdi trouble shooting guide except the two wires that come from the stator brown and brown Orange the value was far below the value they state. .941 was what I got and the book says 430-650

 

[boobie]

Hard to believe the stator is bad if the spark will jump a 7/16" open air gap.

 

[Cdnpokerface]

I agree. I thought if stator was bad if have no spark at all... I def have spark, fuel and compression but when I remove those two wires the engine runs no different!!

Would a bad power back cause this?

Bad timing?

Bad reeds?

Where else should I look so frustrated!

 

[Bosunsmate]

I have determined when I unplug coils on cyl 1 & 3 nothing changes in the way the motor runs. I have checked spark and it is bright blue and jumps 7/16 gap with no issues also the plugs on 1&4 look as tho they are sparking just not clean. I also tried swapping the plug wires between 1&3 i case something was mixed up in the cdi wiring but when I do that the engine doesn't want to start at all

What does each plug look like?
Black, oily, grey, white, purple, pink?

 

[Cdnpokerface]

#3 is is very sooty looking. 1 is the same but not as bad and 2&4 look pretty normal maybe not perfect but definitely better

 

[tblshur]

might try disconnecting the yellow black shut down wires from power packs:joyous:

 

[Cdnpokerface]

Ok I will try this. What would be causing an issue there?

 

[Bosunsmate]

whats temp like now?
Is it able to get to wot ok? Is the only problem that itl die at idle after a while?

 

[Cdnpokerface]

It doesn't die at throttle but I can not obtain full rpm., my friend is pointing me towards reeds... Is it possible to inspect reads with an inspection camera? So I don't have to pull manifolds off?

 

[Bosunsmate]

It doesn't die at throttle but I can not obtain full rpm., my friend is pointing me towards reeds... Is it possible to inspect reads with an inspection camera? So I don't have to pull manifolds off?

depends how good your camera is.
has this motor got a vro?

 

[Cdnpokerface]

Ok it's fixed! I tested dva output this morning between trigger and power pack. And had a weird value ... So I disconnected and it went away. Replaced power pack and seems to run beautiful now. Lesson of the week don't even try and trouble shoot these ignition systems without a dva!!!

 

[boobie]

Grandpa always said, " you learn something new every day ".