Ignition problem

[texan42]

Hey guys
I have a 1989 85 force, new plugs, fuel pump rebuilt, carbs cleaned and gone thru, primer bulb is good, start fine, the problem is that it runs as though it is missing intermediatly on a least one cyclinder and I believe it is the #1. Got out on the lake and when it is throtled up is runs rough like it is missing, then at full throtle it will all of a sudden "catch" and run great, hitting on all three, when you idle down it will do the same thing, run rough. Check coils and they seem to be firing except number one seems week. Number one CDI has had number two cylinder switched to the number two CDI, not sure if it is a CDI problem, weak coil, or maybe a trigger, any suggestion. I am leaning toward the CDI .
Thank You

 

[jerryjerry05]

Re: Ignition problem

Sounds like it could be water in the fuel.Check that first.Make sure there are no bad connections in the fuel line.Jerry

 

[texan42]

Re: Ignition problem

Thanks for the reply Jerry
Tank was drained and new fuel added , all fuel lines have been replaced.
Will check triggers tonight and work my way from there.

 

[john from md]

Re: Ignition problem

Texan42,

Swap the coils and see if the problem moves.

You may also have sticking check valves in the fuel pump. When they stick, they cause similar symtoms and the engine usually runs good at top end as the pump pressure is higher and overcomes the sticking.

Regards,

John

 

[texan42]

Re: Ignition problem

Thanks John
Fuel pump has been rebuilt, new valves installed. I believe I have found the problem, bad pair of wires from stator.
Thanks
Dennis

 

[texan42]

Re: Ignition problem

WTF, Replaced stator, replaced faulty CDI, #2 does not fire, swapped coil, swapped CDI, problem does not move, checked trigger ohms and they all read good, only thing left to change is the trigger( texan scratches head)
Compression on all three cylinders is 130. Was running on #2 before I changed stator but not correctly.

I will swap trigger tomorrow, after that I am lost as to what could be the problem.

 

[tjello327]

Re: Ignition problem

I am having similar problems with my 125hp. I have not had any replies on my post so I am still troubleshooting mine. I just bought a whole ignition system on e-bay and am going to try that when I get it.
My engine has no fire on #1 & #3. I changed around my stator leads to rule out the stator. I know that #2 & #4 spark so I put #2 stator lead to #3 terminal strip and it fired. This told me that the stator has no output on #3. I did the same thing for #1, still no spark. Swapped cdi boxes and still no spark. Swapped coils and still no spark. Disconnected kill wire, still nothing. Must be the trigger.
I have a used stator from a 85hp and put that on. I now have spark on #3 but not on #1 still. I have a couple spare cdi boxes I tried and still no spark on #1. The trigger is a new one from cdi the prior owner put on so I find it hard to believe its bad, but all the tests I have tried say it is bad.

Hope my story can help you
If anyone can help me please do!
Thanks!

 

[texan42]

Re: Ignition problem

Happy Days


The Force is with me.

Changed out new CDI with one I bought at a boat motor recycler, runs like a top, brand new CDI was bad.