1994 9.9 narrowing down no spark in 1 hole

[rrw]

Hi, my Johnson 9.9 is only sparking on the top plug, it will occasionally fire on both but only briefly.I switched coils around, didn't change, tried a different power pack, didn't change, switched the leads from the power pack at the coils and that switched it to the top being dead. Does this narrow it down to one failed component? If not, what are the next steps to peruse? Thank you for any help, Ryan

 

[AlTn]

Re: 1994 9.9 narrowing down no spark in 1 hole

throw out the results from a different pp and it points to the original pp being the culprit. With the exception of a pinched or bare spot in a wire nothing under the f/w will result in a spark on only 1 cylinder on a 2 cylinder cd ignition. Think of the pp as having 2 switching circuits through it. When the route for one or both gets "iffy" or completely broken then little to no voltage goes to the coil(s) for that circuit(s). The fact that your coil can deliver a spark from either the top or bottom position rules it out as suspect. I'd suggest cleaning the ground wires and attaching points as well as using some electical cleaner or rubbing alcohol to clean the male and female fittings within the amphenol plugs and see if that affects the spark. If not, that pp looks like the suspect.

 

[rrw]

Re: 1994 9.9 narrowing down no spark in 1 hole

Ok thank you. I also should have mentioned that the test power pack is a new one but from a 1988 40 horse I had. You answered my biggest question on whether or not it could be something under the flywheel, will check connections, grounds, wires, thanks! Ryan

 

[rrw]

Re: 1994 9.9 narrowing down no spark in 1 hole

Hi, ok, well after digging into this a little more its even more confusing. The motor will start and run and I can usually keep it running if i play with the throttle and primer solenoid. If I let it die ill check for spark, one is usually dead, ill leave it unhooked, and fire it up, it runs the same as when its plugged in. But the dead wire isn't always the bottom one, it is occasionally the top . Usually if I let the motor sit awhile both plugs have spark, but it looks weak and still runs like crap. Being that I've ruled out the powerpack and coils what else comes to mind? Is there anything under the flywheel to cause this strange erratic spark? I bought this motor not hearing it run. I cleaned the carb out and it fired right up and seemed to run good in the shop, I installed it on the boat, it sat for about a month now runs like crap. Help please!

 

[AlTn]

Re: 1994 9.9 narrowing down no spark in 1 hole

what you are describing are pp symptoms....the pp from the 1988 40 hp. isn't the same as the one for a 1994 9.9 hp.

 

[rrw]

Re: 1994 9.9 narrowing down no spark in 1 hole

Thanks for replying again. I noticed the part # was different but it runs the same way with either pp. I guess I can try to find a used one from a 9.9.

 

[rrw]

Re: 1994 9.9 narrowing down no spark in 1 hole

Also, will the motor run if I buy and install 2 inline spark testers? That way I could watch what's going on. Thanks.

 

[AlTn]

Re: 1994 9.9 narrowing down no spark in 1 hole

dunno...never tried it...I use an inductive timing light

 

[rrw]

Re: 1994 9.9 narrowing down no spark in 1 hole

Ok, my buddy has one, ill try that. What are all the wires from the stator to pp for? Is only one wire the timing signal? Thanls

 

[AlTn]

Re: 1994 9.9 narrowing down no spark in 1 hole

b and c carry the trigger signal....it comes in on one and returns on the other depending on the polarity...if my thinking is right

 

[rrw]

Re: 1994 9.9 narrowing down no spark in 1 hole

Ok thanks for all the help! Pp are cheaper than I was thinking, ill just get a new sierra off eBay and call it good. Thanks again!