Two cylinders firing at the same time

[BoatBuddy420]

I have a 1986 90 HP Johnson VRO. The #1 and #3 cylinders are firing at the same time. I indexed all cylinders on the flywheel and checked them all with a timing light. When i check the #3 cylinder the #1 mark is seen right next to the #3 mark and they are exactly 180 degrees from each other on the flywheel. I changed the flywheel, stator, timerbase, powerpacks, plug wires, and plugs. still no difference and running out of ideas...

 

[wjones]

Re: Two cylinders firing at the same time

Did you check to see if one plug wire is inducing a voltage in the one next to it? They may have to be rearranged in the loom so they are not next to each other. Possible.

 

[Rex]

Re: Two cylinders firing at the same time

Just make a car does the two wires come from the same coil if yes it's made to do that.<br />it does not hart the engine.<br />Rex a.

 

[Yepblaze]

Re: Two cylinders firing at the same time

My Suzuki has but one coil for two cylinders. One piston is up and firing whil another is down. As I believe the voltage travels from one wire through the gap of first plug, then through head, through gap of second plug, through the second plug wire, and back to the coil. This is very similar to late 80's GM cars.

 

[BoatBuddy420]

Re: Two cylinders firing at the same time

there are 4 coils, 1 for every cylinder.

 

[Joe Reeves]

Re: Two cylinders firing at the same time

Boatbuddy.... If 1 and 3 are firing at the same time, in all probability, the diode in the port powerpack (2 and 4)is faulty. Switch the powerpacks. If the problem now has changed to the port bank (2 & 4), replace what was the port powerpack.

 

[Dhadley]

Re: Two cylinders firing at the same time

Just for kicks, change the coils from one side to the other. I've seen this before but its very rare. I would switch the top two and then the bottom two. We may find it follows a coil.<br /><br />Keep us informed!

 

[BoatBuddy420]

Re: Two cylinders firing at the same time

I switched the powerpacks and the problem stayed the same.

 

[Dhadley]

Re: Two cylinders firing at the same time

What about the coils?<br /><br />Let us know!