mercury 115 in-line 6 firing help

[Javelin409B]

I have a 1985 mercury 115 with the brown stripes that the bottom cylinder is not firing. I bought a new coil for that cylinder with no change. Then put a new power pack on the bottom 3 cylinders with no change. So today,I put another new power pack on the top 3 cylinders just thinking that maybe both power packs being new,may have to work together,but still no change. Even put new spark plugs in it today thinking that might work. But still,the bottom cylinder is not firing. What else could it be???
Thanks,Jeff

[Six Four]

try putting the coil you took off bottom and changing it put with the one above it.

[kingsbiship]

You need to start at the start! Is it getting spark? Do you have compression equal to the rest? Reed valve in good shape? Bottom carb. feeds #5 and 6
So #5 is good? .... there's your start!

[Bruster]

I have a 1985 mercury 115 with the brown stripes that the bottom cylinder is not firing. I bought a new coil for that cylinder with no change. Then put a new power pack on the bottom 3 cylinders with no change. So today,I put another new power pack on the top 3 cylinders just thinking that maybe both power packs being new,may have to work together,but still no change. Even put new spark plugs in it today thinking that might work. But still,the bottom cylinder is not firing. What else could it be???
Thanks,Jeff

Not firing or no spark?

[Javelin409B]

no spark. Could it be the trigger?

[Raceman]

It's not the trigger. Is the coil ground clean? Check the wire from switchbox to lower coil with an Ohm meter.

[LightNBug]

It's not an open trigger coil if other 5 cylinders are firing. It could be a shorted trigger coil if other 5 are firing.

[Javelin409B]

I looked at the ground wires that were coming off each coil where the go over the the bottom of each powerpack,and on the coil where they connect,looked kind of corroded(old looking) took them off and scraped each one of them clean and when I hit the starter, number 6 fired like brand new again. Its amazing what a ground wire can cause. (lots of money on parts I didn`t need) but... Thats a lesson that i will never forget!!! and will be one of the first things that i will look for from now on.
Thank you guys for the help.
Jeff Brewer

[CrayzKirk]

I know that I've been guilty of thinking it's the most complicated thing when something is wrong. Typically, it's the simplest thing that is easily overlooked.

Good job!

Kirk S.