wvmedic
Chief Petty Officer
- Joined
- Jun 3, 2008
- Messages
- 508
I have a 1973 2 cylinder 50 HP that is firing interment on the bottom cylinder, I have checked the firing before and didn?t notice this. I am getting a good blue spark and it is jumping 7/16 plus, but the bottom cylinder will on occasion stop throwing spark.
I noticed this after rebuilding the carbs, I thought there was a problem with them since I was getting good spark and had 120 psi on the top cylinder and 115 psi on the bottom.
After the rebuild the motor just wouldn?t throttle up right at WOT it seemed to bog quite a bit, so I rechecked compression and spark all seemed well.
Today I ran it on the muffs and pulled sparkplug wires, when I pulled the top plug wire the motor staled and when I pulled the bottom wire the motor stumbled and then smoothed back out so it didn?t make a huge change in the running. It was firing when I unplugged it though I had a small cut in the rubber on my pliers because I got a good jolt from it.
So from there I took it to the river same thing low power, WOT was real sluggish. I had the wife steer and I disconnected the choke rods, chocked the top carb and the motor would stall, did the same on the bottom carb and nothing happened.
Brought the boat back home rechecked compression it was the same, rechecked the spark and this is when I noticed that I had intermittent spark from the bottom cylinder.
Any suggestions on what the problem could be, or how to rule out or confirm what is going bad?
Thanks Jeff.
I noticed this after rebuilding the carbs, I thought there was a problem with them since I was getting good spark and had 120 psi on the top cylinder and 115 psi on the bottom.
After the rebuild the motor just wouldn?t throttle up right at WOT it seemed to bog quite a bit, so I rechecked compression and spark all seemed well.
Today I ran it on the muffs and pulled sparkplug wires, when I pulled the top plug wire the motor staled and when I pulled the bottom wire the motor stumbled and then smoothed back out so it didn?t make a huge change in the running. It was firing when I unplugged it though I had a small cut in the rubber on my pliers because I got a good jolt from it.
So from there I took it to the river same thing low power, WOT was real sluggish. I had the wife steer and I disconnected the choke rods, chocked the top carb and the motor would stall, did the same on the bottom carb and nothing happened.
Brought the boat back home rechecked compression it was the same, rechecked the spark and this is when I noticed that I had intermittent spark from the bottom cylinder.
Any suggestions on what the problem could be, or how to rule out or confirm what is going bad?
Thanks Jeff.
