Hi gang,
Issue with my 90 Johnson any insight greatly appreciated!!
Carbs were gone through and cleaned out along with new gaskets this winter. Tach was dead so I swapped rectifiers (had another used but good one) and tach functionality has returned. Pulled compression a month ago (do it every spring) and it was 120psi on all 4.
When I fired her up a month ago and idled her on the hose I thought all 4 holes were firing. However, this weekend when I cranked the motor it sounded a bit off. On the hose, I pulled the plug wires one-by-one. 3 of the 4 plug wires, when pulled caused a major RPM drop / near stall. 4th (top stbd) wire when pulled causes no change.
I don't have a spark tester however I did pull the plug and wire and had my son crank as I held the plug against engine ground and I'm getting some spark. That plug also shocked me through the boot (not sure if arcing??).
Tried swapping coils -- no change.
Tried swapping plug wires -- no change.
Tried swapping plugs -- no change.
Motor has only idled on the hose a few times since a month ago when I pulled compression. I can't imagine I somehow lost compression / blew the hole? But I will re-check (don't have a gauge will have to borrow). Also skeptical it's starving for fuel but I can go through that cylinder's carb again and check -- do these carbs cross-feed (ie, top stbd cylinder fed by top port carb)?
Stbd tan temp wire is somewhat close to coil wire however I can't re-route it further away without cutting/splicing it and while I don't make a habit of winding a motor up on the hose it will rev past 2500 so not thinking this is a SLOW issue. But I could be wrong?
My question is, can weak / intermittent spark cause a situation where I am getting some spark but not enough to efficiently produce power in a cylinder? Has anyone ever seen something like this? If so, is a bad pack more likely than a bad stator? I don't have a DVA.
Any other ideas? Thank you!!
Issue with my 90 Johnson any insight greatly appreciated!!
Carbs were gone through and cleaned out along with new gaskets this winter. Tach was dead so I swapped rectifiers (had another used but good one) and tach functionality has returned. Pulled compression a month ago (do it every spring) and it was 120psi on all 4.
When I fired her up a month ago and idled her on the hose I thought all 4 holes were firing. However, this weekend when I cranked the motor it sounded a bit off. On the hose, I pulled the plug wires one-by-one. 3 of the 4 plug wires, when pulled caused a major RPM drop / near stall. 4th (top stbd) wire when pulled causes no change.
I don't have a spark tester however I did pull the plug and wire and had my son crank as I held the plug against engine ground and I'm getting some spark. That plug also shocked me through the boot (not sure if arcing??).
Tried swapping coils -- no change.
Tried swapping plug wires -- no change.
Tried swapping plugs -- no change.
Motor has only idled on the hose a few times since a month ago when I pulled compression. I can't imagine I somehow lost compression / blew the hole? But I will re-check (don't have a gauge will have to borrow). Also skeptical it's starving for fuel but I can go through that cylinder's carb again and check -- do these carbs cross-feed (ie, top stbd cylinder fed by top port carb)?
Stbd tan temp wire is somewhat close to coil wire however I can't re-route it further away without cutting/splicing it and while I don't make a habit of winding a motor up on the hose it will rev past 2500 so not thinking this is a SLOW issue. But I could be wrong?
My question is, can weak / intermittent spark cause a situation where I am getting some spark but not enough to efficiently produce power in a cylinder? Has anyone ever seen something like this? If so, is a bad pack more likely than a bad stator? I don't have a DVA.
Any other ideas? Thank you!!
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