I have a 1990 25 HP Mercury (0C26XXXX) that I need some help with. It is only firing on the top cylinder.
Mechanic friend thought it might be the switch box so I took another switch box from a parts motor I have and swapped the old one out (Part number 7452A15). Still the same ? Only firing on the top cylinder. Thought it might be one of the coils ? left one goes to the top cylinder and is working fine. Right coil goes to the bottom. So I tried switching the wires so that the right coil goes to the top cylinder and the left to the bottom. Now the Right coil works fine and the left one is not firing. Looks like my coils are both OK.
Still could be the switch box but it seems unlikely that both switch boxes failed to fire the bottom cylinder. Is there any way to troubleshoot the switch box? Don't have a DVA, just a multimeter
Are there any other parts that could cause the issue I?m seeing? I think the stator and trigger might, so I will need to check them to see if they?re OK. Resistance values I have for these are:
Trigger ? acceptable range 650-850
Stator ?
B/W wire to ground ?acceptable range 120-180
B/Y wire to ground ? acceptable range 3200-3800
B/W wire to B/Y wire ? acceptable range 3100-3700
Would appreciate any assistance on this particularly frustrating problem ? Thanks!
John
Mechanic friend thought it might be the switch box so I took another switch box from a parts motor I have and swapped the old one out (Part number 7452A15). Still the same ? Only firing on the top cylinder. Thought it might be one of the coils ? left one goes to the top cylinder and is working fine. Right coil goes to the bottom. So I tried switching the wires so that the right coil goes to the top cylinder and the left to the bottom. Now the Right coil works fine and the left one is not firing. Looks like my coils are both OK.
Still could be the switch box but it seems unlikely that both switch boxes failed to fire the bottom cylinder. Is there any way to troubleshoot the switch box? Don't have a DVA, just a multimeter
Are there any other parts that could cause the issue I?m seeing? I think the stator and trigger might, so I will need to check them to see if they?re OK. Resistance values I have for these are:
Trigger ? acceptable range 650-850
Stator ?
B/W wire to ground ?acceptable range 120-180
B/Y wire to ground ? acceptable range 3200-3800
B/W wire to B/Y wire ? acceptable range 3100-3700
Would appreciate any assistance on this particularly frustrating problem ? Thanks!
John