mercury switchbox Question

my 1994 mercury 60hp, does not appear to be providing power on the middle cylinder under load (WOT). IT suddenly dropped from its usual 5400 rpms under WOT to 4100 rpms.If I disconnect the plug wire to the midldle cylinder no difference in still about 4200 rpms, yet disconnecting either of the other two wires will cause it to barely run. Compression on all 3 cylinder is the same 120. I have changed plugs, and when the plug is out, it does to spark. I traded the coils around and still the middle cylinder does not seem to be giving power under load WOT. My question is can the switchbox deliver enough voltage to spark the plug, when its is out of the cylinder, but not enough to fire the plug under compression and a load?<br />Thanks,<br />Gary

Re: mercury switchbox Question

is the middle carb getting fuel.try spraying fuel into it.

Re: mercury switchbox Question

Just checked it, and yes it is getting fuel.<br />Gary

Re: mercury switchbox Question

Hey G. I had a similar prob with my '86 Merc 150. ODDD1 helped me out pointing me to the stator(see my april 14th post). All of the sudden one day she started to run sluggish and wouldn't go anywhere. I found weak spark on cyl 1, 3 & 5, but strong on 2, 4 & 6. When i pulled the wires off of 1,3 & 5, no change, but they would spark while out of he motor. Guess it wasn't strong enough to fire under pressure in the cylinder. The windings in the stator went bad. i repalced the stator ($150) as per ODDD1 and she runs perfect now. Not sure if this info will help in your situation with a different motor, but figured i'd pass it along. Good luck.<br /><br />- Jersey

Re: mercury switchbox Question

Ahoy, Gbarger. Have you confirmed that #2 has good compression? Stuck or broken rings can produce similar symptoms, as can bent or broken reeds. If you have a bad reed you should be getting fog spurts out of that carb. Not likely, but it costs nothing to check and might save you a few bucks.<br />Good Luck.<br />JB

Re: mercury switchbox Question

OOOOPS!! I just reread your post too late to edit mine. Sorry 'bout that.<br />JB

Re: mercury switchbox Question

thanks, for the advice and help,<br /> I did read the thread about your stator problem, Jersey. <br /> As I understand it, my problem is most likely the switchbox. The mecury 60hp motor only has 3 cylinders, and 1 switchbox. So if the Stator feeding my 1 switchbox was bad, then all 3 of my cylinders should be weak, not just one. If I am missing something here, please help and explain.<br /> I do appreciate the help thanks again,<br />Gary

Re: mercury switchbox Question

your logic is on the money, gary....if you have 1 cylinder tha wont pass a spark test [ 1/2" gap cranking] stator will be ok cause others have spark. If you swapped coils an that cyl still has no fire, the is either a trigger or switch box...triggers almost never fail on these, but switchboxes all the time.

Re: mercury switchbox Question

thx,<br /> I have it ordered. <br /><br />gary