98 z this is a fresh rebuild 150 psi all cyl pto cyl only getting warm the others hot put new plugs doesent matter same thing. going to switch coils around tommorow see if the problem moves to another cyl. any suggestions as i am open i figure its maybe firing half the time need to get to the bottom of this quick been through carbs thats not it ???

Check the pos and neg wires that got to that coil. I had a broken one on my sled a few times and it did that. It was the PTO as well.
Start the sled and play with the small wires, it will fire and then not if you have a broken wire.

i will check that also . what else could cause this symptom after the rebuild and mods i did notice the pto not getting as hot but didnt pay alot of attention to it . but it didnt get any better and now there is a definatlly a problem.

How much of a rebuild? Just the top end? New plugs? If it follows the coil you have in narrowed down. If not then it might be the carb on that side or a bad seal somewhere. Have you checked the PTO main seal when it's running for a change in RPM?

no not yet but going at it tonight full force. would the cdi box or the stator have this effect on the motor?? electrical gremlins not one of my best subjects

Mine was doing that last spring and it was a bad coil. Try switching the spark plug wires and see if the new cylinder misses that you put the wire on and also if the bad cylinder starts working. This is how I determined I had a bad coil.

yes process of elimination, i would still check that carb out 1 more time. no fuel no firing had same prob with mine 2 seasons ago and was carb problem. would only fire once in awhile other 2 pipes very hot 1 just warm.

well coils check out. carbs couldent be more perfect. pto cyl plug cap not checking out so good on the multimeter god i hope thats it as i never get off that easy putting it back together tommorow havent checked the pto crank seal either im 99% sure its a spark issue. raw oil and fuel flying out of that pipe wish me luck as i dont have much of my own thanks ERIC

darn electrical gremlins

did it end up being the cheap fix? i sure hope luck was on your side this time! electrical gremlins are a pain in the arse!

bob

thanks for your concern bobbyo. yup! $3 plug cap resistor how many times do you get to fix one of these wonderfull mach zs for $3 answer not to many. thanks for the replies guys

how often? the answer is more like NEVER. it's never something simple with these Mach Z's

bob

Glad to hear you found a cheap fix!!