1994 TWIN 135 hp black max V6's switchbox failure

[kramerpage]

My last trip out my port motor experienced a reduction of 1000 rpm at WOT. The marina checked compression and said it was great. They state they found a faulty switchbox. Replacement is 238.00 for part and 2hrs labor including troubleshooting. MY question is can a faulty switchbox reduce wot 1000 rpm. The motor still ran but had less power throughout the entire rpm range. Thank you for your help.

 

[Faztbullet]

YES A A LOSS OF A CYLINDER IS ABOUT 1000RPMS

 

[kramerpage]

OK Thank you. I have a spare parts motor. I think I'll go that route first. Again thanks

 

[kramerpage]

One more thing. I keep reading post that state they need to be replaced in pairs due to voltage bias. Is this a normal practice. My short shaft donor 135 has two but I can't wrap my head around it. Thank you

 

[Dukedog]

One more thing. I keep reading post that state they need to be replaced in pairs due to voltage bias. Is this a normal practice. My short shaft donor 135 has two but I can't wrap my head around it. Thank you

yep.. bad bias can lead to wrong "bad" switch box sometimes!!! check ebay.. new can be had for under a coupla hundred!.. any 7778A will be ok!