Shifting problems

[weaz14]

I have a 1989 5.8 omc cobra and runs great other then the fact that when it's running and I try to take it to neutral from forward position the shifter just locks up. And I can't get it to freeze up when on land only seems to do it on water. No grinding or anything like that just freezes up but I can shut the engine down and it will shift fine. Has the red (so called new) lower drive cable on it so anyone else have this problem!

 

[weaz14]

And it's a 2150 Bayliner Capri with omc drive

 

[airdvr1227]

Re: Shifting problems

I'd start with replacing the shifter cables.

 

[Bridar]

Re: Shifting problems

It sounds like your shift interrupt system may not be working properly. The engine RPM needs to be between 450 and 600 RPM before the thrust from the propeller will be low enough to allow the clutch dogs to release.

I suggest you read the following thread; http://forums.iboats.com/showthread.php?p=1930449#post1930449

 

[weaz14]

Yes I'm going to replace my cables anyway they are a little stiff and appreciate the post on the switch. Will look at that as soon as I pull it out from winter (sucks when it's all wrapped up cant work on it! Annoying)

 

[subcrx]

Re: Shifting problems

I had this problem when I first purchased my boat. It took alot of research and tricks to fix this. First thing is your idle has to be low. about 550 for a small block. Lower the idle the better it will release. The shift interrupter helps by cutting out some cylinders to temporarily drop the idle to make smoother shifting. If you have an electron ignition conversion the shift interrupter will not work, There is a diode fix for that which you can do yourself and the parts can be found at radio shack pretty cheap. See here for the diagram. http://www.pertronix.com/support/tips/pdf/diodefix.pdf hope that helps. Do not attempt to replace the shifter cables yourself! You will open up a whole new can of worms.

 

[weaz14]

Thanks ya definitely not trying to replace shifter cables and I'm hoping it's just the cutoff switch is bad or bad connection cause now that I thought about it I could not hear motor drop rpms when trying to shift but for me it's a waiting game now due the weather only if I could built a heated garage off the house (but if I mention that to the wife she might just drill holes in the boat so I'll just wait ha)

 

[Don S]

Re: Shifting problems

The switch is doing what it's supposed to do, your problem is something in the shift system causing excessive resistance and engaging the shift interrupt switch. There is a 90% or better chance that it's the cable, and it's a common problem.
Perhaps you need to understand the system a bit better, here is a look at the merc system that does the same thing. The OMC setup causes the engine to miss with an electronic shift assist module (ESA) but the switches and the reasons behind the system are the same. Have a look at this thread. http://forums.iboats.com/showthread.php?p=1930449#post1930449