No more synchro, no more tach

[Seas the Moment]

I have 1979 58' with 8V92TIs, microcontroller, and synchronizer.

I was headed to an anchorage on St Johns last week... 1300 RPM, synchros on and suddenly throttle jumped up, I pulled both back to nuetral, port tach was at 0, strbd at idle RPMs. I thought the port engine shut down. Nope. I was able to manually throttle both engines, but no more auto synchro and no port tach reading. All other gauges working properly. Syncro is mounted in port ER. So I assume it is the port engine is the master. Ii it connected via manual cable? Could that cable have snapped?

Thanks!

 

[GJH]

Is the synchro a part of the Microcontroller system?

 

[MikeP]

From your description, I'd concur that the drive cable from the port engine to the tach has failed. It's possible that the cable itself broke but not very likely. Probably the fitting on one of the ends of the cable has worn (rounded off).

 

[Seas the Moment]

No George, the synchro is a Glendenning.

 

[OBXTucker]

You could have some cable strands that are bound up inside te Glenndining box. Open it up and take a look.
I had this happen a couple of years ago (exact same symptoms) and it ended up that the cable inside the box was a mess. New cable and all was well.

 

[Genesis]

There's a drive adapter on the back of the engine where the cable comes out that goes to the Glendinning, and then the tach sender on the front of the Glendinning, if your boat is like mine was.

The drive adapter has a worm gear in it and a little stub shaft that engages the engine. If it gets sloppy and binds up the stub shaft will shear off.

Check there; if that's what happened replacing the stub shaft will not fix it as it will bind again. That little adapter is a wee bit expensive too for what it is.

 

[GJH]

I had the issue Karl describes. Glendinning sells the adapters. The new ones have a zerk fitting for occasional lubrication. I went ahead and replace them both. To trouble shoot, we started at the synchro and worked our way back, the end of the cable going into the synchro wasn't moving, when we pulled the other end off the adapter at the engine and turned it, the synchro end turned, then noted looking into the end of the adapter it didn't turn with the engine at idle. Easy fix from there.

 

[bobk]

Had the same symptoms two years ago. It was the drive adapter on the master engine. I was 50 miles from Glendining. They made one up for me overnight and I picked it up the following morning.

Thx for the reminder to grease it.

Bobk

 

[Seas the Moment]

Thanks! I'm on it! Once again, this forum and the level of help and experience shared is reason enough to own nothing other than a Hatt!

 

[Bob Bradley]

And be sure hasn't simply fallen out of the receptacle on the transmission. I have one that only stays in place if I use wire zip ties.