Tach - Glendenning

[Freestyle]

For purposes of discussion, 1986 54 MY with 8v92TA's. Assume I am an idiot and mechanically unskilled.

Port tachs stopped working at both helm stations. Glendenning quit engaging at same time. I am guessing failure at sender.

Where is the sender and what should I look for?

What type of tech do I call to fix? Detroit Diesel? Glenndenning? Other? Boat is in Tampa.

Would installing Flo Scans, digital tachs, or an upgrade by necessity fix the problem?

What is the estimated purchase and install cost for this route?

Thank you for your thoughts and assistance.

Bruce

Freestyle
1986 62 CPMY (54MY with ext. cockpit)
Tampa

 

[Briankinley2004]

I would call Glendenning. They are very helpful and got mine going right off the bat. Sounds like you are on the right track for a sensor based on this link.

https://www.glendinningprods.com/wp...onizer_-_Troubleshooting.v1.pdf?4cf23d&4cf23d

 

[racclarkson@gmail.com]

Not a great picture, but here's your sender.



There are, as I recall, two very small gauge leads attached. They are delicate. May be a good starting point.

 

[Photolomy]

I thought glendenning uses mechanical drive cables between the engines and the unit. Senders would be far too inaccurate to get an exact match of RPM. A single problem may still be causing both symptoms, but it wouldn't be the sender.

 

[racclarkson@gmail.com]

I thought glendenning uses mechanical drive cables between the engines and the unit. Senders would be far too inaccurate to get an exact match of RPM. A single problem may still be causing both symptoms, but it wouldn't be the sender.

Throttle and shifters are cables. The RPM input from the motors is an electronic takeoff from the motor’s gear driven tach drive.

 

[Photolomy]

Throttle and shifters are cables. The RPM input from the motors is an electronic takeoff from the motor’s gear driven tach drive.

You are correct. I took another look at lunch and the tach input is electrical, not mechanical.

 

[tonytrakovich]

My boat had 1292s but it had a mechanical drive cable between the engine and the glendinning. The tach sender was on the glendinning. I had the same problem. It was the drive cable and 90 deg. adapter on the engine. Lauderdale Speedometer made me a new cable and adapter while I waited. Problem fixed.

 

[dottieshusband]

The tachometers and glendenning synchronizer are driven by a small pigtail coming off the back of your blower drive. The square drive from the blower drive shaft enters a tachometer pickup, and glendenning pickup. Hopefully, it's a problem in the pickup unit. The drive pigtail can breakdown, and that's a serious issue because it can put metal into the engine. On my engine, it's on the port engine. Easy fix. 2 nuts hold on the pickup unit, and the blower shaft is retained by a c clip, and just slides out. The Glendenning folks have repair parts, but you'll need to know your rotation ratio.

 

[SKYCHENEY]

My boat had 1292s but it had a mechanical drive cable between the engine and the glendinning. The tach sender was on the glendinning. I had the same problem. It was the drive cable and 90 deg. adapter on the engine. Lauderdale Speedometer made me a new cable and adapter while I waited. Problem fixed.

This is the way my boat is set up as well.

 

[osprey]

My tach generator is fitted on a small 90 degree gear box installed on the back of the transmission pump. a cable drive then delivers rpm to the glendenning synchronizer. The tack generator can also be put on the other end of the cable going into the synchronizer. Two wires send impulse signal to tach gage.
Pete

 

[davidwigler]

My boat had 1292s but it had a mechanical drive cable between the engine and the glendinning. The tach sender was on the glendinning. I had the same problem. It was the drive cable and 90 deg. adapter on the engine. Lauderdale Speedometer made me a new cable and adapter while I waited. Problem fixed.

My 8v71TIs are set up this way and the 90 deg. adapter is loose. Should it be tightened by tightening the collar? It looks like about a 1.5” nut. Is it a diy project to remove, check the gear and replace?

 

[davidwigler]

The tachometers and glendenning synchronizer are driven by a small pigtail coming off the back of your blower drive. The square drive from the blower drive shaft enters a tachometer pickup, and glendenning pickup. Hopefully, it's a problem in the pickup unit. The drive pigtail can breakdown, and that's a serious issue because it can put metal into the engine. On my engine, it's on the port engine. Easy fix. 2 nuts hold on the pickup unit, and the blower shaft is retained by a c clip, and just slides out. The Glendenning folks have repair parts, but you'll need to know your rotation ratio.

Sorry I copied the wrong post. Mine are set up like this on the blower drive.

 

[HahnR]

My tach generator is fitted on a small 90 degree gear box installed on the back of the transmission pump. a cable drive then delivers rpm to the glendenning synchronizer. The tack generator can also be put on the other end of the cable going into the synchronizer. Two wires send impulse signal to tach gage.
Pete

Mine is this exact same way. Today we did sea trials after having to get the starboard engine rebuilt - again. The starboard tach no longer works at either helm. I have verified the cable is turning entering the sychronizer. Is there power supposed to be going to the sending unit on the sychronizer, and if so where does it come from? Did not read any from either wire. I plan to troubleshoot this further this weekend and would appreciate any suggestions anyone may have. It worked before we did the rebuild so I'm thinking something got disturbed