Author Topic: Tachometer Quit (MD11C)  (Read 9372 times)

My Cyn

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Tachometer Quit (MD11C)
« on: September 04, 2012, 08:51:18 PM »
Hi Folks,

The tachometer on My Cyn stopped working during my last trip on the water. The needle is dead. Other than that, the MD11C runs as usual.

Has anyone out there experienced a similar failure?

Cheers!

Bill
« Last Edit: July 22, 2019, 09:33:29 AM by admin »

Libations Too

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Re: Tachometer Quit
« Reply #1 on: September 12, 2012, 12:49:51 PM »
Hi Bill,

No similar problem here but a quick review of the Volvo Penta Workshop Manual (link on this website home page) shows that the tachometer works via a speed sending unit located on the starboard side of the engine (see page 8 ). Wires run to the tachometer (see wiring diagram page 35). The wiring diagram also provides wire color code to help find the wires.

My understanding is that the sending unit sends a current (or pulsed current) to the meter. So a multi meter test at the sending unit while the engine is running should show some current. If it does, then test again at the meter to see if the same current reading is seen there. If not it is probably a wiring or connection problem.

My first instinct was to tell you to confirm that the alternator belt and alternator were working properly. But then I remembered that when my alternator was inoperable the tach still worked. I'd start by confirming good connections at both ends of the wiring, then do the current test with the engine running.

Hope this helps,
Richard
Richard

rbrtfeld

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Re: Tachometer Quit
« Reply #2 on: September 13, 2012, 06:06:34 PM »
I have had my Tach do the same thing a couple of times on my Volvo MD11. Find the wire that plugs into the sending unit on the motor and I will bet it is off or has a bad connection. Mine slipped off and I plugged it back on to the sending unit and the tach worked fine again. I put a piece of Electical tape around the connector to make sure it did not slip off again. Good luck

My Cyn

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Re: Tachometer Quit
« Reply #3 on: April 21, 2013, 10:21:25 PM »
Hi Guys!

I spent some quality time with the tachometer this weekend. The wiring between the sending unit and the gauge in the cockpit was in good shape and showed to be continuous when checked with a multimeter.

The sending unit checked out good:  it sent out a consistent ~0.6 volt AC signal at idle, and voltage increased as I added throttle. Good news, as a replacement is $$$.

A quick check at a few local ship-chandleries told me that the particular gauge was no longer available.

Interested if anyone has replaced the tach guage on their Pearson 323.

Best,

Bill

Rusty Pelican

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Re: Tachometer Quit
« Reply #4 on: August 06, 2018, 07:28:48 AM »
I have a working spare Tach

Rusty Pelican

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Re: Tachometer Quit
« Reply #5 on: August 06, 2018, 07:49:58 AM »
Thanks guys for the quick response.

The alternator works fine, the connections over all and at the sender are fine. Connections are good
The sender is not putting out any juice.
The crux of my problem is what piece of hardware on the Sender assembly do I need to replace.
It's a funny looking assembly.
I can get a new sender, not sure that will do the trick 

Bill1188

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Re: Tachometer Quit
« Reply #6 on: August 06, 2018, 06:11:04 PM »
I have a complete MD 11 and instrument panel in my garage. Let me know what you need.

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Re: Tachometer Quit
« Reply #7 on: August 06, 2018, 10:05:23 PM »
Thanks, but I have a full panel as well for spares.