Hour meter digits disappeared

[Ostinato]

I have two engines with tachs that have built in lcd hour meters. The tachs and the built in night lighting works fine but you can't see the lcd hour meter display. If you look at one of them from an oblique angle you can barely make out the digits and it seems to be accurate. I've tried a spare tach and it is doing the same thing. Any ideas about what causes this, and how to fix it?.

[2Wind]

Some are repairable e.g. VDO guages in Yanmars. Had mine repaired for about $150 each - not cheap but included new lamps and perspex face. Google search for instrument repairs in your area.

[jaybird1111]

Google here for volvo tach repair... the gauges are VDO. It is likely the ribbon cable needs cleaning. There is a detailed fix thread here at CF

[a64pilot]

He said he tried a spare tach and it's doing the same thing, unless the spare has the same malfunction, it's not the tach, I'd sure try cleaning the cable, with a pencil eraser if it will get in there and with contact cleaner if it won't. If not that, then what does the other end of the cable connect to?
Does anyone else coat every electrical connection with silicone grease? It's just one of those OCD things I do.

[jstevens]

The loss of the hour meter LCD display seems to be a common problem with the VDO tach instrument supplied by Yanmar. Mine went out several years ago. I looked at the solution offered on another CF thread (search; "Yanmar hour meter"), but it does not apply to my instrument panel (no ribbon cable). The most common solutions appear to be; (1) Ignore the problem (my solution); or (2) Install a standard mechanical hour meter (e.g., Honeywell) and connect it to the key switch.

John

[Robin3]

This was a common problem on Volvo tachometer hour meters when we lived in Europe, they don't like damp! The simple cure was to put the tacho in a warm dry place like an airing cupboard/closet for an hour or two to dry out. The hours run record itself was never lost just the display numbers. I had a MD22L Volvo that did this every winter back then,standing it in the airflow from home central heating or from an electric fan (space) heater also worked. Most peeps eventually got annoyed enough to fit a separate inexpensive mechanical number meter. Our current boat here in the USA has a 1998 Yanmar 3GM30F engine but the standard hour meter on that is a mechanical one so no problem.

[Capn Roy]

I agree that dampness is common for causing loss of digits due to dampness. If I do not run the boat heater on a timer in the winter the digits disappear. As soon as the heater is back on the timer the digits reappear.
Local engineer says it is a very common fault in Britain during winter.

[Ostinato]

I'm going to have to tear apart my spare to see if I can get to the lcd display and then look for a ribbon. The tach (with hour meter) is made by VDO.

[2Hulls]

Originally Posted by Robin3

This was a common problem on Volvo tachometer hour meters when we lived in Europe, they don't like damp! The simple cure was to put the tacho in a warm dry place like an airing cupboard/closet for an hour or two to dry out. The hours run record itself was never lost just the display numbers. I had a MD22L Volvo that did this every winter back then,standing it in the airflow from home central heating or from an electric fan (space) heater also worked. Most peeps eventually got annoyed enough to fit a separate inexpensive mechanical number meter. Our current boat here in the USA has a 1998 Yanmar 3GM30F engine but the standard hour meter on that is a mechanical one so no problem.

Thank you for that, Robin. I have two MD22L's and the digital hour reading on both tachs comes and goes willy nilly - mostly gone. Very rarely does one re-appear. Every time one of them reappears I write down the number in my log. I have tried cleaning all the contacts for the entire cable run from the engines with no improvement. This dampness theory gives me another angle to pursue. One time both readings came back simultaneously. This was a real dilemma to process as the two engines and instruments are not connected in any way so they don't know each other exists. How did they both know to come back? I was so enthused I poured a rum and forgot to write down the numbers....

2 Hulls Dave

[Robin3]

Originally Posted by 2Hulls

Thank you for that, Robin. I have two MD22L's and the digital hour reading on both tachs comes and goes willy nilly - mostly gone. Very rarely does one re-appear. Every time one of them reappears I write down the number in my log. I have tried cleaning all the contacts for the entire cable run from the engines with no improvement. This dampness theory gives me another angle to pursue. One time both readings came back simultaneously. This was a real dilemma to process as the two engines and instruments are not connected in any way so they don't know each other exists. How did they both know to come back? I was so enthused I poured a rum and forgot to write down the numbers....

2 Hulls Dave

We had a complete canvas cockpit enclosure but during the season, ie not in winter in the UK, would leave this folded away by default for a quicker getaway after work. when not using the boat in winter we had no problem when the cover was down but if we put left it up and closed off, then the hour mete would stop displaying, so it was OK with cold but not with damp. Pretty dumb piece of design or beta testing IMO to have a display on a boat of all places that fails in 'damp' conditions!, When we sold that boat and bought our next one which came with a Yanmar 4JHE, it had already been fitted with a mechanical counter by the previous owners, probably for the same reason.

A hair dryer blown over the instrument would possibly work and still leave a hand free for a glass of rum!