Tach gone whacko

[TwoDuckDad]

My tachometer often indicates an incorrect RPM. It is obviously wrong because it sometimes shows 3K at idle and 2K at WOT. I've read that these tachs were supplied by Faria. Looking for someone who has some experience working with tachs. Is it likely that if it has a signal and showing erroneous RPMs that the tach unit is likely bad or perhaps another part of the system? Will this one work? https://fariabeede.com/2-pages/aftermarket.php

[Titaniumboy]

Faria might be able to repair your existing tachometer.

[TwoDuckDad]

After further reading it appears my next step should be to check all the connections on the rear of the unit and be sure the cylinder switch is on "8". I assume like most tachometers, there is a magnetic pickup somewhere on the engine. Does this go bad or is my problem likely with the tach (including connections)?

[billk2632]

Yes, check the connections - there is a switch on the back of the tach that selects how many cylinders, turn that switch (usually use a screwdriver) through all the settings once or twice - the connections tend to corrode and make the tach go wacky.

[kas232ca]

Mine occasionally reads about 1500 too high. I just tap it and it then works for the rest of the day correctly.

[Cruiser64]

Mine occasionally reads about 1500 too high. I just tap it and it then works for the rest of the day correctly.

My 07 220 did the exact same thing. Give it quick tap in the center of the glass and you were good to go.

[TwoDuckDad]

spoke to a tech support guy at Faria and he confirmed: first move the cylinder knob back and forth and then be sure it is on the correct spot per the legend printed next to the knob. Take the boat out and confirm if that worked. If not, remove and clean all connectors and be sure wiring is in good condition. If I'm getting a signal but the wrong indication of RPMs then it is likely the unit. Cost to replace is about the same as repair so a new one is the better choice. Planning to do that during the next nice weather day. Since I had to wait a few days for good weather and I'm gonna be "under the hood", I decided to upgrade the speedo to the Faria GPS unit which is more accurate and much easier to read any speed under 30 mph since the new speedo begins at 0 (versus 10) and the graduations between each 10 MPH is the same. I'd attach photos but it appears this forum doesn't allow me to simply insert from my laptop. Anyone know a work around besides having an online photo storage? (which I'm not a fan)

[Daniel]

I had my 2003 tach repaired by Faria and it works perfectly now. Verified accurate by vessel view.

[jhnmdahl]

spoke to a tech support guy at Faria and he confirmed: first move the cylinder knob back and forth and then be sure it is on the correct spot per the legend printed next to the knob. Take the boat out and confirm if that worked. If not, remove and clean all connectors and be sure wiring is in good condition. If I'm getting a signal but the wrong indication of RPMs then it is likely the unit. Cost to replace is about the same as repair so a new one is the better choice. Planning to do that during the next nice weather day. Since I had to wait a few days for good weather and I'm gonna be "under the hood", I decided to upgrade the speedo to the Faria GPS unit which is more accurate and much easier to read any speed under 30 mph since the new speedo begins at 0 (versus 10) and the graduations between each 10 MPH is the same. I'd attach photos but it appears this forum doesn't allow me to simply insert from my laptop. Anyone know a work around besides having an online photo storage? (which I'm not a fan)

I've heard reports that moving the number of cylinders knob on the back, side to side several times, can effectively clean the contacts and make an inconsistent tach work well again. Might as well try it before sending it in or replacing it.

As for photos, if you click the "Full Editor and Preview" button when composing a response in the Quick Reply window, it will open a bigger reply page where you can clock on "attachments" down below the text box and directly upload and attach a photo to your post, including placing it inline with your message.

John

[TwoDuckDad]

thanks John. This is the speedo I'm getting.

[TwoDuckDad]

Note to self: Always check to make sure I'm logged into this forum prior to typing a reply. Otherwise once you log in your text disappears! The maneuvering of the cylinder indicator knob on the back of the tach did the trick. I also installed the new Faria GPS speedo. Sea trial completed this morning under blue and sunny skies above Lake Lanier. I learned several things during the projects. First, it really helps to have a 3/8 deep well socket to remove and install the brass nuts on the speedo. Second, one must plug the black hose that went to the old speedo that is not used on a GPS speedo or it will leak. Third, having the right tools, connectors, etc. makes the job go better and more enjoyable. Fourth, calling Faria tech support prior was money. The guy gave me very good advice, it was perfectly accurate, and he was an American who spoke perfect English. Fifth, always search the forum and seek advice prior to beginning a project to see what you can learn from others. Thanks to all who contributed in the past and now.

[AsLan7]

Great words of wisdom TDD.

[bruceb58]

Second, one must plug the black hose that went to the old speedo that is not used on a GPS speedo or it will leak.

Better yet, completely remove it.

[Titaniumboy]

Any pictures of the instrument cluster after the speedometer install? I’m curious how well the new speedometer matches the original gauges.

How much would this cost me if I wanted to upgrade the twin of your boat?

[Big Block Power]

Second, one must plug the black hose that went to the old speedo that is not used on a GPS speedo or it will leak.

Better yet, completely remove it.

It's a new option! A cockpit shower!