Another Tachometer Problem

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ps23435
Posts: 39
Joined: Wed Apr 11, 2012 2:32 pm
Location: Suffolk, VA

Another Tachometer Problem

Post by ps23435 »

Hi all. I have just begun experiencing problems with my tachometer. I know there have been several posts regarding problems with tachometers. I've read through them and haven't found similar symptoms to what mine just started doing. Tach has been working well for the 5 years we've owned the boat (there have been a few times it "stuck" but a light tap seemed to correct that). This is different. When the engine is first started the tach reads normally. However, after 10-15 seconds the needle drops to zero. Then it VERY slowly starts to climb at a rate that appears to not be related to engine speed or speed changes. It eventually will drop to zero again with a tap on the dial. I haven't opened up the helm panel yet (or called someone to troubleshoot) but I have checked the alternator connections (they all seem tight, at least as best I can since they are not very inaccessible behind the alternator). Just wondered if anyone has experienced anything similar and if so what they did to correct it. Thanks!
Pete & Anita
Slip Away #437
Hampton, VA
belladonna
Posts: 105
Joined: Fri Mar 22, 2013 12:20 pm
Location: White Stone,VA - lower Ches Bay

Re: Another Tachometer Problem

Post by belladonna »

Yes, I have and now I'm on my 3rd tach, this has got to be the worst piece of equipment that Catalina has ever installed on their otherwise great boats.
Jim Lassiter
2005 Catalina 350 "BELLA DONNA" # 368
White Stone, VA (lower Chesapeake Bay)
KenKrawford
Posts: 614
Joined: Wed Nov 02, 2005 8:54 pm
Location: Atlanta, GA

Re: Another Tachometer Problem

Post by KenKrawford »

Definitely pull out the instrument cluster on the pedestal and check the connections. It's amazing how many electrical problems can be traced to a bad ground or poor connection. Be sure to check the nut holding the connector AND the crimp connector itself. Often times a connector and the crimp will look good but the wire can easily be pulled out.
Ken Krawford
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C350 # 351
Lake Lanier, GA
vineyardsailor
Posts: 14
Joined: Sun Jun 07, 2009 3:07 pm

Re: Another Tachometer Problem

Post by vineyardsailor »

I have has some problems with the tachometer similar to what you are experiencing. I removed the panel, sprayed the trim pot on the back with contact cleaner and moved it back and forth to remove the corrosion. I then returned he pot to its original position (you can tell from the wax seal). About one year later every thing is still working well
nybor
Posts: 248
Joined: Sun Jan 06, 2013 7:55 am

Re: Another Tachometer Problem

Post by nybor »

I agree 100% with Ken et. al. about connections. Before I left for the Dry Tortugas, I turned on my Garmin plotter and....no signal????? frustrated, all I did was unscrew the connector (waterproof) to the GPS antenna, blew across the pins and re-connected it. Bingo.

This also happened to my tach. Intermittent. Unscrew the two wires, look at the two surfaces, prayed to Neptune, reassembled and viola. YOU CANNOT judge a connection simply by an visual, cursory inspection..

dave
jbd3
Posts: 60
Joined: Sat Nov 22, 2008 6:44 pm

Re: Another Tachometer Problem

Post by jbd3 »

Just to add my 2 cents, I had a low voltage under load issue with the 12v accessory plug on the Edson pedestal and a weak/intermittent buzzer when the key was turned on. I ran a supplemental ground to the buss and all those issues disappeared.
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TBOT422
Posts: 424
Joined: Sun Jun 26, 2011 5:36 pm
Location: Clearwater, FL

Re: Another Tachometer Problem

Post by TBOT422 »

Could you be more specific about the 'supplemental bus'? Where did you physically run it? from the battery bank to the ground bus behind the breaker panel? Wire size?

Thanks
Gary & Janet
The Best of Times (Hull #422)
jbd3
Posts: 60
Joined: Sat Nov 22, 2008 6:44 pm

Re: Another Tachometer Problem

Post by jbd3 »

Sure! There is an 8 or 9 inch long plastic connector that connects the feed harness coming up to the pedestal from below with the instrument loom behind the gauge panel. A purple wire entering from below paired up with a black wire that provided ground to the 12v accessory socket, ignition switch, the buzzer circuit and possibly more. After determining that the ground was the reason for low voltage on the accessory plug coupled with trying to clean up all the grounding connections I could get to, I ended up running a 14 gauge wire parallel to the incoming purple that tied off to a large negative feed cable that fed my Raymarine autopilot just aft of the transmission, under the aft berth. Now the buzzer is much stronger, accessory plug works fine, etc. Because of various coatings on the engine harness, it was very difficult to trace the purple wire to the original ground connection, persumably somewhere on engine. Hope that helps
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