Instrument light wiring

[Mike and Joanne Stimmler]

Could someone tell me which switch the instrument lights (tach,volts,temp,oil pressure)normally connect too. Mine have never worked and this past weekend I found out why when I had the panel off for the first time to replace the tach/hour meter. They weren't connected to anything and all but two of the bulb sockets were missing.I'm thinking that the running lights circuit would be a logical place, but what is the norm?

Mike

[Craig Illman]

Mike - I think mine are wired to the ignition, so they're on when the key is on.

Craig

[Ken Juul]

Concur with Craig. 

A good reason to burn the engine instrument lights all the time is to keep the gauges from fogging up.  But that is kind of like the chicken and the egg.  Do the cooling lights/instruments cause moisture to be drawn in necessitating burn off the next time? Or does fogging up occur anyway? Since yours have been disconnected, after you get them working please give us some feedback.

[steve stoneback]

Mike,
I hope that tach/hour meter work for you......  I don't know why it wouldn't, it worked fine when I changed out my panel.  I still have the rest of my old panel.  Do you need some light sockets.  The price is right, you pay the postage and they are yours.
Steve

[Stu Jackson]

The engine wiring harness article has a good diagram for cockpit engine panel wiring to the instruments, and is here: http://www.c34.org/wiki/index.php?title=Engine_Harness_Upgrade

Mike, most all I've seen have been ON all the time once the ignition key is turned on.  As Ken mentioned, one of the way-old tech notes mentioned the value of having them on all the time to prevent fogging.  Since then, Teleflex has come out with new anti-fogging dials, but I've seen no need to replace them with these more expensive models.  I did replace the voltmeter pretty soon after we got the boat in '98.  For other instruments you may have, you may want to consider having them turn on only when the running lights come on.  My compass light, for instance, only comes on when the running lights are switched on.

"Behind the panel" whether in the cockpit or the main panel, is something you should become somewhat familiar with - fun stuff back there!

[Mike and Joanne Stimmler]

Steve,
Yes, your tach/hourmeter worked just fine, however at first I didn't think it was. In trying to test it at home, I thought I could simply connect 12 volts to the hour meter part of the gauge and verify that it would count the hours and it didn't. Then I took it to a local automotive shop and it tested just fine. Apparently you must also have a signal from the Tach input (alternator)for the hour meter to work. I was able to confirm that the light also works on the Tach so all will be fine once I get the lights connected to a 12 volt source. It should be a simple mater to run a short jumper from the switch to the lights.
I may consider buying the rest of the instruments from you if their still available.

Mike

[Tom Soko]

Mike,
I've read the suggestions about keeping the instrument lights on whenever the engine (ignition switch) is on.  I resepectfully disagree.  About 12 years ago I rewired my engine panel (at the same time I put in the wiring harness upgrade), and decided to tie the engine panel lights into the running lights breaker.  I'm very happy that I did.  I used to see fog inside the instruments often, which would "burn off" after running the engine for an hour or two.  Since I made the change, the instruments hardly fog up at all. 

[Ken Juul]

Thanks for the input Tom.
Drats, another wiring change to deal with.

[Craig Illman]

Tom - Ok, so wouldn't the ideal thing be a relay that the ingition energizes? So you're not burning amps lighting the gauges whilst sailing at night and not being real concerned about the water temperature of the engine? 

Craig

p.s. yet another opinion from us wanna-be enigineers without the real talent to do it professionally....

[Mike and Joanne Stimmler]

Or maybe just wire in a toggle switch on the panel off the ignition switch to the lights.

[steve stoneback]

Mike,

Yes, it is available.  I am curious, were you able to figure out how to set the hour meter to match the hours of your failed tach instead of the hours that were on my engine?

Steve

[Mike and Joanne Stimmler]

Steve, no I wasn't. I'll just have to add the appropriate hours on paper. At least I'll be able to keep track of my fuel usage. Your dip switch settings were all the same as mine.

Mike

[Ron Hill]

Guys, Susan & D.G. : A couple of years ago I wrote a Mainsheet article about changing out the auto type 194 instrument bulbs to Red LED lights.  I point out that the 194 bulbs put out tooo much heat !! and will burn the bulb holder.
I have mine wired to the ignition switch and have no problem.
Great information in those Mainsheet tech notes, but only if they are read !!  A thought

[Mike and Joanne Stimmler]

Ron,
That sounds like a good idea with the red LED lights. I'm sure there allot cooler but are they bright enough to see the gauges clearly?

Also, do you have a part number and a source where their you can buy them, or are they a common item?

Mike

[Ron Hill]

Mike : What you ask, is all written up in that Mainsheet article !!