Re: [OMC-Boats] Instrument Question

From: jd <jdood@...>
Date: Mon, 2 Mar 2009 14:50:08 -0800

> I have written down in some notes from a few years back that the
> original
> OMC dash oil pressure/water temp gauge was OMC part #172075, and the
> senders were #172127 (oil pressure) and #171960 (water temp).
> However, the key point here is to get senders matched to your Faria
> gauge -
> it's easy to make the gauges plug in mechanically (they're likely
> have NPT
> threads of some sort), but the electrical characteristics must be
> the same.
> The OMC senders will plug into the engine, but many not provide
> appropriate
> readings on your gauges.
> So I'd call Faria, check their website, stop at your local dealer,
> or look
> at the manual for the gauges you found - they should recommend a
> compatible
> sender.
> I would assume you have a "Faria Water/Oil Temperature Gauge" - they
> recommend their temp sender, which comes in 1/8 NPT. The OMC engine
> likely
> has 1/4 NPT, so you'll just need an adapter - you can get it at a
> hardware
> store. I'd probably try to buy a brass one instead of steel or cast
> iron
> so it doesn't rust - if you have trouble finding that, Faria likely
> stocks
> them as well or you could try West Marine, but it'll cost way more
> than a
> hardware store. The specs for the gauge are online here:

wow - this is really helpful. wish i had gotten this email last
summer, after my wild goose chase that still hasn't ended. Yep,
you're right, you supposedly can't just hook up any old sending unit
to any old gauge. But I had no idea you could just put any sending
unit in the engine via an brass thread adapter. Last summer I had
some overheating issue going on (i think). Wanted a gauge that had
actual temp numbers on it, instead of the vaguely glowing red lights
that came with the boat back then. So i tracked down original
sending units, but then had to hook them up to a generic gauge
because of course nobody seemed to having any matching anything out
there for a '65 OMC. So the gauge works, but I have no idea if
the hot reading I get is because the engine is actually overheating,
or if it's because the gauge and senders don't match. It has been
driving my nuts. So knowing I can employ an adapter and make a
Faria set or any other matching set work is great!

So just to clarify, as long as it's a matching set (oil sender/
gauge water sender/gauge) than a person could go with any brand, not
just Faria, right?

> The oil pressure is a bit more complicated - there's different
> combinations
> of senders depending on which gauge you have:
> I'd guess you want the single-station american common ground one,
> but it
> depends on what gauge they're actually selling. Call them at the
> number
> listed in the document and ask.
> All their manuals are online here:
> If you can find out the actual resistance specifications their
> gauges are
> looking for, then you can use much cheaper autmotive parts instead,
> but
> this will likely take some time. Call Faria and ask for the
> resistance
> specs their gauge requires (i.e. "450 ohms at 120 F, 900 ohms at 180
> F"),
> or better yet, ask them for the original manufacturer's part number
> for
> their gauges (they must be hesistant to give you the part number, as
> they
> likely mark the gauges up significantly, but you can usually get it
> out of
> them with some persistence). Then call the manufacturer (which will
> likely
> be in Europe) and ask for a list of US autotmotive applications it's
> used
> in (they'll claim it's confidential information, but usually can be
> talked
> into revealing it).
> Ethan
> --
> Ethan Brodsky
> _______________________________________________
> OMC-Boats mailing list
> OMC-Boats@...
Received on Monday, 2 March 2009

This archive was generated by hypermail 2.2.0 : Tuesday, 29 July 2014 EDT