Kohler Perkins

[Chuck Wheeler]

Greg,

Sorry for the slow response. We have been on the road for the holidays and I wanted to beat the weather and did not take the time for email etc. We are in California right now. The simple explanation is that any difference in ground between where the gauge is grounded and where the sending unit is grounded causes a current flow that looks to the gauge like a change in the sending unit. When I had a poor ground circuit at the dash I would see a slight change in the gauges when the lights were turned on. Also since the whole circuit is fairly low resistance any problems in the wiring will be reflected in the reading. All my problems, except the fuel gauge sending unit, have been coach wiring. For example the ground connection between the coach and generator was to the generator tray. The connection between the tray and engine block was damaged and was causing my problem.

So far all the gauges in our Wanderlodge seem to follow the Teleflex standard. But they have more than one depending on the series. I have the information at home. I will look around the net the next few days or post it when we return home.

I use an old Resistance Decade box I have when checking my gauges. It lets you dial in the desired resistance. Here is an example of one http://www.mcmelectronics.com/product/TE...0-/72-7270 but I would not buy one. I have also used a 250 ohm and a 100 ohm rheostat to test the gauges by setting the resistance using a multimeter.

- Chuck Wheeler-

1982 FC 31SB Fort Worth TX

---

From: WanderlodgeForum@yahoogroups.com [mailto:WanderlodgeForum@yahoogroups.com] On Behalf Of timvasqz
Sent: Saturday, December 20, 2008 10:39 AM
To: WanderlodgeForum@yahoogroups.com
Subject: [WanderlodgeForum] Re: Kohler Perkins

Chuck, I never understood the gauge ground to be a function of the reading? I understood it to be for the back light? I understand the 'to ignition' was +power to the gauge needel and the -end was a groundstrength to the needel from the sender.as the engine got warmer the grounding in the sender got better (less resistance or more contact)

Is there a standard for a 'resistance value in ohms'per 'reading of temp' or are sender and gauge a matched pair?

Is there a device that you can dial in a resistance value to check the performance of a gauge? I like your test method. our germination equipment require constant review.Review of gauges would be way better than waiting for at-temp peaks to check heater/dial accuracy

This is Greg, I use Tims computer and password. Our style differs. Tim learned to spell at USC and I Rutgers, or was it Rudkers?

GregoryO'Connor of Tim&Greg94ptCa

--- In WanderlodgeForum@yahoogroups.com, "Chuck Wheeler" wrote:
>
> Tim,
> This is a good test of the sending unit and if the wiring is intact, but did
> not show my problem which was corrosion in the dash connector on the common
> return for the gauges. My first indication was when I disconnected the
> temperature gauge and the oil started reading closer to normal. That is
> when I used resistors in place of the sending units to provide a known
> reading. I first place the resistors at the gauges to observe their
> accuracy then at the sending unit locations which tells me what, if
> anything, is being lost in the wiring. The only reason I bring the up is I
> replaced a good gauge because a multimeter does not provide the low
> resistance load of the gauge and wiring or ground problems can be missed.
>
> - Chuck Wheeler-
> 1982 FC 31SB Fort Worth TX
>
>
> _____
>
> From: WanderlodgeForum@yahoogroups.com
> [mailto:WanderlodgeForum@yahoogroups.com] On Behalf Of timvasqz
> Sent: Friday, December 19, 2008 9:03 PM
> To: WanderlodgeForum@yahoogroups.com
> Subject: [WanderlodgeForum] Re: Kohler Perkins
>
>
>
> If you disconnect the sender wire and hook up a multimeter ohms 300
> +to sender -to ground, the meter should show less ohms as the engine
> warms. If you know what the ohms value for 75degree and again for
> 150DegF you could compare it to your test and prove the sender. The
> temp gauge is nothing more than an ohm meter.
>
> I find it best to price the OEM sender and the gauge first. often
> you can find a more modern new pair(sender, gauge) for less than the
> cost to replace one or the other of the classic,OEM hard to find
> parts.
>
> the ohm value for the sender at a given degree has to match the gauge,
> they are a pair. one thing to look at is the scale . you dont need a
> gauge over 250 degrees and under 130 ( the wanderlodge 94,8v92
> watertemp gauge is the worst example of a useful scale)..
>
> Some time the wire between the sender and gauge is screwed. if it is
> close, jump a wire and look to see if a hot engine moves the gauge
> any?
>
> dont use tefflon on a new sender.
>
> an idiot light is prompted by a switch not a sender, they look alike
>
> GregoryO'Connor ofTim&Greg
> 94ptCa
>
> --- In WanderlodgeForum@ orum%40yahoogroups.com>
> yahoogroups.com, "Paul Downey"
> antique405@ wrote:
> >
> > The water temp and oil pressure guages on my 83 PT35 are not reading
> > correctly and i need to replac e the sending units on both. I do not
> > know if these were supplied by perkins,kohler,telflex or BB. I have
> > tried calling BB tech service but get no return call. Has anyone
> > replaced the sending units and if so have any numbers or where to
> > purchase.
> >
> > Paul Downey
> > Versailles Ky
> > 83PT35
> > Our Rollin Home
> >
>