black tank question

[kstockwell]

Matt,

So, I swapped the LP and the Holding tank

normal
LP in LP - full
HT in HT- below E

swapped
LP in HT- above F
HT in LP- normal Empty (when it should be F)

its like something is backwards?
--
1978 Kingsley
Putney VT

 

[Matt Colie]

> Matt,
>
> So, I swapped the LP and the Holding tank
>
> normal
> LP in LP - full
> HT in HT- below E
>
> swapped
> LP in HT- above F
> HT in LP- normal Empty (when it should be F)
>
> its like something is backwards?

OK Kelly,

That experiment has proved that the black tank gauge is bad and the black tank sender is good.

Now you need to start canvasing the parts coach owners for a good gauge.

Yes, the calibration of everything sucks, but all are that way always......

Matt
--
Matt & Mary Colie - '73 Glacier 23 - Members GMCMI, GMCGL, GMCES
Electronically Controlled Quiet Engine Cooling Fan
OE Rear Drum Brakes with Applied Control Arms
SE Michigan - Twixt A2 and Detroit

 

[kstockwell]

Thank you Matt
but, the LP gauge in the HT read above H... It should have read E?

Or, are they looking for different things?

I assumed all along that the fresh water and the holding tank operated the same so those are the ones I had been switching.

Are they different?

And, Anyone out there have an old Holding Tank gauge?!
--
1978 Kingsley
Putney VT

 

[Jim Hupy]

Again, so many variables. Is the coach level fore and aft? Port to
starboard? This will have a huge influence on accuracy of your gauges. They
are at best an approximate reading. If you are really curious, take your
CSI flashlight, turn the pump off, step on the flush valve and shine some
light down the toilet. That will settle the question for sure.
Also, make sure that no waste or toilet paper is hung up on the
senders. It varies the resistance of the circuit enough to change the
readings on the gauge.
In most coaches, the portable water tank equals the volume of the waste
tanks, so when your pump starts to run, you need to empty your tanks. Of
course, if you are hooked up to city water, that does not apply. Large,
shallow, flat tanks don't help things either.
Jim Hupy

> Thank you Matt
> but, the LP gauge in the HT read above H... It should have read E?
>
> Or, are they looking for different things?
>
> I assumed all along that the fresh water and the holding tank operated the
> same so those are the ones I had been switching.
>
> Are they different?
>
> And, Anyone out there have an old Holding Tank gauge?!
> --
> 1978 Kingsley
> Putney VT
>
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
>

 

[kstockwell]

It's not that the gauge is inaccurate, it's that it's giving dummy readings. Going WAY below E when clicked on/ or when the gauge is moved to the LP
head it goes WAY above F. I have a flashlight, a stick with 1/2" increments sharpied on it and use that to check my black tank level. But it seems
like the gauge readings aren't right; let alone not accurate. So I want to troubleshoot what I can w/out getting too gross about it

> Again, so many variables. Is the coach level fore and aft? Port to
> starboard? This will have a huge influence on accuracy of your gauges. They
> are at best an approximate reading. If you are really curious, take your
> CSI flashlight, turn the pump off, step on the flush valve and shine some
> light down the toilet. That will settle the question for sure.
> Also, make sure that no waste or toilet paper is hung up on the
> senders. It varies the resistance of the circuit enough to change the
> readings on the gauge.
> In most coaches, the portable water tank equals the volume of the waste
> tanks, so when your pump starts to run, you need to empty your tanks. Of
> course, if you are hooked up to city water, that does not apply. Large,
> shallow, flat tanks don't help things either.
> Jim Hupy
>

>
> > Thank you Matt
> > but, the LP gauge in the HT read above H... It should have read E?
> >
> > Or, are they looking for different things?
> >
> > I assumed all along that the fresh water and the holding tank operated the
> > same so those are the ones I had been switching.
> >
> > Are they different?
> >
> > And, Anyone out there have an old Holding Tank gauge?!
> > --
> > 1978 Kingsley
> > Putney VT
> >
> > _______________________________________________
> > GMCnet mailing list
> > Unsubscribe or Change List Options:
> > http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
> >
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org

--
1978 Kingsley
Putney VT

 

[Matt Colie]

> I don't think the gauge is inaccurate (though it could be that too), I think it's that it's giving dummy readings. Going WAY below E when clicked
> on/ or when the gauge is moved to the LP head it goes WAY above F. I have a flashlight, a stick with 1/2" increments sharpied on it and use that to
> check my black tank level. But it seems like the gauge readings aren't right; let alone not accurate. So I want to troubleshoot what I can w/out
> getting too gross about it

Kelly,

That was a very good experiment.

If the same gauge gives you a below E in one place and an above F in an other, that gauge is unquestionably bad.
Particularly as the good one reports reasonably realist values.
So, you know one is probably bad and one is probably usable. Put the word out that you want one more. If you have a friend that does electronic
things, take show him the bad one and ask him to look at the solder joints. I have had old stuff lose a spot or two in the years. Maybe it can be
saved.

Matt

--
Matt & Mary Colie - '73 Glacier 23 - Members GMCMI, GMCGL, GMCES
Electronically Controlled Quiet Engine Cooling Fan
OE Rear Drum Brakes with Applied Control Arms
SE Michigan - Twixt A2 and Detroit

 

[kstockwell]

It did read correctly in the fresh water tank spot. Normal old E reading. The fresh water unit reads WAY below E in the holding tank spot (same as
the Holding Tank). The fresh water unit reads correctly, gets to F and overfills.

--
1978 Kingsley
Putney VT

 

[Matt Colie]

> Holding Tank did read correctly in the Fresh Water tank spot. Normal old E reading. The fresh water unit reads WAY below E in the holding tank
> spot (same as the Holding Tank). The fresh water unit reads correctly, gets to F and overfills.
>
> FT fresh tank
> HT holding tank
> LP propane
>
> So
> HT plugged into HT way below E, bad should be E
> HT plugged into LP way above F, bad should be F
> HT plugged into FT normal reading, on E
>
> FT plugged into FT normal reading, on E
> FT plugged into HT way below E, bad should be E
>
> LP plugged into LP, normal reading, F
> LP plugged into HT, way above F, bad should be E
>
> Just trying to be thorough, and determine if the unit is bad or not.

Kelly,

Not all of this makes sense, but nobody said you can only have one problem at a time.....

Matt
--
Matt & Mary Colie - '73 Glacier 23 - Members GMCMI, GMCGL, GMCES
Electronically Controlled Quiet Engine Cooling Fan
OE Rear Drum Brakes with Applied Control Arms
SE Michigan - Twixt A2 and Detroit

 

[kstockwell]

I think you're right; I have more than one issue...

You mentioned the wired leading to the unit, I have 5. from top to bottom
white
yellow
space
black red
space
space
purple

the purple looks stressed and possibly charred.
Where can I find a diagram as to what those wires should be carrying?

I get the +12, ground is for my battery and to power the unit/gauges. What should the others be? Am I missing any wires? Looking into the casing it
doesn't look like there's a broken off wire.

> > Holding Tank did read correctly in the Fresh Water tank spot. Normal old E reading. The fresh water unit reads WAY below E in the holding
> > tank spot (same as the Holding Tank). The fresh water unit reads correctly, gets to F and overfills.
> >
> > FT fresh tank
> > HT holding tank
> > LP propane
> >
> > So
> > HT plugged into HT way below E, bad should be E
> > HT plugged into LP way above F, bad should be F
> > HT plugged into FT normal reading, on E
> >
> > FT plugged into FT normal reading, on E
> > FT plugged into HT way below E, bad should be E
> >
> > LP plugged into LP, normal reading, F
> > LP plugged into HT, way above F, bad should be E
> >
> > Just trying to be thorough, and determine if the unit is bad or not.
>
> Kelly,
>
> Not all of this makes sense, but nobody said you can only have one problem at a time.....
>
> Matt

--
1978 Kingsley
Putney VT