House power

OK finally we figured out what coach and electrical system he has:
It is a 1976 Palm Beach with a 50 amp 240 volt shore power
connection.

Now you need to figure out if he is
1. moving the shore power cord correctky between the shore power and the Onan receptical.
2. If everything works correctly on shore power then everything from the shore power connector on into the coach is OK. This is because all of the
same stuff is used by both shore and Onan power.
3. The problem has to be between the Onan 4 prong 50 amp receiptical, back to the Onan itself.

I would first be checking the Onan voltage at one of the house plugs for 120 VAC and around 60 cycle. If that is good I would be checking for 120VAC
at the output of the circuit breaker for the converter. If that is missing, then the only other place to look is on the back of the 50 amp Onan
connector for the jumper that connects the hot leads together or to one of the female connectors. You might just have a dirty or burned female
connector terminal.
--
Ken Burton - N9KB
76 Palm Beach
Hebron, Indiana
 
What Ken B said. Quick and dirty - take your AC voltmeter set for 110V. Fire up the genset but don't connect the coach cable. Measure voltage
between each of the two side blade connectors and the top blade - not the u-shaped socket which is safety ground. You should get 110V each way. If
you don't, make everything cold and pull the socket out and look at the back of it. There's likely one of the connections which are jumpered loose.

--johnny
--
Foolish Carriage, 76 26' Eleganza(?) with beaucoup mods and add - ons.
Braselton, Ga.
I forgive them all, save those who hurt the dogs. They must answer to me in hell
 
> 1976 Palm Beach

Samuel,

Welcome to the group, family, cult, asylum.....

Well, I guess that I don't have to tell you that there are many here with a lot of experience with GMC electrics (not to mention that a few were EEs
before they even got to being owners).

You have also already had a good introduction to why we encourage the new people here to write sigfiles. You can do this easily as you are working
the group from the forum. Go to then find and scroll down a little and you will see the Signature
box. Fill in the name you want to be known by (so we know who we are helping), a short about the coach including major mods (it can matter a lot -
did you notice that the answers got more specific when we found out that you had a 76PB?) and lastly a geographic reference as those that work the
list by e-mail can't see the Pittsfield, IL in the header. This will allow us to be much more effective with you questions. There may also be
someone in striking distance that can assist you.

But, as soon as you are though there, if you do not have all the service documentation for everything, go to GMCMI and download everything you don't
have. Three of those should be the wiring diagrams for Chassis, House 12V and 120V. If you print them carefully, you can tape them up as a mosaic
and they will be very helpful. You are obviously literate and have a IQ over 80, so you are ahead of many of those that you might be trying to pay to
do what the coach needs. Yes, it will need a lot of attention. It is a 40+ year old vehicle (not a truck) carrying a same age house that has been
though a continues earthquake. With care, they can be reliable. If you don't have a good grease gun, get one and a couple of tubes of Valvoline
Synpower. That grease is pricey, but grease is way less expensive than parts....

In the case that you may not have noticed, the real value in being the owner of a TZE is not that you have a new big toy, but it is the community that
it connects you to. There are several thousand brand old friends that are available for some level of assistance. You may have already started, but
trust me, you have not yet seen this community work the magic it is capable of. The power that can be brought to bear here is truly awesome.

There is an International Convention coming up in early October (~03~10) in Mansfield OH. That is about 550 miles from Pittsfield, that is a very
long day or two short road days. If you can get the time and can make it there, it is worth your while to do so. If you don't and with a new coach
and still employed, we will understand. But you should watch for the next fall rally. Speaking of which, you are in Great Lakers country. We
(GMCGL) have rallies all the time and all over. Get to our website and watch for one that you can make. The next is in Algonac MI and that too would
be kind of a long run for a new owner. (This will almost be a joke for you before long, we don't even count excursions that we can make in a single
day.)

Now, as I said before this is a community of helping and supportive people the likes of which you may never have known. The only one like it that I
know of is that of the watermen that are my world. For this reason, I took up welcoming new owners here much as one would be welcomed there. So,

May the Good Lord bless this coach and all those that set forth within her.

Welcome Samuel

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
 
> Everything "does" work on shore power - lights, roof vent fans, ac, refrig, and receptacles. ONAN - only thing working ac & receptacles. No
> lights, refrig, or vent fans.

Samuel,
(I am not one of the EEs, but I worked on ships as an electrician.)

You have got a very interesting problem here.
Everything works when on shore power.
The DC parts quit when on the Onan?
The lights, reefer and fans are all DC....
But the house bank must be good to start the Onan.....

Is the reefer a 2-way LP and AC? If it is AC and DC only, leave it off until you are sure that the Onan is running at frequency.

Here is a stretch -
There is a bad connection between the house bank and the DC panel.
You still have a Buzz-box for a converter and the Onan is enough off so it is not working so no DC output.
Unplug the converter and find out what stopped. If that is the DC list, chase the connection from the house bank to the DC panel.

While you are at it, go get a device called a "Kill-A-Watt". This will measure voltage and frequency. If the frequency is far off, adjust the
governor.

Yes, the Onan receptacle is the one that the shore plug should be in inside the shore power storage box.

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
 
If everything is working on shore power then the cord going into your breaker box and the breakers must all be OK. So the problem has to be either in the cord coming from the Onan or in the 50 amp receptacle that is mounted in the electrical compartment. Since the Onan puts our 120 volts there is a jumper inside the receptacle that feeds that 120 volts to both sides of the breaker box. Since you are missing power to half of your circuits I would think that you have a loose connection in the receptacle. Take the receptacle out of its box and check the screws and wire connections on the back side and you should find your problem.

Be sure not to have the Onan running when you do this.

Emery Stora
77 Kingsley
Frederick CO

>

>> 1976 Palm Beach
>
> Samuel,
>
> Welcome to the group, family, cult, asylum.....
>
> Well, I guess that I don't have to tell you that there are many here with a lot of experience with GMC electrics (not to mention that a few were EEs
> before they even got to being owners).
>
> You have also already had a good introduction to why we encourage the new people here to write sigfiles. You can do this easily as you are working
> the group from the forum. Go to then find and scroll down a little and you will see the Signature
> box. Fill in the name you want to be known by (so we know who we are helping), a short about the coach including major mods (it can matter a lot -
> did you notice that the answers got more specific when we found out that you had a 76PB?) and lastly a geographic reference as those that work the
> list by e-mail can't see the Pittsfield, IL in the header. This will allow us to be much more effective with you questions. There may also be
> someone in striking distance that can assist you.
>
> But, as soon as you are though there, if you do not have all the service documentation for everything, go to GMCMI and download everything you don't
> have. Three of those should be the wiring diagrams for Chassis, House 12V and 120V. If you print them carefully, you can tape them up as a mosaic
> and they will be very helpful. You are obviously literate and have a IQ over 80, so you are ahead of many of those that you might be trying to pay to
> do what the coach needs. Yes, it will need a lot of attention. It is a 40+ year old vehicle (not a truck) carrying a same age house that has been
> though a continues earthquake. With care, they can be reliable. If you don't have a good grease gun, get one and a couple of tubes of Valvoline
> Synpower. That grease is pricey, but grease is way less expensive than parts....
>
> In the case that you may not have noticed, the real value in being the owner of a TZE is not that you have a new big toy, but it is the community that
> it connects you to. There are several thousand brand old friends that are available for some level of assistance. You may have already started, but
> trust me, you have not yet seen this community work the magic it is capable of. The power that can be brought to bear here is truly awesome.
>
> There is an International Convention coming up in early October (~03~10) in Mansfield OH. That is about 550 miles from Pittsfield, that is a very
> long day or two short road days. If you can get the time and can make it there, it is worth your while to do so. If you don't and with a new coach
> and still employed, we will understand. But you should watch for the next fall rally. Speaking of which, you are in Great Lakers country. We
> (GMCGL) have rallies all the time and all over. Get to our website and watch for one that you can make. The next is in Algonac MI and that too would
> be kind of a long run for a new owner. (This will almost be a joke for you before long, we don't even count excursions that we can make in a single
> day.)
>
> Now, as I said before this is a community of helping and supportive people the likes of which you may never have known. The only one like it that I
> know of is that of the watermen that are my world. For this reason, I took up welcoming new owners here much as one would be welcomed there. So,
>
> May the Good Lord bless this coach and all those that set forth within her.
>
> Welcome Samuel
>
> 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
>
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
 
Matt, that is an interesting call that the Onan speed could have been monkeyed with and since the output is directly related to the speed of the
generator it could be effecting the operation of the OEM or maybe even a replacement converter. Could he plug an extension cord in a 110 receptical
and put thru a window to the gen area and use a VOM to roughly set voltage to 120 volts as he adjusts generator speed?

> > Everything "does" work on shore power - lights, roof vent fans, ac, refrig, and receptacles. ONAN - only thing working ac & receptacles. No
> > lights, refrig, or vent fans.
>
> Samuel,
> (I am not one of the EEs, but I worked on ships as an electrician.)
>
> You have got a very interesting problem here.
> Everything works when on shore power.
> The DC parts quit when on the Onan?
> The lights, reefer and fans are all DC....
> But the house bank must be good to start the Onan.....
>
> Is the reefer a 2-way LP and AC? If it is AC and DC only, leave it off until you are sure that the Onan is running at frequency.
>
> Here is a stretch -
> There is a bad connection between the house bank and the DC panel.
> You still have a Buzz-box for a converter and the Onan is enough off so it is not working so no DC output.
> Unplug the converter and find out what stopped. If that is the DC list, chase the connection from the house bank to the DC panel.
>
> While you are at it, go get a device called a "Kill-A-Watt". This will measure voltage and frequency. If the frequency is far off, adjust the
> governor.
>
> Yes, the Onan receptacle is the one that the shore plug should be in inside the shore power storage box.
>
> Matt

--
C. Boyd
76 Crestmont
East Tennessee
 
More 'n likely that little Tommy Tinkerer has had his hands in where they
had no business being. Sounds to me like they have split off 12 volt
lighting from the house batteries and switched it to the engine battery,
and the engine battery is perhaps discharged.
In any event, some serious investigation work is in order, sooner than
later. Keep engine functions separate from house functions. And really,
really, keep everything insulated from ground points except where they are
supposed to be. The factory wiring schematics are your best friend here.
You know that bulky folded up bunch of paper in the back of your manual,
that's the one.
Jim Hupy
Salem, Oregon

On Tue, Sep 10, 2019, 7:39 AM Matt Colie via Gmclist <

> > Everything "does" work on shore power - lights, roof vent fans, ac,
> refrig, and receptacles. ONAN - only thing working ac & receptacles. No
> > lights, refrig, or vent fans.
>
> Samuel,
> (I am not one of the EEs, but I worked on ships as an electrician.)
>
> You have got a very interesting problem here.
> Everything works when on shore power.
> The DC parts quit when on the Onan?
> The lights, reefer and fans are all DC....
> But the house bank must be good to start the Onan.....
>
> Is the reefer a 2-way LP and AC? If it is AC and DC only, leave it off
> until you are sure that the Onan is running at frequency.
>
> Here is a stretch -
> There is a bad connection between the house bank and the DC panel.
> You still have a Buzz-box for a converter and the Onan is enough off so it
> is not working so no DC output.
> Unplug the converter and find out what stopped. If that is the DC list,
> chase the connection from the house bank to the DC panel.
>
> While you are at it, go get a device called a "Kill-A-Watt". This will
> measure voltage and frequency. If the frequency is far off, adjust the
> governor.
>
> Yes, the Onan receptacle is the one that the shore plug should be in
> inside the shore power storage box.
>
> 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
>
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
>
 
> Johnny,
> Are you referring to the 50 amp receptacle in the cord box?
>
> Sam

Yes he is.
--
Ken Burton - N9KB
76 Palm Beach
Hebron, Indiana
 
Sam, be careful when measuring AC. If your meter probes don't reach the contacts in the Onan socket, you'll have to take the socket loose and turn it
around. Make everything cold before you do this. if you find both 110 sockets are connected via a jumper, not loose, and clean, you've moved beyond
what I can think of at a distance, and need to graze The Black List for an experienced owner close to you to help. From what you've posted, your PO
has played with the wiring, and some of it shook loose someplace. Put it back to factory, prove each wire with your ohmmeter, and it ought to work
correctly.

--johnny
--
Foolish Carriage, 76 26' Eleganza(?) with beaucoup mods and add - ons.
Braselton, Ga.
I forgive them all, save those who hurt the dogs. They must answer to me in hell
 
> Sam, be careful when measuring AC. If your meter probes don't reach the contacts in the Onan socket, you'll have to take the socket loose and
> turn it around. Make everything cold before you do this. if you find both 110 sockets are connected via a jumper, not loose, and clean, you've
> moved beyond what I can think of at a distance, and need to graze The Black List for an experienced owner close to you to help. From what you've
> posted, your PO has played with the wiring, and some of it shook loose someplace. Put it back to factory, prove each wire with your ohmmeter, and
> it ought to work correctly.
>
>
> --johnny

I was going to offer to come help him or have him come this way until I realized that it is 280 miles one way. There ought to be someone closer.
--
Ken Burton - N9KB
76 Palm Beach
Hebron, Indiana
 
Yeah. Description points at miswiring and something loose. It will be time consuming to find, but that's all it will be. And even though it worked
before whatever came loose or opened or whatever, it need to be set back to stock.
Sam, if there's nobody closer, hot up both batteries and strike out for Chuck's place one morning.

--johnny
--
Foolish Carriage, 76 26' Eleganza(?) with beaucoup mods and add - ons.
Braselton, Ga.
I forgive them all, save those who hurt the dogs. They must answer to me in hell
 
Just a thought, but my beloved PO installed a newer Onan Emerald Plus 6500 watt generator, and wired it up so that its output went not to the breaker
box, but to a female 50 amp socket in the generator compartment. That way, the house power can be transferred between the shore power and generator
by just moving the shore power plug. Simple, elegant, cheap and very effective. And that kept the autoswitch for my inverter down to a 2-way switch
(a whole lot simpler than a 3-way).
--
Mark Hickey
Mesa, AZ
1978 Royale Center Kitchen
 
In past posts, I assumed I had issues with an alternator after having to change out on alternator 3 times already, I have traced battery wires from
the front of the coach (engine battery) to the house battery. I have ordered solenoid to replace the solenoid on passenger side engine compartment. I
have ordered an isolator box from NAPA last Friday and it is over a week getting here, to which UPS claims the item possibly got lost or misplaced.
(Imagine that!!)
I am at a loss with the large cable with red coating on it, coming from the left side of the solenoid located on the passenger firewall, next to the
isolator box. The wire is strapped to the frame behind the grill and runs to the driver's side section and then goes into the body of the camper.
(From here, I have no clue) I thought I had found the other end of this cable at the block behind the Converter/Breaker box across from bathroom.

I did remove the Converter box and Breaker Box today and found a "block" that a battery cable wire connects to. With the house battery connected, this
wire has 11.5 -12 volts. I did unhook the wire which appears to be going back to the front of the camper, and while hooked to a battery, it is showing
12 volts. The wire on the block is "zero" I am unsure if the cable I am mentioning is in fact the booster cable...

I do have several decent pictures of the areas I am trying to explain. I must admit when I look at a schematic or any other electrical drawing, it
comes across to me a trying to read Chinese, which I have no clue of. I am more of a type of person, if I can get my hands on it and be able to look
at how it is to go, I can eventually figure it out.

I do apologize for my ignorance and to assure all, I jumped in this purchase of this RV to learn the aspects of how to keep it maintained and serviced
when needed. If and When I get the bugs worked out, it will be going on the road!!! Please forgive me for my ignorance with the above mention, but I
am convinced I will not let this eat my lunch or kick my butt.

I do have a few photos I have taken, but it seems when I try to upload them, I am advised they are too big to send. Another task I am sure I will
eventually figure out.

1976 Palm Beach
Samuel Ferguson
Tele 217-491-2969
--
Samuel Ferguson
Pittsfield, Illinois
(West Central Illinois)
1976 GMC Palm Beach (A newbie who will not allow this thing to kick my butt!!)
 
Samuel,

You said: "I must admit when I look at a schematic or any other electrical drawing, it comes across to me a trying to read Chinese, which I have no
clue of. I am more of a type of person, if I can get my hands on it and be able to look at how it is to go, I can eventually figure it out."

You have friends here! There are many who struggle as you do, but I'll wager that in time you'll be expert in the systems of the coach. You seem to
have the stick-to-itiveness that it takes to understand 1970's engineering. The nice thing about that era is that the engineering can be culled by
observation, mostly, whereas today it's burned on a chip or written in code.

We have a lot of Palm Beaches around and you are near enough to many who like to gather that once you get amongst 'em you'll absorb things quickly.
Also, we GMC'ers love to talk about our coaches.

I can't wait to hear reports of successful journeys around the midwest.

Good luck,
--
Larry Davick
A Mystery Machine
1976(ish) Palm Beach
Fremont, Ca
Howell EFI + EBL + Electronic Dizzy
 
Sam, no one need apologize for ignorance, it can be fixed with information, and you're getting a fair amount :) (Those who refuse information have
progressed to stupidity which isn't really fixable). Let's recap since there has been a lot of information and a bit of speculation so far. It
appears that all of your AC powered equipnment works whether you are using the genset or have the coach plugged to shore power. This pretty much
proves the AC part of things, with the possible exception of one side of the socket which provides genset power to the plug in cord. Correct?
Now, it appears that there is no DC power to the lights, fans, etc., which all run off DC. There is a 12 volt converter (several names we use, but GM
calls it the converter) which is supposed to provide DC power when the coach has AC power privided and charges the house battery in the bargain. When
there is no AC power, the lights, fans, etc. run off the house batteries. As I understand it, you don't have the 12 volt equipment working whether
the AC is on or not. Correct? As I further understand it, the wiring in the coach 12 volt system is suspected to have been moved about by a PO.
Correct?

We can go from there.

--johnny
--
Foolish Carriage, 76 26' Eleganza(?) with beaucoup mods and add - ons.
Braselton, Ga.
I forgive them all, save those who hurt the dogs. They must answer to me in hell
 
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