C-Stack
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Also, If you don't mind, could I see what the battery connection/A-Frame set up looks like on your '76 or your dad's '79??
Here's a better picture of the toilet area. Ignore the mess, I've been focused on the wiring and didn't get into there yet.
Once I get a little better weather and some more courage, I will peel back that duct tape and see what I'm working with. Any tips for re-seating the toilet? I've installed lots of toilets, but never one in a camper.
I'll defer to John on this because both my '76 and '79 are pretty hacked up wiring wise. I haven't gotten into the '76 yet but the '79 had been chopped off and spliced behind the frame header and had a bunch of misc. wires. The '79 now been completely redone and looks slightly different from original.Also, If you don't mind, could I see what the battery connection/A-Frame set up looks like on your '76 or your dad's '79??
Thank for your reply. I believe a previous owner switched out the LP bracket, as the info shows a single bracket.I'll defer to John on this because both my '76 and '79 are pretty hacked up wiring wise. I haven't gotten into the '76 yet but the '79 had been chopped off and spliced behind the frame header and had a bunch of misc. wires. The '79 now been completely redone and looks slightly different from original.
I can get some of the actual frame if that helps but it looks just like yours, except for having a single LP tank bracket instead of the dual tray.
You are correct in that I didn’t remove it. The owner I got her from said the previous owners had removed it. He didn’t know why. They had left the toilet, but he only actually took it out once so he didn’t feel the need to reinstall it. I haven’t really looked at it, to be honest, since I knew I’d need to figure out the power before I’d have a way to pump water to the toilet. This will at least give a starting point.That looks pretty much like I expected. Toilet installation is a little different in an RV vs. a house.
Under the duct tape, you will see more of the same flooring except for a round plastic flange with the hole in the middle. It will look like this:
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The flange is screwed into the plywood floor and the whole thing is threaded into the top of the tank. I see you have a Thetford Aqua Magic IV toilet, which should have a rubber seal on the bottom where it fits into the floor flange. The toilet itself is held in with two uniquely shaped oval bolts that go under the floor flange via two of those open slots and then up through the toilet, then the nuts go on from the top and hold the toilet down.
Before installing the toilet, if you have a way to dump water from the tank, I'd fill it up with buckets of water and make sure it doesn't leak before reinstalling it, since it sounds like you were not the one to remove it.
A lot of models had single tanks standard in the '80s, but it was a factory option to upgrade to dual tanks. Although your tank base plate does look newer.Thank for your reply. I believe a previous owner switched out the LP bracket, as the info shows a single bracket.
Hello! I do understand busy (hence I'm just getting to this a week later), and I very much appreciate you taking your time to help with this. I believe I can do the wiring myself. It seems pretty straightforward and I have tools and some experience.Hi Carla,
Sorry for taking so long to get back to you. I've been busy here lately.
From all your pictures, I have developed this for your battery hookup on the trailer's A-frame area. I will point out a few unanswered questions.
These pictures of yours will show what wires go where. I'm unsure if you can do this work or if you have a relative or friend who can help with the right tools. Or any RV tech can do this. Someone who works in automotive or an electrician has all these tools for repairing wiring and crimping on new terminal connectors for the battery hook-up. You will need a new emergency breakaway switch.
First is the battery positive (+) thick black wire and the thick white battery negative wire (-). Inspect both wires to ensure no burnt-up or open gaps in the wire insulation. Any damaged areas need to be repaired. On the battery black (+) wire, a wire terminal may already exist to bolt to the deep cycle battery. On the battery white (-) wire, that rusty bolt and connection to the chassis ground must be cleaned up. A new 10-AWG wire needs to be acquired and installed from that chassis ground bolt up to the battery with a wire terminal on the end to fit the battery post.
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That will take care of the battery; next is the Emergency Breakaway Switch (EBS) and the blue brake wire. They spliced one leg/wire of the old breakaway switch into the black battery (+) wire. You will need to redo that connection so one of the new wires on the new switch attaches in the same way or similarly. There is no polarity on the EBS, so either wire on the switch is OK.
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Here is where to connect the blue wire to the other wire on the EBS using a waterproof connection.
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That will take care of the battery hookup. There are still some unknowns. Sunline used the wire colors using the RV standard 7-wire plug configuration. Which is a little different from the trailer industry. It looks like this picture is from Etrailer. This gets a little confusing, so I show the pic, but here is where it comes from. Scroll all the way down to find this image. https://www.etrailer.com/faq-wiring.aspx
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Sunline used what is called, a split wire loom tube (the black plastic casing) to hold the individual wires from the 7-wire plug. They for sure used 5 of the 7 potential wires,
Blue = electric brakes
Green = Tail and running lights
Red = Left turn and brake light
Brown = left turn and brake light
White = chassis ground (battery (negative)
We do not know about the black battery charge wire or whether your camper has backup lights, the yellow wire, but some of the older campers did. Knowing what wires they have inside the wire loom tube would be good. Since it is split, you can fold it open, look inside, and see how many wires and colors. See here, as I can see the split in your picture. Have a look and see what is in there.
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You said, so far, you cannot find any junction of the wires coming into the camper where the wire loom goes up into the floor. And that this is, inside the camper where the wires go up into the camper.
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Here is where you can look for a junction of the white chassis ground wire and the blue brake wire. Take a flashlight and look where the flat red cable attaches to. That flat red cable, I "think" is the same flat red cable under the camper popping out where the wire loom goes into the camper heading the brake coils.
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For the EBS to work and the electric brakes, there has to be a junction of some type from the blue incoming wire loom wire from the truck in the 7-wire wire tube to join both the EBS blue wire that goes back out to the EBS and the flat red cable. They cannot create that with only one wire from the truck; it has to split and be joined. It may be under the floor, but you can see the red flat cable; see if you can trace it to the blue incoming wire.
The 7-wire green, brown, and red wires can be one long wire run from the 7-wire plug to this fuse block and never split. They may have even brought the white chassis ground wire there and back to other locations.
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Next is your power converter. I can see the thicker white battery negative and black battery positive wires run to the power converter to feed the circuit fuses. It is still unknown if you have a truck battery charge wire. More on that when you inspect the cables in the wire loom.
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Here is a big unknown you can look into. There is the case of a power converter, but there may not be any 12 VDC power converter control board inside the case. I tried to find anything on that brand of power converter, and it came up empty. They were either bought out or went out of business in the 80s sometime. Maybe a fellow club member, by chance, has some paperwork from their Sunline manual. Being 43 years old, odds are the slime of finding something.
But take a flashlight and look down in the large rectangular opening under the glass fuses to see if any circuit boards are inside. Take a picture if you can. It is not beyond a possibility that the converter/battery charger portion died long ago, and the prior owner unhooked or removed the battery charger portion and just used the battery to run the lights and water pump. They may have charged the battery with a stand-alone charger. See what you can find. We can help if there is no working battery charger/converter, as these do die in time and need to be replaced.
I hope this helps get you started.
Johnb
Hello John,Hi Clara,
This pic is really helpful. It tells us a lot.![]()
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The thicker (heavier gauge wire, most likely 10 awg) white and black fit with the RV industry standard, white is for chassis ground/battery negative, and the black is for battery charging from the truck.
The green is for the clearance, marker, and tail lights.
Brown is for right side (passenger side) turn/stop light (high brightness filament)
Red is for left (driver side) turn/stop light (high brightness filament)
And you have no yellow, which would be backup lights, and you may not have them.
The blue wire is for the electric brakes. It has to be split and joined somewhere as it needs to feed the emergency breakaway switch and the two-wheel brakes. There may be a wire nut junction in the floor where that blue wire enters the camper and then goes back out to the brakes and heads to the emergency breakaway switch. In here, there may be a wire junction of the blue wire. And yes, if that board can be lifted and shine in with a flashlight to see where the wires come up through the floor, it may explain all this.
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Now, the thick black wire has to go to the power converter and the battery positive terminal for the black battery charge wire. Ideally, there is one or two fuses in that black wire.
We do know that the heavy black wire (+ 12 VDC) goes to the battery; we can see it here.
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And in this new picture of yours, I "think" that heavy black wire is in these pics with the tiny white lettering "60C" on the wire insulation under the smaller red wire. Your clear pictures tell a lot. Good job!
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Now, that heavy black also needs to go to the power converter area, and here I know I can see one heavy black wire feeding the power fuse on the power center fuse block. See it here feeding the bottom side of the single glass fuse. That higher amperage fuse protects from a short circuit on the main battery wire and power converter board supply, so as not to overload the system. So this is one of the fuses on that heavy black wire.
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The mystery now is how the black truck battery charger in the seven-wire cable connects to the power converter's main fuse supply and the camper battery on the trailer's A-frame?
If you lift that board and see where the 6 wires in the plastic wire loom come into the camper, it may help shed some light on this. There "might" be a wire nut junction of 3 black wires and maybe a fuse under there.
I hope this helps.
John
Hi Carla,
First off, you are welcome. We are glad to help as we can. And yes, we all know the busy things life throws at us.
Now, back to the camper, lifting that board tells a lot!
This pic of yours, I can now see exactly how they did this.
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The heavy black wires, we can see two thicker black wires coming up from under the camper.
1st blk wire: Is from the 7-wire truck plug known as the battery charge feed to the camper from the truck.
2nd blk wire: Joins in the yellow block, returns through the floor, and heads to the camper battery positive (+) terminal.
Then, out of the same yellow joining block, the 3rd thicker black wire runs to the power converter as the main fused converter charger and battery supply fuse. This all makes sense now.
I'll add this if you want to "upgrade" your system someday. What you have will work on this black battery power feed wire setup; however, as Sunline evolved in building campers, they started adding extra safety features. In this case of the battery power feed wires, they added two more fuses to protect the system.
1. Close to the battery, they added a 30-amp self-resetting circuit breaker in the black wire that connects the battery positive terminal to the camper wiring. This would be in the wire between the battery and that yellow block. This helps protect the wiring from a dead short that somehow happened and started to melt the wire insulation. The wires are exposed out on the A-frame, and if that black wire ever gets smashed to the frame, a dead short happens, and instantly the wire between the battery and the short goes into mega heat and sparking mode. In your case, you do not have this protection, as your only fuse is back at the power converter. The dead short is between the battery and the camper's metal frame, so while that power converter fuse protects against overloading the wire, it does not protect against a direct short along the way to the power converter. To upgrade this, you would add a 30-amp fuse holder or a 30-amp self-resting circuit breaker. The location would be close to the battery's positive terminal. There are a couple of options on how to do that; If this interests you, we can get into it.
2. The truck charge line wire also added a 30-amp fuse in this line. In your case, this can be inside the camper and placed in series with the 7-wire truck plug feed wire to the yellow block. This fuse protects the truck system if a wiring short happens in the camper. There are a couple of options on how to do that; If this interests you, we can get into it.
The above explains the mystery of how they connected the black battery power wires.
I can see in your picture a yellow wire nut under all the wires, and I can see the blue brake power wiring coming up out of the floor from the 7-wire truck plug that goes into that yellow wire nut. That explains how the red two-wire cable under the camper feeds the wheel brakes. While I cannot see the thinner black wire in that red cable, I'm sure it's there. The brake feed red cover cable has a black and red wire in it. This one is under the camper.
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Now to the white wires in that mini bare aluminum bus bar, See here:
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One heavy/thicker white wire is from the 7-wire truck plug. The other heavy, thicker white wire goes back through the floor and up to the battery tray as a chassis ground wire. And the thinner white wire goes to the brakes in that 2-wire red cable. The other heavy white wire is heading to the power converter as the battery negative (-) wire. The thinner white wire may be the ground wire heading to the three glass fuses area for the DOT lights on the camper.
This all adds up now and confirms the wiring on the A frame, as I have told you how to hook it up. I'm out of time now, I wanted to get this much to you. I'll be back later to talk about the power converter.
I hope this helps,
John