My 1978 GMC motorhome
- Thread starter Mike_H
- Start date
OP
OP
I talked to her yesterday about that. She's not interested, yet...We'll see if I can convince her. I actually enjoy the process tho.
OP
So after pissing around with my battery drawer for far too long, trying to get it to fit in the space I intended for it to fit, I had to cut bait. I just couldn’t get it. I knew it would be tight, but I thought it could squeak it in. I cannot.
So I spent today figuring out where to put them. I actually like this better, since the batteries will be inside and I need less $8.00/foot battery cable.
They fit a bit better turned 90 degrees and in two rows of two, vs all online like in the pic, so I’ll do that. I’ll build a raised floor above them and a nightstand cabinet to hide my charger and DC power distribution. A/C distribution will be in that black box in the foreground, recessed into the panel there.
I have a camping trip in the 22nd of this month. Going to get the power, water and beds installed so we can talk the MH vs a tent. I need to install my new Air Cons too, so it will be good to test those. Nothing like a looming deadline to motivate your ass!
So I spent today figuring out where to put them. I actually like this better, since the batteries will be inside and I need less $8.00/foot battery cable.
They fit a bit better turned 90 degrees and in two rows of two, vs all online like in the pic, so I’ll do that. I’ll build a raised floor above them and a nightstand cabinet to hide my charger and DC power distribution. A/C distribution will be in that black box in the foreground, recessed into the panel there.
I have a camping trip in the 22nd of this month. Going to get the power, water and beds installed so we can talk the MH vs a tent. I need to install my new Air Cons too, so it will be good to test those. Nothing like a looming deadline to motivate your ass!
OP
Here's how we're looking so far. I'll do a short drawer up top, and a false front cab door from the floor to the drawer. The PO had a shoddy hinged door and every time I needed to get in there, I fought that stupid thing. It was ALWAYS in the way....there is only 27 inches between the bed frames, and I'm not a small guy (6'2" and about 220 lbs). So, being able to remove the door face entirely will be nice. I'll use some rare earth magnets to hold it on. I will probably make the upper section removable too, just in case I need to pull the inverter out the top or I want to look down on my connections that are positioned on the level above the batteries.
The table top will include a couple cell phone charging ports and a place to plug in reading lamps. Having the drawer there will be good too, so we can store our nighttime "stuff" like bite splints, ear plugs, and the other stuff you need when both parties in a couple snore, and you need to choose between drowning out the noise, or smothering them with a pillow, LOL.
The table top will include a couple cell phone charging ports and a place to plug in reading lamps. Having the drawer there will be good too, so we can store our nighttime "stuff" like bite splints, ear plugs, and the other stuff you need when both parties in a couple snore, and you need to choose between drowning out the noise, or smothering them with a pillow, LOL.
My friend brought his GMC up to date by putting a Cadillac engine in it along with coil spring suspension.
OP
Coil spring in the back? Be interested to see pictures. Do you know if he's on the GMCmotorhome.org forum?
I ask him today and he just put a coil spring and end caps which he made in the place of the stock horizontal air bag in the rear. Of course vertical coils in the front.
OP
OP
Spent a few hours today on the motorhome, Got my first piece of the Victron stuff mounted!
This will be the back wall of our nightstand. It will come forward about 24 inches and my batteries and the rest of the DC power distribution will be there. My AC power will come forward and be located in the lower rh corner of the picture. There is a bit of open space where the air compressor lives. The LH side of the photo, where it looks like there is a lot of open room is where the 40 gallon Fresh Water tank lives.
It doesn't seem like much, but this is a BIG step forward in the process. Getting those half walls in position and anchored to the floor and back wall properly was a pain. Nothing is true and plumb in this rig...The floor is flat, but that's about it. Every wall is curved so measurements are tough. Trying to build off the floor, only, means I need another hand. I should probably go get one of those lasers that projects level and plumb lines off the floor, so I can make the rest of this project go more easily.
This will be the back wall of our nightstand. It will come forward about 24 inches and my batteries and the rest of the DC power distribution will be there. My AC power will come forward and be located in the lower rh corner of the picture. There is a bit of open space where the air compressor lives. The LH side of the photo, where it looks like there is a lot of open room is where the 40 gallon Fresh Water tank lives.
It doesn't seem like much, but this is a BIG step forward in the process. Getting those half walls in position and anchored to the floor and back wall properly was a pain. Nothing is true and plumb in this rig...The floor is flat, but that's about it. Every wall is curved so measurements are tough. Trying to build off the floor, only, means I need another hand. I should probably go get one of those lasers that projects level and plumb lines off the floor, so I can make the rest of this project go more easily.
So much work that doesn't get seen after it's done. You know it's there though....impressive progress!
OP
Got some battery cables made up tonight. Bought one of those fancy wire crimper for this project. I was never happy with the hydraulic one from Amazon. After reading this article on marine how to, I decided to up my game a bit
https://marinehowto.com/making-your-own-battery-cables/
I bought the FTZ crimper on Amazon and a bunch of power lugs from CE auto electric supply. Got my wire from West Marine, since I have one local and shipping copper is $$$. Anyway, to supply the max power from the batteries and inverter, I calculated I needed 2/0 wire. The conductor is about 3/4” in diameter! Here is what a cable looks like, crimped, but before heat shrink
And the cables I made tonight. These will connect all my batteries in parallel, to get my four,12V 100 amp-hour batteries up to a 12V 400 Ah pack.
The next bit of wires will have to be made in situ, as I don’t really know where everything is going quite yet.
https://marinehowto.com/making-your-own-battery-cables/
I bought the FTZ crimper on Amazon and a bunch of power lugs from CE auto electric supply. Got my wire from West Marine, since I have one local and shipping copper is $$$. Anyway, to supply the max power from the batteries and inverter, I calculated I needed 2/0 wire. The conductor is about 3/4” in diameter! Here is what a cable looks like, crimped, but before heat shrink
And the cables I made tonight. These will connect all my batteries in parallel, to get my four,12V 100 amp-hour batteries up to a 12V 400 Ah pack.
The next bit of wires will have to be made in situ, as I don’t really know where everything is going quite yet.
OP
Been playing with the motorhome again, made some real, tangible progress last weekend with the power system. Got my batteries mounted and secured, figured out my “doghouse” to hide all that stuff, and started working on the layout of all the components between the batteries and the inverter.
Cardboard mock up for female approval. The box on top will look like the rest of the cabinets we have in the coach. The bottom will be upholstered like the side walls below the bed were and will be again.
Batteries in their new home and wired in parallel.
And the next layer to protect and distribute 400 amp hours worth of Li-Ion batteries
Had to order a couple 90 degree terminals to get the wires up on the tray a bit easier. None of this stuff is screwed down yet, so this is just a first pass arrangement. I’ll keep playing around with it until I get it nice and neat because 2/0 wire doesn’t have a very tight bend radius!.
Cardboard mock up for female approval. The box on top will look like the rest of the cabinets we have in the coach. The bottom will be upholstered like the side walls below the bed were and will be again.
Batteries in their new home and wired in parallel.
And the next layer to protect and distribute 400 amp hours worth of Li-Ion batteries
Had to order a couple 90 degree terminals to get the wires up on the tray a bit easier. None of this stuff is screwed down yet, so this is just a first pass arrangement. I’ll keep playing around with it until I get it nice and neat because 2/0 wire doesn’t have a very tight bend radius!.
OP
Getting close to having power back in the ol motorhome. I have the batteries all connected to the switches, fuses, etc. and all that stuff is mounted to my board. The final piece of the puzzle (for now) is to get my DC - DC charger installed. I need to run a big wire from the alternator to the back of the coach. There is one already there…but I don’t think it’s big enough. My charger is a 30 amp, so it’s gonna need a decent piece of copper to go 30’ish feet at a 3% loss rate and 12V nominal voltage.
I’m pretty happy with how this is turning out. My hinge idea works beautifully and the layout is pleasing to my eye so far. It’s going to get busier, but I’m trying really hard to not get impatient and keep my wires nice and neat.
I’m pretty happy with how this is turning out. My hinge idea works beautifully and the layout is pleasing to my eye so far. It’s going to get busier, but I’m trying really hard to not get impatient and keep my wires nice and neat.
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I saw this clean example on the freeway.the gmc motorhome rally banner was interesting
OP
Two weeks ago, there was a big shindig at the Shiawassee Country fairgrounds for the 50th anniversary of the first motorhomes that GM built. They had a get-together at M1 motorsports park, which is the site of the old assembly plant they were built in. I assume that was someone heading home from that event.
https://m1concourse.com/gallery/#gallery[photonic-flickr-set-72177720311501827-1]/53217991233/
OP
Ooof.
The electrical on my coach is awful. I removed the 6 gage wire that ran from the main fuse and isolator for my factory installed house battery yesterday. Since I have a coachman, there are also two other circuits tied into that same post.
Those all came out, because of some nasty surprises. One of the two coachman circuits (used in the kitchen) had rubbed bare on the frame, which could create a dead short. None of the wires were loomed or properly contained…only zip tied to the fuel supply line.
I found this fuse holder, added to the factory harness.
And it was spliced in by twisted two wires together and taping them!
Further, the blue wire carried on to the NEGATIVE post of the isolator! I don’t have any idea what that circuit was supposed to power, but it ain’t gonna work like that.
I found this nice splice in the back of my coach. This is the main supply for the DC house system, for what it’s worth.
For those paying attention, you’ll notice a 6 gage wire crammed into a yellow ring terminal…(10-12 AWG size) and a bunch of broken strands. It’s no wonder I have had trouble with my house DC. Oh…that junction wasn’t made on a chassis post or screw terminal or any of the other proper ways to do that. Nope, just that bolt and nut, dangling free in space, wrapped in tape.
I’ve also found two other wires that were clipped in half or broken along their journey to the back of the coach. I believe they are wires from the remote panel for the generator. As I strip more of this old stuff out, I’ll see what needs to be replaced. I am going to use blue tooth level sensors for my waste, propane, and fresh water tanks, which will communicate with my Cerbus. So a long of that wiring will go away.
It’s a wonder this thing hasn’t burned to the ground. I grouse about the cost of all the copper I’ve had to replace in this thing, but when I think about the condition it’s in correctly…it’s cheap insurance going forward. This is one of those areas where the cost of a poor job is way higher than the cost of doing it right. If this coach catches on fire, it’s going down. I’ve known of a few that have burned, and only one of them made it enough to be rebuilt. The rest melt back down into their elements.
The wife and I are heading to botrangers surplus on Friday this week too. I pulled the fridge and oven in anticipation of that. Still trying to decide if I want to stay with an absorption style fridge, or go DC compressor. We’re also installing an induction cooktop vs the range. We have a convection microwave oven if we ever feel the need to use an oven. Hopefully, we can score a good deal on a couple new appliances.
The electrical on my coach is awful. I removed the 6 gage wire that ran from the main fuse and isolator for my factory installed house battery yesterday. Since I have a coachman, there are also two other circuits tied into that same post.
Those all came out, because of some nasty surprises. One of the two coachman circuits (used in the kitchen) had rubbed bare on the frame, which could create a dead short. None of the wires were loomed or properly contained…only zip tied to the fuel supply line.
I found this fuse holder, added to the factory harness.
And it was spliced in by twisted two wires together and taping them!
Further, the blue wire carried on to the NEGATIVE post of the isolator! I don’t have any idea what that circuit was supposed to power, but it ain’t gonna work like that.
I found this nice splice in the back of my coach. This is the main supply for the DC house system, for what it’s worth.
For those paying attention, you’ll notice a 6 gage wire crammed into a yellow ring terminal…(10-12 AWG size) and a bunch of broken strands. It’s no wonder I have had trouble with my house DC. Oh…that junction wasn’t made on a chassis post or screw terminal or any of the other proper ways to do that. Nope, just that bolt and nut, dangling free in space, wrapped in tape.
I’ve also found two other wires that were clipped in half or broken along their journey to the back of the coach. I believe they are wires from the remote panel for the generator. As I strip more of this old stuff out, I’ll see what needs to be replaced. I am going to use blue tooth level sensors for my waste, propane, and fresh water tanks, which will communicate with my Cerbus. So a long of that wiring will go away.
It’s a wonder this thing hasn’t burned to the ground. I grouse about the cost of all the copper I’ve had to replace in this thing, but when I think about the condition it’s in correctly…it’s cheap insurance going forward. This is one of those areas where the cost of a poor job is way higher than the cost of doing it right. If this coach catches on fire, it’s going down. I’ve known of a few that have burned, and only one of them made it enough to be rebuilt. The rest melt back down into their elements.
The wife and I are heading to botrangers surplus on Friday this week too. I pulled the fridge and oven in anticipation of that. Still trying to decide if I want to stay with an absorption style fridge, or go DC compressor. We’re also installing an induction cooktop vs the range. We have a convection microwave oven if we ever feel the need to use an oven. Hopefully, we can score a good deal on a couple new appliances.