1978 Blazer FWC

brian90744

American Trekker
The blue battery isolator on right fender has 3 termals. the center is for the alternator, the left is to battery. no right is required, unless you have 2 batteries. Just fyi=brian
 

Rush4x4

New member
The blue battery isolator on right fender has 3 termals. the center is for the alternator, the left is to battery. no right is required, unless you have 2 batteries. Just fyi=brian

I'm running two. One for the camper, one for the truck.
 

zoomad75

K5 Camper guy
I like the slots. Keep them if you can. They fit the style of the 78 and the camper well.

Getting back to your charging problem, I'm running a similar alternator on my 5.3. Mine is set up to one on 1 wire. But for the life of me I can't remember how I hooked it up. I'll have to look at it tomorrow.
 

zoomad75

K5 Camper guy
While I was working on mine this afternoon I double checked my connector to the alternator. I have 1 circuit going into the plug. The plug has four terminal locations, 1 large and three smaller. The single wire is connected to the first small terminal next to the large terminal. That should be marked as terminal "I" for ign. Your original alternator connector would have had that circuit there, just transfer it to the pigtail for the new alternator and connect it to the correct terminal and it should work.
 

Rush4x4

New member
While I was working on mine this afternoon I double checked my connector to the alternator. I have 1 circuit going into the plug. The plug has four terminal locations, 1 large and three smaller. The single wire is connected to the first small terminal next to the large terminal. That should be marked as terminal "I" for ign. Your original alternator connector would have had that circuit there, just transfer it to the pigtail for the new alternator and connect it to the correct terminal and it should work.

Got a pic?
 

zoomad75

K5 Camper guy
I never got around to getting a pic of my plug, but here's one off of the net. My single wire goes into the first small terminal next to the large terminal in this pic. Pretty easy.

longyue-20-Kit-CS130-CS121-CS144-Alternator-Connector-Plug-Delco.jpg_640x640.jpg
 

Rush4x4

New member
I never got around to getting a pic of my plug, but here's one off of the net. My single wire goes into the first small terminal next to the large terminal in this pic. Pretty easy.

Thanks for the info. Pretty sure I tried it like that. I've been traveling and haven't been able to look at it. So you only have the one wire? Everything I've read states that I need to connect that large lead on the far left of the image to the alternator output as it's a "sense wire" or excitor. The other wire that will be used is used for the gauges; one for if you have an actual gauge, and the other if you have a indicator light. The only thing I haven't yet tried is actually taking the large red lead and running it directly to the positive side of the battery. Maybe it isn't actually hooked up where I think it is on the other end (I have a hard time contorting myself into a position to see it well, and the headers are right in my way).
 

zoomad75

K5 Camper guy
I'd have to study the schematic for my 91 to know where the wire at the alternator came from. I want to say it's coming from the gauge.
 

Rush4x4

New member
Pretty sure I got it figured out. The isolator I have has a diode for each battery, so there's no voltage to sense at the back of the alternator output because the electricity only flows one way, therefore the alternator won't charge. If I hook the sense wire directly to the positive side of a battery, it'll charge. Anyway, I already ordered a different isolator; one with jump-start capability, and this isolator is only rated to 120 amps anyway. Nice to figure it out, though and I appreciate your help, Zoomad.
 

Rush4x4

New member
Funny story. I'd been searching specifically for a Blazer or Ramcharger/Trailduster with a camper for years; since at least 2012 (though I remember seeing them and thinking it would be nice to have one back in 2009 or so). Anyway, I was looking for some family pictures I had stored on an ancient laptop, and stumbled into a Word document that had some photos I'd saved from Craigslist. The last ad I'd saved on the document was the actual ad placed by the 2nd previous owner. It looks almost exactly like I got it, except it still had it's refrigerator, the cabinet hadn't been modified, it had a different heater, and it had a 5 gallon water tank.

The ad states: "I have a 1978 K 5 blazer for sale. I have owned it for 6 years and it has never let me down. The engine, transmission and transfer case have less than 10k on them. The engine is a 350 with 4 bolt mains. It has an edelbrock intake and carb, Headers, and accel super coil, 4 core radiator, dual battery set up, power steering, power brakes, power windows, and power locks. aM/FM/CD with remote speakers. It has a slide in camper made by Four Wheel Campers. The camper has a gas fridge, two burner stove top, 10 gallon water tank, gas radiant heater. New carpet with pad. 2500 watt inverter and camper battery volt gauge. Tire and wheel combo - 33 x 12.50 with Alcoa aluminum wheels. The transfer case has the part time kit and front lock-out hubs are installed. New springs were just put on before I purchased. I just installed newer seats out of a 1998 Dakota. Now the seats are very comfy and completely adjustable. Huge upgrade over factory seats. Any more questions please call. Motivated seller need to go to new home. Zach"

Here's a few pictures that accompanied the ad in 2012:
SmartSelectImage_2018-06-17-18-34-44-953x696.pngSmartSelectImage_2018-06-17-18-36-37-955x706.pngSmartSelectImage_2018-06-17-18-35-02-955x704.png
 

zoomad75

K5 Camper guy
That's pretty funny you snagged the ad for the eventual rig you bought years later. Cool to see the little changes made too.
 

Rush4x4

New member
Charging problem fixed. Changed out the battery isolator for a solenoid type smart charger. It's got less parasitic loss, is rated to 200 amps, and I can wire in a switch that allows me to jump start myself using the camper battery if necessary. 20180704_135059-1651x1238.jpg
Ran into another issue when I upgraded the accessory drive: I have a constant squeal from the serpentine belt. I've already isolated the problem, though. It's misaligned. These heads have only one accessory bolt hole on the end of the passenger side cylinder head, so I made a piece that braces from the intake manifold to the back of the alternator bracket, but it's just not quite right. It's pretty solid; it doesn't flex/move. But it's just not right. I don't feel comfortable drilling another hole in the end of the cylinder head, and I don't really want to change them out altogether, either. I keep waiting for a L29 454 to pop up on Craigslist that I can trade stuff for (my Blazer budget is pretty much exhausted for a while!).

Also, changed out a couple of the lugs on the rear axle and put the new wheels/tires on. Spent a while grinding the brake caliper on the passenger side and it spins freely but I can still hear just the slightest rub when driving it. I still need to take them off and grind some more. After all, I'd like to be able to rotate the tires whenever I want to.20180704_135203-1651x1238.jpg20180704_135259-1651x1238.jpg
And lastly, I got both seats in and got them wired. They're super comfy, I just need to get some seat covers for them to hide the cracking and the split seam on the driver's seat. 20180704_135221-1651x1238.jpg
 

zoomad75

K5 Camper guy
Good work. I love the slots. I would kill to find a set of 8 lug slots for mine.

As far as the missing bolt hole in the head, you can use the bracket itself as a template. Go slow and keep checking depth.

It's time for you to bring it back to CO so it can get out in it's natural habitat...
28294260077_51d642aa9f_b.jpg
 

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