Big John: 1972 C30 2WD dually w/ 11' dump bed

Picked up radiator and was told they were just chasing pinholes after pressurizing, so that one will be tossed.
Ordered a new one and received an old core that leaked, so had to take it back. Finally got one that holds water; installed it and hooked everything up and topped it off.
Toolboxes are mounted and battery cable ran from starter to the battery box.
Gauge cluster connected and installed and wired the dome light & fuel sending unit.
Steering column, wheel & horn button installed (tilt column > non-tilt).

Started testing the wiring and hit a snag:
The Good...
headlights (low & high beams) work
LED bar works
aux bed lighting works
parking lights work (minus one bulb)
gas gauge works
reverse lights/camera works

The Bad...
dome light doesn't work (flashes when I turn the lights off?)
battery gauge reads ~11V (running off my F250 @ ~14V)
turn signals don't work
starter clicks when I turn the key to ignition, but doesn't turn over (nothing happens at the run position)
jumper cables I was using started getting real warm

The Ugly...
Putting all the wiring in loom before testing since I was taking my time making sure the wiring was 'right'
Laughing like a crazy person while packing up and leaving knowing if I didn't I'd start throwing/breaking things
 
In light of you & Ron, working on Heirlooms, I snapped this pic today, near a jobsite. Guessing 68 - 72 C-50? I think it was farther out in a field, 3 months ago. Maybe I was wrong. Front tire is flat, but it could have been pushed, pulled, or even driven. It's probably for sale, if anyone is interested. South Point/Belmont area.
 

Attachments

  • IMG_20200506_112806570.jpg
    IMG_20200506_112806570.jpg
    83.9 KB · Views: 263
rodney eppes said:
In light of you & Ron, working on Heirlooms, I snapped this pic today, near a jobsite. Guessing 68 - 72 C-50? I think it was farther out in a field, 3 months ago. Maybe I was wrong. Front tire is flat, but it could have been pushed, pulled, or even driven. It's probably for sale, if anyone is interested. South Point/Belmont area.
Click to expand...
Tagging @CarolinaHD since he seems to like the >1 ton Chevy/GMC platforms
 
CarolinaHD said:
Well just a look couldn't hurt... :rolleyes:

@rodney eppes what's the address or road it's on? Could probably find it on google earth
Click to expand...
Goggle comes up with 299-101 Breezewood Dr. Belmont NC 28012. On Satellite, you can see a barn, where the truck is. I'd say the Nice farm house across the street, is the owner. My job site was further down on the River.
 
More progress over the weekend:
New radiator is still holding water, so that's good
Put more bolts in the toolbox mounts
Horn button wasn't working, so disassembled the steering wheel, fixed and reassembled...finally works after 10+ years!
Found a bad ground on the front passenger parking/turn light...added a ground wire to the bulb socket on both sides to fix current & possible future problem
Dome light had a bad connection, cleaned & greased everything & its back to working and works off the door jamb switch wiring too
Battery gauge is working, but the starter solenoid was shorting out so that's why it dropped to 11V when 'ON' (also explains why the starter wasn't working & warm jumper cables)
The bad ground fixed the turn signal issue and I also de-pinned the brake switch output from the steering wheel harness to keep the turn signals off while braking

To Do:
Temp warning light comes on at 'RUN', but flickers so I'll have to find & fix that loose connection.
2 of the cab clearance lights flicker, so I'll clean/remake those connections again.
Terminate the battery cables in the toolbox.
Retest wiring to headache rack
Test the oil pressure, speedo & tach gauges/connections (thought about bump starting it, but really want to test everything together)

Head Scratchers:
Temp gauge is pegged on 'H' and the temp sensor is reading 1.5 ohms at ~50*F; temp gauge falls to 'L' when I unplug the wire (makes sense)...hopefully I didn't buy a sensor that increases resistance with heat!
This sensor/switch has two terminals 'R' & 'G'...I'm thinking 'G' is sensor/gauge & 'R' is switch/relay? I swear I tested the sensor and the resistance on 'G' dropped from ambient temp in the shade to holding it in my hand and the 'R' stayed open no matter what. Planning to check the resistance after its running for a while in case the sensor is bad.

Picked up a starter on Saturday and that solenoid was shorted out too, sent it back & picked up another Sunday...same issue. Plan is to pick up another in Youngsville today and keep sending them back until I get one that works.
UPDATE: starter #3 solenoid was shorted out & I even had them test it...didn't move or make a noise & the tester just said 'FAILED'. #4 will be here tomorrow...hopefully there aren't 3-4 bad ones in a rotation between me & the warehouse!
Somebody please correct me if I'm wrong...3 connections on the starter; battery, 'R' & 'S'. Battery is self-explanatory, 'R' is a purple wire from the ignition switch in the 'RUN' position & 'S' is a pink wire from the ignition switch in the 'ON' position. The way I see it is when you crank the engine, the 'R' terminal gets power, engages the starter & gives power to the 'S' terminal which basically backfeeds the ignition circuit. So if the 'S' terminal is grounded to the case, I'd be grounding the battery in the 'ON' & 'RUN' positions right?

UPDATE#2: Finally picked up a starter when the older guy was working...and got a weird look when I said this was the 4th one in 4 days. He tested the first one I bought/kept trying to swap and it worked like a champ! Turns out I wasn't thinking clearly, and now I feel like an idiot...'R' is Run/ignition/pink wire & 'S' is Start/crank/purple wire....not sure what I was thinking (I blame it on cabin fever/the 'rona). So apparently I wired the ~50 year old one & the first one backwards and the younger people behind the parts counter didn't know any better & just went off the testing diagram which the old guy said looked off. Would have been cool to keep the OEM starter, but trying to look on the bright side the new one is much lighter & weight reduction = race truck!
 
Last edited:
Turns out the starter I kept exchanging mounts to the engine block & I needed one that mounts to the bell housing (really felt like an idiot at this point). Checked online & the only store with the correct one was ~20 miles down the road...so an hour later I'm back from the parts store with the correct starter & had to shave the cast flange down to fit. Finally got it bolted on and wired to hit the key and hear 'click'. Cleaned up the bad ground connection and the motor turns over like a champ (amazing how it works when its wired correctly)! Checked the oil pressure gauge for any leaks, hooked up ignition to the coil and it turned over for days, but didn't fire. At this point I was covered it dirt, leaves, grit & grease and tired from sliding under the truck to test fit the starter several times. Counted it as a win the starter was working, packed up & headed out for a hot shower & cold beer. I'm thinking since I didn't pull the ignition wire off the coil when I was testing everything I may have burnt up the points? If so, that'll be a good time to upgrade to HEI!
 
rodney eppes said:
I use my $2 blue tarp, or a blanket. Anything to stay out of the Crap. And I Slide better too!
Click to expand...
I'm going to grab one to throw in the toolbox for future use. The old piece of carpet I was using didn't do much!
 
After some troubleshooting, the coil was only getting 8-9 volts and the ballast resistor was reading 6 ohms. Paralleled the OEM resistance wire (~2 ohms) to get ~1.3 ohms which put the coil at 10.9 volts while running and I've got the correct one on the way. Took it for a celebration lap/shakedown run around the property and the brake pedal feels spongy and the tach doesn't work. Need to work on those items and looking up the temp sensor I believe it increases resistance with heat (opposite of OEM)...guess I'll be getting another one.

After everything electrically is working 100% and the brakes are bled again/feel better I'll move on to:
exhaust
gun rack
center console/cupholders
heater/defrost hoses
paint the bed black
replace hydraulic hoses
hydraulic cylinder brace
rear hydraulic wet lines
 
I never would have guessed it, but apparently somebody else in Albemarle was working on an old ignition system and picked up the 1.2 ohm ballast resistor I ordered (didn't give my name/number because what are the odds?). Got one this morning and swapped it in and put the OEM resistance wire in my spare parts box. For anyone else looking the OEM resistance wire was 2 ohms, Standard P/N# RU38 is 6 ohms (not in any documentation I found) and Standard P/N# RU37 is 1.2 ohms. Using RU38 put the ignition voltage at ~8 volts (too low to fire the coil/plugs); using RU37 put the ignition voltage at ~11 volts.
Bled the brakes yesterday and got some air out at all 4 corners and now it'll lock up the tires on gravel & grass....I'm going to bleed them again just to make sure no more air is trapped in the system.
Got the courage to put it on the road for the first time in ~10 years for a whopping 3 mile loop! Everything went great for a quarter of a mile and it started popping and bucking under heavy throttle so I eased off and turned on the hazards. Ran well at light throttle for another quarter mile and then every time I pushed in the clutch the engine would die until I changed gears then it would fire up again. Thankfully my test loop was all right hand turns and I only had to do a rolling stop once. Best guess is some trash or varnish was caught in the fuel line/pump/carb? Added a bottle of sea foam to the gas tank with some more gas and it ran better today...revving it hard would shoot flames out of the exhaust flange/donut gasket, so that'll get some attention soon!
I was planning on using the switched ground for the dome light to toggle a relay for a courtesy light I'm adding in the bed, but that wire reads 6V when 'off'. That's just enough voltage to pull in the contact on a 12V relay, but not enough to latch it and feel the 'click'. So that will most likely be abandoned since I've got a work light switch already ran and working.
Picked up some flat bar to make a gun rack since I can't find one I like and OEM ones are $$$ (if you can even find one).
 
I made it back Sunday and swapped batteries since the old one was weak...spins over quick & fires right up now! Checked the fluids, lug nuts & axle bolts and cut the passenger exhaust pipe where it drops below the frame and put it on the road...ran way better than last time! Drove to Walmart to top off on fuel and got a text from my dad asking 'how its running?' So I drove it through town (lots of looks) to my folks' house. My brother was there & needed some stuff at his place so we extended the shake down run and then back to town and finally back to grandpa's.

Issues:
The exhaust is deafeningly loud! We had ear plugs in and were still shouting at each other from 3-4' away. I'd like to get the exhaust done before grandpa turns 90 this month although he probably won't want to ride in it.
The fuel gauge doesn't work even though the connections test good. Hoping its a stuck needle or bad resistor...either way the cluster will have to come out.
The tach works when it wants to which is odd since all the connections are tight. Hoping its bad, but I doubt it has a warranty.
Temp sensor is bad & I found out the switch closes at 275* so I'm looking for a different one.
Driver side front parking light/turn signal loses ground. Made me laugh since that one worked before & I added a ground wire as a preventative fix...could be a bad socket connection.
Need an O/D transmission...the one in VA is a Spicer 4054 series (5 speed, but 5th is 1:1)

Thoughts on exhaust:
Option#1) Dual exhaust and turn out/down after the toolboxes
Option#2) Wye the exhaust and turn out/down after the driver side toolboxes (this would avoid the PTO on the passenger side)
Option#3) Turn up after the cab & rock some tractor flaps
~#3 was inspired while walking around Tractor Supply. Also ran into the guy that I want to make my hydraulic lines and gave him a heads up.
 
Well they say bad things comes in threes so idiotic moments must come in threes too! The temp sensor/switch I bought said in the description 'Temp sender with Light'...so I assumed (we all know that saying) that with 2 terminals one would be for the gauge and another for the light which was exactly what I wanted. After getting inconsistent resistance readings I called the manufacturer to get a breakdown for all their 2 terminal temp switches and compare it to the OEM temp sensor chart. Below is that breakdown for TS15, TS46, TS47, TS49 & TS51 as well as the resistance specs for TS6. It turns out the 'G' contact opens & the 'R' contact closes at certain temps (+/- 5%) on the temp switches.
TempCurve.jpg TempSensor&Switches.jpg

Long story short, I've now got an OEM temp sensor for the gauge and a TS46 switch for the idiot light since 275F is much higher than I'd want to know I have a temperature problem! I also put heat shrink on the 'G' contact so you can't plug the wiring into the wrong terminal.
20200614_161251.jpg

Got the exhaust kit & mufflers spec'd out and plan on running the passenger side over to the driver's side and then running both along the frame and dumping after the toolbox. Passenger exhaust was easy to remove, but the driver side has one stud/nut seized and its fighting me. Once its out I can make sure everything will fit how I want and place the order. You can see how kinked the pass side was when it was modified to clear the PTO.
11465.jpeg

Fuel gauge ended up being a cracked/sunk float (less than 6 months old)...replaced it with a plastic one from a Jeep (Omix-Ada 17729.01) and it snaps right in. Fuel gauge still didn't work even though the readings were right so I pulled the cluster and removed the ignition jumper I added for the tach. That did the trick, so I'm wondering if something in the tach interferes with the fuel gauge or if the tach is bad? Gonna dive into that this week and hopefully reassemble/test this weekend.
20200606_165524.jpg

EDIT: Forgot to mention that I had a bad ground connection on the driver's side parking light socket. Cleaned the oxidation off, re-soldered & its back to working!
 
Last edited:
Turns out the tach was shorting to ground internally. Interesting to see that the external wiring is ~12awg, but the internal wiring is ~18awg, but you can see the heat shrink on the ignition terminal was pierced by one of the studs and the overheated resistor. I was able to change the tach out for a new one & got it mounted in the cluster, but not installed in the truck/tested yet.
20200616_194712.jpg 20200616_194655.jpg

Also got the driver's side exhaust off and the new exhaust kit, mufflers & donut gaskets ordered. Hopefully that all goes together like I'm planning!
 
Got the dash installed and now all the gauges are working!
Drained the coolant & installed the correct temp sensor. Hit a snag when the temp switch will not thread into the water pump (different threads) so I'm looking for another spot.
Exhaust kit & mufflers were delivered Saturday afternoon so I spent Saturday night & most of Sunday modifying the tubes. I knew the passenger side would have to be changed to crossover & run down the driver's side, but the only tube I didn't have to shorten, lengthen or pie cut was the driver's side header pipe! Still throaty and louder than I'd like, but running through some glass packs, what do you expect? I just have to get the hangers/clamps installed and make up some tailpipes and it'll be good enough to not go deaf!

20200628_205853.jpg
 
I've got all the metal to build some cupholders and a rifle rack I just need to find something better than flatbar for the long guns to rest on and I wouldn't mind if the temp would drop ~20 degrees!
I've heavily tacked the nuts for the door switches and hood light and got everything wired so that should be all the electrical work done until I finish off the headache rack with aux lighting.
Exhaust has been finished & its been on a few shakedown runs around Badin/Albemarle/Aquadale without an issue. Also ran it by Mauney's Feed Mill and it rolled across the scales at 6,300#.
My brother loaded his 275 gallon smoker on it with a bed full of wood to test it out on 100 chicken halves before building a 2nd one (seemed easier than using a wooden trailer). Also got to use the dump bed to unload it!

Drove it to one of my deer plots this weekend when I was in town and shut it off to check the feeder & camera. 5 minutes later and it wouldn't spin over fast enough to fire! Luckily it was only a short walk to my grandpa's house to borrow his truck & jump it off...best I can tell the battery has a dead cell so I'll have to get another one. Other than that, its pretty much done until it cools off when I'll work on the heater/defrost tubes.
 
Last edited:
CarolinaHD said:
Keep at it!
Click to expand...
Planning on it, but the last few things aren't much...unless I can get my hands on a 5 speed and/or a higher gear set! Already called my battery hookup & he's looking into some more freebies.

'To Do' list is getting shorter:
Fab up cup/phone holders & gun rack
Trim the headache rack, weld some 2"x2" to the top & mount/wire the aux lights
Get the heater working, install defrost hoses, then I can mount the glove box liner & door
Go through the hydraulics, add rear wet lines & fab up a brace to work on it with the bed raised
Figure out the choke return spring & add the temp switch
Fab up a grill & in-cab hood release
Paint the bed black & possibly paint the roof of the cab white?
 
Working on the deer plots & topping off my feeders this weekend and wanted to stretch its legs to Concord & back. Swapped in a battery from my F250, hit the switch and it spun over but wouldn't fire. Opened up the hood to fuel on the intake manifold, wet plugs and fuel dripping out of the carburetor. :shaking: Pulled the carb and I'm trying to find the right gasket/rebuild kit for a 2 Jet Rochester.

Also started looking in to what all is needed for a 5 speed swap. Saving myself time in the future with a link dump:
NV4500 Transmission Info, Conversions, Reviews
New Venture Gear 4500 transmission - Wikipedia
Switching my sm465 to a nv4500 in a 1969 Chevy C20 - The 1947 - Present Chevrolet & GMC Truck Message Board Network
Installing The NV4500 5 Speed Overdrive Transmission In The C-30 - The 1947 - Present Chevrolet & GMC Truck Message Board Network
Nv4500 identification and conversion help needed - The 1947 - Present Chevrolet & GMC Truck Message Board Network
NV4500 LD or HD - The 1947 - Present Chevrolet & GMC Truck Message Board Network
NV4500 swap installed and rollin! - The 1947 - Present Chevrolet & GMC Truck Message Board Network
NV4500 swap help - The 1947 - Present Chevrolet & GMC Truck Message Board Network
 
I rebuilt my 1 barrel Rochester 3 times and it kept leaking. Threw in the towel and bought a reman from rockauto and haven't looked back.

I'd look into a reman or swap in a new one.
 
CarolinaHD said:
I rebuilt my 1 barrel Rochester 3 times and it kept leaking. Threw in the towel and bought a reman from rockauto and haven't looked back.

I'd look into a reman or swap in a new one.
Click to expand...

I just may end up throwing a new one at it! Haven't even had a chance to take it all apart this week...on-call so far this week has been hell!
Funny thing is I stumbled on a youtube video of boosting with a blow through carb and its got the 'Wanna go fast' part of my brain going. Think I'll save that for the next sbc vehicle that's 2 years older & half the weight!
 
I hadn't been keeping up with this thread, but I was going to say the r and g on the temp switch sounded like it was for a car with lights. R goes to red hot light, g goes to green cold light on lots of 60s cars that didn't have temp gauges. My 67 Ford Fairlane is like that. Cold light is on below 100 ish degrees, hot light comes on like you'd expect.

Lots of gm temp switches are set to 260 to 275 because they screw into the head usually and coolant temp is actually warmer there near the exhaust ports. 275 in the head is about 245 to 250 at the thermostat, because it's still mixing with "cooler" water that isn't near the ports. And at 13 to 15 psi with proper antifreeze mix water won't boil til 275 or higher. An engine isn't technically overheated until the coolant is boiling, as long as it's still a liquid 275 coolant is cooling the much hotter metal, which around an exhaust ports can be way hotter. I understand the wanting the hot light to come on sooner, it does give a safety buffer, but that is GM's reasoning.
 
Back
Top