Re: "Papa Smurf" - 1966 GMC 1500 Custom
 

If the other bolts are already removed, I would try and use a long rod and slip it in the clutch disc hub all the way through and into the pilot bearing. Then see if the disc can be moved away from the bolt, it might move enough to remove the remaining bolts.

Re: "Papa Smurf" - 1966 GMC 1500 Custom
 

That worked to get one of the troublesome bolts out. For the last one, I just pried the pressure plate away from the flywheel, yanked out the clutch, and then had enough clearance to remove the bolt. The pressure plate is not salvageable. Not because I damaged it, though. It is (was) new, but it is badly grooved and burnt. The clutch plate itself doesn't have much meat on it. Looks like it got burned up. Not a problem though. Clutch kits are easy to source.

Another update: Finally got around to relocating my idler arm. Replaced to old idler arm that was on the bracket first. Got it torqued to the drag link, got the drag link torqued to the steering box. Then I got out my level and began measuring. Got the drag link level with the crossmember and got it straight. Drilled two holes and bolted it in. I can turn the wheel lock-to-lock without the drag link rubbing on the crossmember. Once that was done, finished up with some new tie rods and fresh grease.

Also want to share that I got my hands on the "Custom" badges. I managed to get two of them from AspenAutoAZ. The studs are broken off the back, but I think I can repair them.

Re: "Papa Smurf" - 1966 GMC 1500 Custom
 

Or you can use 3/32" thick double-stick tape, trimmed to fit the profile...not quite as much work as creating locator studs for pot metal.

Re: "Papa Smurf" - 1966 GMC 1500 Custom
 

No pictures today. Just another update.

Finally bought a belt for the power steering system. Also changed the brackets for my generator so the belt would be on the second (outer) pulley groove. The power steering and generator are now independent of each other. If a belt snaps, I'll lose either power steering or the generator. Nothing else. I do have plans to eventually convert to an internally regulated alternator. I have the parts, but not the motivation. Lol.

Also bled the power steering. It was not a clean process. It hiccuped while I was doing it and made a lovely puddle of oil on the crossmember... But, at least I can turn the wheel with one hand now. I'll monitor the fittings over the next few days to make sure I don't have any leaks. So far though, everything looks good.

Also bled my cooling system, since I didn't do it after installing the new heater core. That also made a big mess. In the past when I've bled cooling systems, sometimes I'd get small splashes of fluid or a slight mist coming out of the filler neck. Not on Papa Smurf. Coolant decided to come out like a geyser when the thermostat opened. Made a lovely mess, but the process was successful in the end.

Lastly, I dropped quite a bit of money on parts to rebuild the rear brakes on the Dana 60. Parts were a little difficult to find at first, but I think I got all I need. Once all the parts arrive I will post a tutorial and "shopping list" for the Dana 60 to help out anyone else looking for parts. Doing new drums, wheel cylinders, shoes, bearings, and hardware. Also going to modify my hubs to accept the 9/16" wheel studs instead of the OEM 1/2" studs. I don't like running with 2 different sets of lugnuts on front and back.

Before the brakes get done, I want to fix the backfiring issue on Papa Smurf. Pretty sure it's being caused by the large exhaust leak from untorqued nuts at the flange. Not gonna lie, the popping when I rev the engine sounds kinda cool. The reason behind the popping is not as cool though.

Re: "Papa Smurf" - 1966 GMC 1500 Custom
 

Hm. Knocked out a rear stud and measured it. It measures 9/16" already. Knocked out a stud from the old front end, it measure 1/2". Something isn't adding up. I have good reason to believe that the front was swapped out before I bought it, but the rear looks like it hasn't been moved. Did some GMC Customs come with 9/16" wheel studs? I thought that GM didn't start using that size until 1971-1972. All the research I've done suggests that it should be 1/2".

It is entirely possible that the PO used a Dana 60 out of a different truck, or different hubs were used after it was rebuilt in Minnesota. But it is also possible that my "one year only" truck came with 9/16" studs all around, and the front end swap changed it to 1/2". I'm at a loss. This is a whole new can of worms.

I should be happy that I don't have to drill my hubs. But I don't trust some of the things that the PO did. You've seen some of the damage already. Want to see some more? At least one rear drum is missing the parking brake lever and has all wrong springs. Glad that I was already planning on replacing the whole assembly. Haven't checked the other side yet. I suspect the parking brake works on the other side though, because I can't rotate the wheels with the brake on.

Re: "Papa Smurf" - 1966 GMC 1500 Custom
 

I think I figured out the "mystery hubs". I measured and looked up the wheel studs. According to auto-part websites, the only vehicle that these studs fit is a Jeep J20 (1974-1987). I either have the hubs for a J20, or an entire axle. Hard to tell because the casting marks on the axle tube are illegible. Luckily the brake parts are the same either way.

Speaking of brake parts: I installed the last big piece of brake line today. One long piece of 1/4" line that runs from the master cylinder, behind the engine, down the frame, and to the rear axle. It was a pain in the butt to install, but it's done. 1/4" line doesn't bend nearly as smoothly as 3/16". Also, I didn't bother jacking my truck up. I opted to crawl around underneath with very little ground clearance and repeatedly hit my head on the auxiliary fuel tanks. Probably would've been easier if I had more room to work with, but hindsight is 20/20.

The last 2 pieces of brake line will get installed when I finish the brake rebuild. The rebuild will either happen late this week or early next week. I'm still waiting on a few parts. Once that is done, just need to tweak a few small things and I'll have a functioning truck.

Re: "Papa Smurf" - 1966 GMC 1500 Custom
 

Not surprising, but I hit another obstacle. I can't do the brake rebuild until I track down the parking brake levers (actuating levers). I'm missing both, and no parts supplier seems to carry them.

It's part #9 in the photo. Looks like a boomerang. Second pic is Dorman HW2553. Supposedly that kit comes with the lever, but my hopes aren't high. I ordered it and it should be here in a few days. Already ordered a similar kit from Crown Automotive. They had a picture showing the lever I needed, but the kit arrived without it.

More info: Dana 60 rear axle, 12" x 2.5" brakes.

Re: "Papa Smurf" - 1966 GMC 1500 Custom
 

you could clean up and re-use the existing one...I think I see it in the previous photos...maybe?

Re: "Papa Smurf" - 1966 GMC 1500 Custom
 

Unfortunately not. They're missing from both sides. On the bright side, the Dorman kit did come with one (right side). I'm still struggling to track down the other side. The only leads I have are that these levers were used in Chevy and GMC in the 60s and early 70s. They were used in the Jeep J20. They were also used in some Cadillac and Oldsmobile in 50s to 80s (I could be wrong on the early end of those date). So they aren't just limited in usage to trucks.

I'm monitoring my local junkyard. Hopefully one of these vehicles will pop up soon. Otherwise I might be able to take the lever I have to a metal fabrication shop. Maybe they can mirror and reproduce it.

Re: "Papa Smurf" - 1966 GMC 1500 Custom
 

Well. I found a precision sheet metal fabrication shop. They were able to reproduce the parking brake lever I needed. It took a month for them to so, but it's finally done. The shop I went to typically only serves bulk orders for businesses. The owner was very kind to make an exception for me, so long as I paid a "single item fee".

Not a single vehicle with compatible brake parts appeared in my local junkyard during the month of waiting. So the only way I can see getting these levers is to get lucky at the junkyard, buy from someone scrapping a Dana 60, or order the Dorman kit and have a shop mirror the lever for the other side.

I have to finish up a few other vehicles that I'm working on for family members. They noticed that my mechanical skills were not being used and thought it'd be a good idea to give me something to do. Once I'm finished with those, I will continue with Papa Smurf. One setback at a time, we will get him back on the road.

Re: "Papa Smurf" - 1966 GMC 1500 Custom
 

Funky, I had a copy of that ad many moons ago and I took it to the framing shop and they destroyed it. Not getting into how and become irate again, but they destroyed it. Very poor communication between the owner and the idiot who ruined it. Anyway, I am going to guess you don't want to sell yours, but would you do me a solid and post a WTB ad in the marketplace on this site showing your ad in a clear picture so we can see who else has a copy they might sell?

Re: "Papa Smurf" - 1966 GMC 1500 Custom
 

Hello GMCNUT, That is just a copy and paste saved from a thread at the 67-72 Forum or an old eBay ad I don't recall, but I don't have the actual ad.

I will post up the WTB for you.

Re: "Papa Smurf" - 1966 GMC 1500 Custom
 

It has been a while, but I'm back with another update. Working on more family cars has kept me busy. They take priority over Papa Smurf, unfortunately. Also, I bought a new-to-me GMC 1500. That one is 46 years too new to talk about on this forum, lol. Anyways, I also have an update on Papa Smurf.

I completely rebuilt both rear hubs and gutted the old drum brakes. I installed new wheel bearings and races, new seals, and new studs and lug nuts. Next logical step would be to install the new brake hardware. Just need another day of decent weather so I can do that.

Here are some part numbers if anyone needs them. I have a Dana 60 rear diff. that came out of a Jeep J20. Keep in mind that there were a few variants of the Dana 60 that these parts may not fit.

Wheel Bearing (Inner): Timken 28678
Bearing Race (Inner): Timken 28622
Bearing Race (Outer): Timken 18620
Wheel Bearing (Outer): Timken 18690
Wheel Seal: Timken 455860
Axle Shaft Flange Gasket: Fel-Pro 55350
Axle Nuts and Washer Kit: QK4763
The axle nuts require a 2-3/8" socket.
Lug Stud: 6413166 (Napa)
Lug Nut: Dorman 611161
My lug nuts and studs are 9/16". I believe every other truck had 1/2" studs.

Re: "Papa Smurf" - 1966 GMC 1500 Custom
 

Good job on the part numbers. For the other projects, you can put them in the

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. I put my woodsplitter build in there and even installing my water heater.

Re: "Papa Smurf" - 1966 GMC 1500 Custom
 

Since we're talking full floating rear axles, 25 years ago now I was fretting over getting a half or 3/4 ton truck. And I'm not sure why but almost 25 years later and 320,000 miles later it still has the factory installed bearings and seals. Guess I made the right choice all those years ago.
Never stops amazing me how these GMC trucks were built! Not many common parts with a Chevy, but I bet it's almost easier to get the GMC parts today than the Chevy parts.

Re: "Papa Smurf" - 1966 GMC 1500 Custom
 

Finally got around to assembling my rear drums. Without any detailed photos to reference, I have to assume that I followed my service manual's directions correctly. It got too cold and dark to actually adjust them, so I put the old drums back on for now. Sometimes later I'll have to finish installing brake lines to the wheel cylinders, put on the new drums, and get everything adjusted properly.

If you see something wrong in my photos, please let me know. This is my first time doing a full assembly of drum brakes. The pictures are showing the passenger side drum assembly.

Part numbers:

Rear Drums - ND 4401202 (12" x 2.5" / Lug holes are meant for 9/16" lug studs)
Self-Adjusting Hardware - Carlson H2555/H2554
Drum Hardware - Raybestos H7128
Wheel Cylinders - Centric 13462016/13462015
Brake Shoes - Raybestos 127PG (Semi-metallic pads)

And a note. The golden bracket you see in the photo is not replaceable. Earlier in this thread I mentioned how it was missing. I was able to track one down (Dorman HW2553) and then I had it copied and mirrored by a precision metal shop. It wasn't cheap to do. Don't throw them out!

Re: "Papa Smurf" - 1966 GMC 1500 Custom
 

LND, here is a link with some drum brake assembly photos.



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Re: "Papa Smurf" - 1966 GMC 1500 Custom
 

Thanks for this. Based on these photos, I have no reason to believe anything is assembled wrong. I even followed my service manual step-by-step. Shouldn't doubt myself too much.

Unfortunately, there is a problem somewhere in the braking system. Today I adjusted my drums, installed the last two pieces of brake line, and then vacuum bled everything. Ran about 2 quarts of fluid through the system. Haven't had a single air bubble all day, but the pedal has a lot of travel. It goes down about half way to the floor before it gets stiff. With the truck running, there almost isn't a brake pedal at all.

The last time I had an issue like this was on a Saturn Ion. I had just replaced the master cylinder, it experienced these symptoms, and it turned out the the new master cylinder had a bad internal seal.

Too many factors to consider on my truck. I replaced every single item you can possibly replace in the brake system. I have no way of knowing if all the parts are compatible or not. I'm relying on aftermarket manufacturers correctly labeling products.

My truck has some braking power, so I plan on taking it on a very slow road test to see if anything changes. If nothing else, the parking brake seems to work. It's super tight and I can only get 3-4 clicks out of it.

As much as my dad would hate me for doing it, I could always borrow the MC out of his 74 just to see if mine is the issue or not. I could only see the problem being either the:
1. Master cylinder
2. Proportioning valve
3. Improperly adjusted push-rod
4. Non-compatible MC bore size

On the bright side of all of this, it has enough braking power that I can probably move my truck to the driveway and get it out of the slanted gravel pit.

Sorry if the post is jumbled. I'm a bit frustrated.

Re: "Papa Smurf" - 1966 GMC 1500 Custom
 

That’s got to be very frustrating LND;
Sorry to hear that...

Here’s a link from CPP on figuring out brake issues that might help you.



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Re: "Papa Smurf" - 1966 GMC 1500 Custom
 

Vented my frustrations, read through CPPs troubleshooting sheet, and then did some research on braking systems.

Here's what I came up with:

After looking at old part numbers (**** glad I documented part #s), it appears that I ordered a MC and brake booster kit for a 1/2-ton truck. Meaning the bore of the MC is too small to push out the required volume of fluid needed for 3/4-ton disc brakes. It explains why my pedal has a good amount of resistance, but goes to the floor. The MC is currently producing pressure, but not volume.

The bore I have on my MC is likely 1" or 1-1/8". The solution is grab a MC and proportioning valve off of a 1979 GMC 3/4-ton (to match the front discs). They used a 1-1/4" bore. This will allow me to meet the volume needs of the heavy duty disc brakes.

Essentially what we're looking at is the difference between JB5, JB6 and JB7 braking systems. JB5 systems are on light duty 1/2-tons (your typical GMC 1000 or Ch*vy C10). JB6 systems are on heavy duty 1/2-ton and light duty 3/4-ton. JB7 is for light duty 1-ton and heavy duty 3/4-ton. I mixed and matched JB5, JB6 and JB7 parts. My truck has a GVWR of 7,500 which would put it in the JB7 category (7,500-8,400).

So, I'll be ordering a new master cylinder for a JB7 system and I'll see where that gets me. Probably a new proportioning valve too, just to be on the safe side.

*This post is a compilation of everything I researched today. It is accurate to the best of my knowledge.*

Re: "Papa Smurf" - 1966 GMC 1500 Custom
 

I don't like to jump the gun, but I think I solved the problem. I installed a new master cylinder. An OEM ACDelco meant for a 1979 GMC C2500 HD. Plumbed some new lines to the proportioning valve, bench bled the master, and then installed it. I also installed larger disc brake calipers because the old ones I had were meant for the light duty C25. Lots of air in my brake system, but the pedal is significantly stiffer and only sinks with some constant, heavy pressure. Quickly stomping the pedal makes it feel rock hard. I think once I get everything bled, I should have a solid brake pedal.

Really don't want to jump the gun or jinx myself, but I'm feeling good about this.
A 1/8" increase in bore size doesn't seem like much. But lets assume that the fluid is moving through a cylinder 8 inches long. A 1-1/8" bore and 8" stroke would push about 7.95 cubic inches of fluid. A 1-1/4" bore and 8" stroke would push 9.81 cubic inches of fluid. Now that's not exactly how master cylinders work, but it proves a concept. The volume adds up over distance.

Re: "Papa Smurf" - 1966 GMC 1500 Custom
 

Are the brake lines copper plated? From what I been told solid copper brake lines is a no-no and prone to failure. Correct me if I'm wrong.

Re: "Papa Smurf" - 1966 GMC 1500 Custom
 

They are the NiCopp brake lines. An alloy of primarily nickel and copper, as well as some manganese and iron. They were recommended to my by someone who makes custom brake lines for a living. They have the strength of steel lines, but they bend smooth as butter.

Sent from my SM-G970U using Tapatalk

Re: "Papa Smurf" - 1966 GMC 1500 Custom
 

Finally got my truck to the driveway. The brakes work great! They're actually too good. When I pushed the clutch in, the truck would slowly stop before I touched the brakes. Couldn't get it started in second gear, had to use the granny gear to get it rolling. It also didn't roll back when it was on the sloped part of my driveway. I probably adjusted my pushrod in too far, or I need to back off my drums a bit. I'm just glad I have solid brakes all around. Next task is to obviously adjust my brakes so they don't drag, check and change all the fluids, and then get this thing sent off for an alignment and new tires.

What honestly surprises me is that, after two years of sitting, there wasn't a single wet spot in the gravel. That either means I have no leaks, or the fluids that might be leaking are completely empty. "If she ain't leaking oil, then she's out of oil."

Re: "Papa Smurf" - 1966 GMC 1500 Custom
 

Small update. Brakes are still locked up because I've been busy with other vehicles. You can see those in the other build thread. That thread is not yet up to date though...because I've been busy.

Today though, I decided to retackle my leaky radiator. Original solder joint did not hold so I tried again. After 4 failed attempts, I finally got it sealed up. I've never done any plumbing soldering, only electrical soldering. It seems that the trick with plumbing solder is to clean everything with muriatic acid, heat the area, clean it more, then add flux, heat, flux, heat, flux, heat, solder. Follow those steps and you should get a clean solder joint. I'm not too happy with how globby it looks, but it seals and is adhered to the radiator, and that's what counts. I might cover it with some JB weld and then sand it smooth. Kinda like bondo.

I should have some spare time this weekend to get the timing sorted on my engine. Needed the radiator sealed so it didn't spray hot coolant on me while I was working. The timing seems way off. Hard start when it's cold, runs okay hot but it seems like it's running rich.

Also I noticed that all of the fittings on my 1/4" brake line are weeping brake fluid. Not leaking, just weeping. The master cylinder is not missing any noticeable amount of fluid, but all of the fittings are wet and some of them formed droplets. I probably need to go through and loosen each fitting then tighten it back down again. Repeat 4 or 5 times to form the flare to the flare nut. All of my 3/16" flares are fine, so I'm guessing it's just an issue of the flares not being formed properly. Again, it's not a bad leak. The reservoir is still full and no drops have hit the ground.

Re: "Papa Smurf" - 1966 GMC 1500 Custom
 

Been neglecting this forum. A few months ago I got my engine close to perfect on the timing. It doesn't spit flames and backfire anymore, but it still could use a bit of tuning on the vacuum advance.

I also solved my locked up brakes. First, the parking brake was adjusted too tight by the previous owner. Loosened the cable, pulled the handle 4 clicks, then tightened the cable until the brakes started to drag. After that, I had an issue with a kinked brake line at the proportioning valve. Used my last 6" of brake line to recreate the 4" section; no room for error. After that was solved, I had some preload on the master cylinder. Seeing as my pushrod is already as short as it can go, I had to put 2 washers behind the master cylinder. It solved the issue. Wheels spin freely with engine running and engine off, but the brake pedal doesnt have too much travel before the brakes are applied.

This truck is almost road worthy. It still needs tires and the control arm bushings torqued, but I think I can solve those fairly easily. I got a new torque wrench that should help me get the leverage to get 220lb-ft on the upper bushings. Also, I recently got a job at a tire shop. Might be able to bring the loose wheels to work some day and mount up some new tires on my lunch break.

Re: "Papa Smurf" - 1966 GMC 1500 Custom
 

Tried to finalize the timing on my engine today. Things were going well until my alternator died. Shortly after that happened, my distributor cap decided to snap off. Oh, and I had to stop a few times to let my engine cool down because it was running at 240 according to my thermal gun.

My truck is dead, but it presents at least two opportunities for upgrades. I'm going to install an HEI distributor and an internally regulated alternator. Additionally, while I have the distributor out of the way I will also install an electric oil pressure sensor. I'm hopeful that sorting out the timing will also help the engine run cooler.

Sucks to take 2 steps forward and 3 steps back, but it'll be good to get this engine running smooth and clean.

I know there is some speculation on whether HEI distributors will fit on a 350 in our trucks, the main concern being firewall clearance. From what I've seen it'll be a tight fit but it will indeed work. I'll let you know otherwise.

Tomorrow I'm making a trip to the parts store. Hopefully I can get my truck back up and running before I have to return to work next week.

Re: "Papa Smurf" - 1966 GMC 1500 Custom
 

New alternator is installed, HEI distributor fits, and my electric oil pressure sensor just barely fits. Tomorrow I plan on actually wiring these all up. I also installed new spark plugs gapped at .045 for the new HEI distributor. I'll be replacing spark plugs wires as well.

When I pulled my wiring harness today I saw the horrors of 50+ years of custom wiring. The harness is a complete mess. After trimming most of the terminated wires I think I can finally makes sense of what the harness was meant to do.

Once I get everything back together I'll let you all know about part numbers and wiring diagrams.

On an interesting note, whoever installed the last distributor forgot the gasket. So I solved one major oil leak there. They also did not use any sort of sealant on the mechanical oil gauge, so that is a second leak solved (assuming I used enough of the proper sealant). At least I know for certain this gauge won't leak inside the cab. Lol.

Re: "Papa Smurf" - 1966 GMC 1500 Custom
 

My truck did a very good toaster impression today. Lots of smoke coming out of the air vents.

Long story short, something in the original harness was shorted and melted almost every electrical wire inside the cab. And it only took a few seconds. I saw smoke, I unhooked the battery, everything was burnt and melted.

All the wiring I did is fine. It isn't melted, it didnt even get warm. The only thing I did with wiring was remove/replace the resistor wire, remove the alternator external regulator, and repair wires that were spliced for accessories that no longer exist in my truck. Everything is wired up according to my 65-66 GMC FSM.

I don't even know if my truck runs with the new distributor because I never got the chance to crank it over.

Re: "Papa Smurf" - 1966 GMC 1500 Custom
 

Man, just read through your entire thread, ungrateful work it seems like. Fixing the crap produced by the previous owners take a heck of a lot of work. Will be following your thread with interest and I commend you on your ability to just carry on (when you aren't out fixing family vehicles!)

Good luck.

David (also a young guy at 22)

Re: "Papa Smurf" - 1966 GMC 1500 Custom
 

It's only a matter of time before the grandkids grow up and buy their own project vehicle! Lol. And honestly, in a 50+ year old truck, some of this should have been expected. This truck has been someone's beater-with-a-heater for a long time. Only makes sense that several "goodnuff" fixes have been made.

I've been slowly working on Papa Smurf. Winter and work has made progress extremely slow, but here is where I'm at:

I bought a Painless Wiring kit (PN #10112). I've already removed most of the wiring from my truck. I just need to remove the headlight and taillight harnesses. Everything is getting carefully removed and labelled because some parts of the original harness may need to be reused. Obviously the melted parts can't be reused. That would be my ignition connector and passenger side bulkhead connector.

While working on wiring, I decided that now was the best time to solve my overheating issue. I'm going to be removing the current cooling fan and replacing it with some electric fans. I nabbed some cheap fans from a C5 Corvette, a BMW 325I dual temperature switch and wiring harness (91c/99c), a dual fan two speed LS relay kit, a new thermostat housing with a 1/2" port for temperature switches, and a 185F thermostat. All of this will be cobbled together to improve cooling. In theory, my thermostat should open at 185F, my cooling fans should kick on low speed at 195F, and high speed at 210F.

In addition to all of the cooling fan supplies, I had to upgrade my alternator again. The 70 amp alternator wasn't going to be sufficient for the fans. On startup, both fans can draw up to 60A (30A each). Once they are up to speed, that draw will decrease to 30A or less (about 15A each). That is still a significant portion of my current alternators charging capacity. To prevent any issues, I went with a 140A alternator. That will provide more than enough capacity for the fans, and any other accessories I decide to install later such as AC or a new radio.

So far all I have done is test fit the fans. They fit almost as if they were made for this truck. I bought them because the fan measurements were very close to the radiator dimensions. I also found that fans from a Saturn Vue are rather close, but the C5 is even closer. All of the cooling fan supplies cost me about $500. Honestly not bad.

Hoping for some warmer weather soon so I can actually start installation of everything.

Re: "Papa Smurf" - 1966 GMC 1500 Custom
 

That's a big ol' alternator! Probably robs a lot of hp as well... :teehee:

Kind of wondering why it overheats? My 305 never goes above thermostat temperature. Is the radiator plugged?

Re: "Papa Smurf" - 1966 GMC 1500 Custom
 

Radiator isn't plugged to my knowledge. I believe the overheating issue is due to lack of airflow through the radiator. My truck has a SBC 350 in it. The SBC is way smaller than the 305 V6 so it sits further back in the engine bay. The PO put a fan spacer in, but the fan still sits pretty far away from the radiator. There is no shroud to help direct airflow, and there is a giant gap in the engine bay.

Basically, the cooling fan wasn't doing much besides stirring up dust. The truck did cool down a bit if I drove it, but not by much.

Re: "Papa Smurf" - 1966 GMC 1500 Custom
 

Progress update. Fans, alternator, and cooling neck/sensor have been installed. Wiring is going in and I am also upgrading the headlights, marker lights, tail lights, and reverse lights.

Installing the fans was super simple. I just used some aluminum L brackets that I had lying around. Drilled some holes in the radiator shroud and the fan shroud, then bolted them in. The HVAC tape is to seal the gaps. I want the fans to pull air through the radiator, not around it. The fans and coolant sensor have all been wired in to the relay kit. All that is left to do is to hook it up to the Painless wiring harness.

Speaking of wiring, the mess of wires that you see is surprisingly organized. Painless does a great job of labeling and binding everything together. Right now I'm working on getting the wires routed the way I want. Then I will wrap them in split tube and secure them before I start making connections. I am also working on a few upgrades to lighting first.

The headlights I'm installing are the Colorshift lights from Oracle. You can see the difference between stock lights and the Oracle lights. There is an LED ring around the edge that I can control with my phone. I can make it almost any color/pattern that I want. Should help my truck stand out even more. In addition to that, the bulbs are being upgraded to LED. They still use the same H4 connectors though. The only mods needed to make these headlights fit are some mods to the buckets. Little bit of cutting and drilling (as shown in the last photo). So far I have two buckets done. They're taking me about an hour a piece. I'm trying to go slow so I don't ruin them entirely. In the even that I do mess up, a lot of these parts are available aftermarket. Even the headlight adjusters are easy to get (most of mine are broken. 56 year old plastic is very easy to break).

Besides that, I have some sequential LED tail lights. No mods needed for that. It plugs right into the original harness. Same with my LED reverse lights.

Lastly, I am installing clear lenses on my marker lights. The bulbs are being replaced with LED switchbacks. If you don't know, a switchback bulb is solid white when the power is constant. When power is "pulsed" (when a blinker is turned on) the bulb will change to orange and will flash. My marker lights will function as both an amber blinker, and a white DRL. No mods needed for this except a no-load flasher and the switchback bulb.

Lots of things going on. I cannot wait to get all of this installed. Hopefully the junkyard fans actually work. I didn't think to test them before installing them.

Re: "Papa Smurf" - 1966 GMC 1500 Custom
 

I've been hard at work getting all the wiring put together. So far I have everything except my interior and my taillights wired up and ready to go. I even got my truck started today. I never got to hear it run when I installed the HEI last July because it caught fire before it ever cranked. Thankfully, the only smoke and fire that occurred today was from the backfiring in my carb (last time I installed the distributor, I put it in 180 out...woops). I couldn't let my truck run for long though. My brand new thermostat housing is cracked and leaking.

As far as wiring goes, the Painless kit really is simple to install. I swapped around a few wires to suit my needs then slapped it in some split tubing and ran it where it needed to go. After that it all fell into place. Keep in mind that the kit is made for Ch*vy and GMC. So some wires are missing, and some aren't used. Keep your original harness as reference and be ready to reuse/rebuild some parts of the original harness. Just as an example, I have to rebuild my heater and blower motor harness to reuse. I also have to splice my original gauge cluster harness into the Painless harness.

No pictures this time around. I don't really have anything interesting to show. Just wires and such. If you decide to do the Painless rewire and have questions, feel free to ask.

Last thing. I'm looking at replacing my coolant reservoir. Did our trucks even come with an overflow tank? My service manual mentions them but I don't recall that it showed what they looked like or where they were mounted under the hood.

Re: "Papa Smurf" - 1966 GMC 1500 Custom
 

Things are coming together nicely. My cooling fans work beautifully. They keep my truck running with the needle right in the center of the gauge. On cooler nights they only stay on for a minute or two. Hotter days, they sit on low speed at idle for a long time. But they haven't kicked on to high speed so I know they're at least maintaining temperature. I also solved my coolant reservoir issue. Summit had on that was fairly easy to install. Should serve the purpose nicely.

My headlights works. The LED bulbs are super bright. I have to aim them still, but that'll be easy. The LED halos also work. They were a bit tedious to wire up. Each halo has 4 wires that needed to be connected with butt connectors to the Bluetooth module. 16 butt connectors later, everything works.

My taillights and reverse lights are installed. I need a new reverse switch for the lights to work, but my taillights work. The sequential blinker and brakes look awesome.

My front blinkers also work, but I need to figure out how to attach the new lenses to the housings. The lenses I bought came with rivets that were way too big to fit. I found some screws that fit tight, but they stick out too far in the back and hit the hood when I try to install the housing.

And lastly, I've actually started driving my truck regularly. I got it tuned perfectly. It starts on the first turn of the key and is ready to roll after less than a minute of warming up. It's not registered or insured yet so I have to keep it off the main highway, but it handles nice while cruising around the neighborhood. I even had a chance to do some light towing with it. Had to pull my 1938 Buick out of the backyard. I hardly felt it. My truck powered right through it.

All in all, I'm starting to see 3 years of hard work paying off. I only need the front blinkers installed to make my truck legal. Then I can invest in new tires and an alignment. I'm excited for the future of this project once it's on the road.

Re: "Papa Smurf" - 1966 GMC 1500 Custom
 

I have good news, bad news, and in between news.

I've managed to torque my control arm bushings, only 3 years after installing the arms. Had to unbolt my exhaust from the manifolds and remove the front shock absorbers. Turn the tires as needed and use a 4 foot long torque wrench. Easy peasy.

I also fully installed the coolant reservoir, and got a new washer reservoir that I believe to be period correct. On top of that, I replaced my wiper motor, washer pump, wiper switch, and headlight switch. All of that works perfectly (minus the washer pump that I haven't tested yet). My marker light housings were installed. I ended up using the screws and grinding them down until the housings fit in the hood. The clear lenses are much cleaner looking, in my opinion. I also aimed my headlights and got my reverse lights wired up.

As for the bad news...since it got cold I decided to adjust my choke. I got it set and wanted to warm up my truck. I was off doing other things while it was idling when I suddenly heard liquid hitting the ground rapidly. Sure enough, my radiator gave out. The truck didn't overheat, but it appears that the underside of the top tank is where the leak is at. It is going to need a recore before I can continue. I have a local radiator shop that should be able to do it. If not, I'm sure I can get a C5 radiator to fit. The cooling fans would certainly work.

That's where I'm at. Just tying up loose ends while saving money for tires. The radiator is a setback, but not the end of the world. Happy Thanksgiving!

Re: "Papa Smurf" - 1966 GMC 1500 Custom
 

Update on my radiator. I took it to A1 Radiator here in Reno. They told me that the core that was currently in it is not correct, meaning that someone has rebuilt this rad at some point before. He also told me that it would be about $750 to restore it to factory original. He gave me a few other cheaper options, such as using a 2 core vs a 3 core.

I went with the OE style core. Everything should be done by the end of the week. They are going to fix dents and cracks in my tanks. He also noted that, with the proper core, my radiator will shrink by about 1/2" on the sides. That shouldn't cause any issues with my electric fans.

I wish I took some detailed photos of what it looked like before. Regardless, I'm excited to see what it will look like once restored.

Additionally, I ordered a radiator from the EvilBay. Less than $100 for a used C5 rad. I'm going to see if I can adapt that to fit, just in case my Harrison rad is too nice and pretty to be used.

Re: "Papa Smurf" - 1966 GMC 1500 Custom
 

I present to you: a restored Harrison radiator. They fixed the dent in the inlet pipe, resoldered the crack in the tank from the inside and outside, put blocks on the sides to hold the fins in place, resoldered every connection, and gave everything a nice coat of black paint.

I'm happy with how it turned out. It was expensive, but worth every penny. I'll give an update on how it performs once I get a chance to reinstall it.

As for the C5 rad. I haven't had a chance to test fit it. I can already tell it's probably going to be too wide and not tall enough. I'll play with it later.

Re: "Papa Smurf" - 1966 GMC 1500 Custom
 

Words cannot describe how excited I am. I know it has been a while since my last update, so sit tight.

First. The restored radiator is great. Cools the truck quickly. I took my truck on a long cruise around the neighborhood and the temperature never went past the middle point on the gauge. Fans stayed on low speed for most of the drive, but it was almost 100 degrees out so that is expected.

Second. I tried installing a washer pump. The original mechanical pump. I bought one from Cardone (Car-don't) and it didn't function properly. I'll try again later.

I also tried fumbling with my motor mounts. I tried to flip them because I thought they were backwards. It turns out that the perches are just wrong. From my limited research it seems that there are differences in perches between C10s and C20s, and even different years. I'll need to get them fixed because my motor vibrates a fair bit with only have the spring perch being bolted down.

And finally for the exciting news. Tomorrow (8-7-2023) I will be putting on tires and performing an alignment on my truck. My boss made sure the alignment rack was free for a few hours so I should have plenty of time to dial in my specs. My truck is insured and I have made an appointment with the DMV to register it. It isn't perfect by any means, but it is legally roadworthy.

After 4 long years I will finally be able to enjoy my new truck!