My Scout friends came back on Sunday to help me button up the rear drum brakes on Peer Pressure. When last we left off, we’d put new pads and hoses on the front discs but when we pressurized the system one of the rear cylinders blew out under the increased pressure from the hydro-boost. It was getting late, and everyone was tired, so we agreed to meet again to finish it up. In the week following I bought a new set of drums to match the shoes I got with the Scout, as well as a full spring kit and two adjustable valves.
Bennett and Dennis came by in the early afternoon, bundled up for the freakishly cold weather (the day before, it had been sunny in the high 80’s) and we set to work. First we jacked up the rear and put the axle on jack stands. Then we pulled both wheels. I told Dennis I’d never done drums before, only discs, so he sat with me on one side while Bennett had the other side to himself. We pounded and pried off the drum on the driver’s side, mangling one of the clips in the process, and tore down the drum.
Dennis stepped me through the rebuild process patiently until we got to the clip that had been mangled, and then I had to get on the phone to find a new one. Luckily a local parts store had the kit we needed in stock, so we ran out to grab it.
I had inherited a set of brake shoes when I bought the truck, so it was a bit of a toss-up whether they would fit in the drums I got from NAPA. It turned out I needn’t have worried, and they went in without a hitch. Somehow Bennett got his side’s clips, springs, notches and pins aligned correctly and installed before Dennis and I did.
The shoes on the truck were still in excellent shape (as were the drums, actually) but we replaced everything while we had it open. Bennett had to reflare both brake lines because the fittings had rusted to the cylinder, which took time. Then we bled the whole system out, reflared a leaky fitting, and bled it again. At that point everything was holding pressure so Dennis fixed the brake light switch and we opened the barn doors for a test ride.
The difference is immediate and dramatic. The pedal throw is similar but the brakes dig in and hold a lot faster than they ever did before; the whole truck comes to a stop much faster and with purpose while the old system took a lot of frantic stomping and swearing to work. It’s going to take some getting used to, but that’s the kind of progress I like. It’s great to finally have this project completed.
I’m continually amazed and humbled at the generosity and patience of my friends, and I am thankful for their time and expertise. And they’re a lot of fun to hang out with. I really don’t know how I would pursue this hobby without them.
Last night’s cold and gusty weather continued into today, freshly piled leaves cluttering up all the places I’d raked in the rain last weekend. I had guests coming to the ghetto garage, so I tried to church it up as much as possible. Ray arrived from PA early, and stopped to pick up coffee and donuts for me. Bennett arrived soon after, and then Brian, Dennis, Brian H, Carl, and Alan. We stood around and shot the shit for a little while, and then dove into our list.
The Hydroboost unit went in with little fuss, although I can’t take any credit because I wasn’t doing much of the work. Bennett, Ray and Dennis are the subject matter experts, so the rest of us sort of stood around in my crowded little garage and watched as they worked their magic. Bennett pulled the battery, removed the stock brake booster and cleared the lines.
Ray set up the aluminum standoff block and drilled new holes in the Astro mounting plate while Dennis pulled the assembly under the dash apart. Within an hour the main unit was bolted in place and the hoses were run. There was some concern over the hard lines going from the pump to proportioning valve but Bennett showed his skill with a flare tool and had new ones bent and fitted in an hour.
While we had the brake system pulled apart, it made sense to pull the wheels and go through the brakes. However, NAPA failed me on Thursday and did not put my order through for pickup on Friday, so the pads, calipers, cylinders and other parts I’d ordered never arrived. Bennett raided his considerable parts stash and brought a new set of front pads, but when we pulled the front wheels off and looked at the calipers (and banged on them with a hammer) it was clear we would need replacements. I started working the phone, and a different NAPA came through for us. Somewhat stalled, we took a break for lunch at the local diner, and by the time we were done the parts were waiting for us.
Back in the garage the new calipers went on smoothly, and we bled the brake system from the front to the back. A few adjustments to the pedal were made, a legacy vacuum hose to the old booster was plugged, power steering fluid was procured and added, and the truck was idling smoothly with no squealing from the pump. However, Brian noticed the rear passenger brake started leaking heavily, so we shut the truck back down again. Apparently the brake cylinder blew up with the increase in pressure from the pump.
It was 6PM, getting cold, and already dark, so we called it a day at that point. I’ve got a list of parts to buy for the rear brakes–mainly a spring refit kit and two new soft brake lines, because I have shoes and bought cylinders today. We’ll pick up part two in a couple of weeks.
I got a really nice letter from Bennett, one of my local Scout friends, when I was laid up last month. He offered to get our local group of IH guys together and get some work done on Peer Pressure while I was laid up, the generosity of which blew me away. We set up a date in early March and he had me put together a list of stuff I’d like to tackle: Hydroboost, fuel sender, and maybe something else if we have the time.
The Hydroboost project involves removing the big stock brake booster and replacing it with a GM hydraulic unit sourced from an Astro van and hooking it into the power steering pump. What this does is improve overall braking power, allow for added stopping power in the event of an engine shutoff, and make more room in the engine bay. Back in 2013 I assembled all of the parts but stalled out, because I don’t trust myself enough to follow the sparse instructions found online or bleed the brake system correctly by myself.
Clockwise, from upper left: Astro brake unit, power steering hoses, power steering adaptors, aluminum standoff block, brass fittings.
So I’m sending this photo over to Bennett and Ray, the acknowledged experts, to make sure I’ve got everything I need. I’ve got to pick up new brake fluid for sure, but hopefully everything else is correct.
So all three main sections of Good Carb are washed and drying on the bench. I dunked them each in Simple Green for a couple of days and then scrubbed them with a toothbrush, and 99% of the crud came right off. After a rinse with warm water, they look close to brand new. I’m going to let them dry completely and then start tearing down and replacing parts next week.
I reassembled the stunt carburetor I’ve had sitting on the bench since the end of January and put it aside so that I could tear down the good one. Actually, Jen needed the box that the rebuild kit came in for something, so I figured I’d straighten up the bench while I was moving the parts around. Once I’d gotten that put back together, I looked over the good one and started pulling it apart. I was pleased to find it’s in really clean condition, with a little dust in the phenolic bowl, a tiny bit of corrosion around the air horns, and a lot of clean metal everywhere else. The floats are almost brand new (but will be replaced with brass) and the internals are all clean as a whistle. There was a little leftover gas trapped in the horn that made the basement smell, so I moved it out to the garage this morning, where it’ll get a good dunking in carb cleaner.
When I was a kid, I spent countless hours of my life building with LEGOs on the floor of the family room. I’d build something, take it halfway apart, put it back together again, and then repeat that cycle until I got it just the way I wanted it. All of this was unwitting practice for my adult life, where I’ve disassembled computers, electronics, power tools, engine parts, and other assorted machines without fear of being unable to re-assemble them.
So, working my way through the videos I’ve downloaded, I decided I’d start disassembling the dirty unit first to get my practice in.
Most of the linkage came off relatively easily, and when I understood the secret Thermoquad disassembly trick (two hidden screws under the primary butterfly) the whole thing came apart pretty easily. It was then when I understood why it was so filthy. At some point it had gotten a lungful of water or mud, because both chambers were full of brown crud. The underside of the resin bowl was filled with corrosion and blackened carbon. I began to get nervous, thinking I’d never get it cleaned up.
Into a bucket of concentrated Simple Green it went, and after about an hour’s soak the resin bowl came out looking brand new. I scrubbed it with a toothbrush and bottle cleaner to get the residue out, and let it dry on the bench.
Then I threw the top air horn in to let that soak. Corrosion had crusted over everything made of ferrous metal; the float arms were rusted solid. The whole thing looked charred and sooty. I figured I’d try the detergent to see how clean it would get first.
After about two hours I was shocked to find it had turned Simple Green to Simple Brown, and most of the soot had disappeared. The aluminum appeared much cleaner, and the metal parts were more visible.
It’s still pretty fucked up, though; Simple Brown can’t dissolve whatever that white crusty stuff is in the upper left, and the well under the float (that black square thing on the left) is filled with it. It’s going to soak overnight, and then if I can’t get the parts free I’ll put on some gloves, take it outside, and hit it with the carb cleaner.
Santa (technically, my sister’s boyfriend) brought me a lovely gift this Christmas: a carb rebuild kit for my spare Thermoquad including all of the gasketry, springs, and other small parts needed to overhaul the mechanical bits. Introduced by Chrysler in 1969, the Thermoquad is a four-barrel carburetor designed with two small primary and two large secondary bores. At idle or cruise, the primary bores supply fuel to the engine in small amounts for efficiency, and under load or acceleration the secondary bores open up to dump fuel into the engine, adding power. It’s built around a phenolic resin chamber sandwiched with two aluminum plates, which was supposed to keep the temperature of the upper bowl 20˚ lower than standard metal carburetors of its day–because vapor lock was standard equipment on a 440 big block. So I’m going to have to study up on this Malaise-era marvel of engineering.
My engine, near as I can figure, is a 1979. As the 70’s wore on and emissions standards got stricter, engine displacement decreased and smog equipment strangled engines. IH trucks weren’t as strictly governed as passenger vehicles of the era (trucks over a certain weight and load limit were exempt from CAFE regulations, hence IHC advertising the Scout as the XLC in 1975 onwards) but smog equipment was still added to pass emissions tests, and the carbs got more complicated as the decade drew to a close. The Thermoquad sprouted all sorts of ports and valves and complicated linkages to govern choke, temperature, airflow and throttle, and the result is a lump of metal that looks like C-3PO screwed a pinball machine.
I’ve got three Thermoquads in my collection. The first is the one that came on Peer Pressure, which I had overhauled by my friend Rodney a few months after I got the truck. Tracing the serial number (9128S), it was originally made for a ’79 IHC 345ci engine with an automatic transmission. Rodney is a gearhead of the first order (he has a slingshot dragster parked in his driveway) and no stranger to carburetors. He made it sing, but that was eight years ago.
The second is a spare I picked up from a fellow north of Baltimore. This too is a 9128S. It’s the spitting image of the one on Peer Pressure, minus the funky extra linkage on the throttle arm to the left. It’s also the rebuild candidate and the one I’ll be working with here.
The third is a spare I picked up from my friend Jason, who converted his Traveler over to fuel injection two years ago. Tracing the serial number (9203S), it was originally made for a ’79-80 IHC 345ci California smogged engine with an automatic transmission. The top of the air horn at the fuel inlet is different, and there is one vent tube where my other carbs have two. It’s also super crispy and in need of a major wash. It will be my bench reference and possibly a source of spare parts.
The first order of business is to arm myself with knowledge. I downloaded a series of getting-to-know-you videos from YouTube where a gentleman steps through the features of the TQ, and another where he goes through the steps of rebuilding one. I’ve got the original ’72 Chrysler TQ service manual, an updated ’82 Federal Mogul manual, and the Dave Emanuel bible.
The first order of business is to clean them both, which will require a bucket of Simple Green and a couple cans of carb cleaner, which I’ll pick up this weekend. Then it’s on to the teardown.
Wow, it’s been several months since I’ve updated here. There really hasn’t been much to add; Peer Pressure has been running reliably and well all summer and I haven’t had a whole lot of time to make any upgrades or do any serious work. About all I’ve done is add a bicycle quick release to the underside of the rear seat. I broke down last weekend and put the hardtop on, which was hard because it was 80˚ on both days. Today was 60˚, and there’s nothing more uncomfortable than wrestling a 300-lb. pile of metal in the middle of November.
I am looking at one of the Champion aluminum radiators to replace the original one I’ve got; the outlet on the filler neck to the overflow tank came to me disconnected where the copper had been brazed. Mr. Scout has one in Chewbacca and says it works great. I may also buy a rebuild kit for my spare Thermoquad and tackle that inside over the winter months. (I’ve been saying that for three years now…)
I really don’t have much to update here. Peer Pressure has been getting regular exercise each weekend and running like a champ, if not a little rich. I had 20 free minutes last weekend and was able to get a bunch of vise grips on the seat belt bolts in the bed so that I could loosen and spin them 180˚ so that they’d be easier for Finn to grab. I did loosen the bolts on the Tuffy console to shift it forward but it didn’t budge. The bolts are long enough that there’s no adjustment possible, so I’m going to need to drill three new holes in the bottom of the console to get it to move. This will allow for the rear seat to fold and tumble easily.
I took Sunday afternoon to pull the old solid windows out of the traveltop and look at the frames; with the exception of the bottom of the driver’s side lip, it all looked to be in great shape. I sprayed rust converter on everything I saw, let it dry, and then sprayed it with paint before putting the sliders back in.
I couldn’t figure out how to get the new rubber Mike sent me to work, so for now I reused the rubber they came with, and it went in easily.