Geoff Weeks

I could be mistaken, I always understood the 'U" was for Urban, a short nosed tractor to maneuver in tight places like East coast cities. Much like the IHC Fleetstar. 2 cyl under the hood, 2 under the dash and 2 beside the driver!

tire | FMCSA (dot.gov) Here it is in print

Re gooved tires are prohibited, re capped are not. Re-cap are prohibited on passenger (bus) steer. It is in the federal (Green book) register. Smaller truck tires (lighter) up to a certain ply rating/ weight limit may be re-grooved, it the tire says "regooveable" . I went through the same CVSA course the truck-cops did, a few were in my class. That was in the book.

Long time ago on a different forum, someone was looking to mount a rack and pinion gear on an axle, he was told it was illegal to mount it there (not by me) and I took the man's word that it was not kosher to do so, as I had never seen it done in any road vehicle. It adds a lot of Monkey motion to the steering shaft, with the axle going up and down on the suspension and also moves it down lower to the road where it could get smacked. For those reasons I never questioned the "illegal" statement that was made, I should have because of the t nonsense I have heard as "illegal" in my time. Everything I worked on (Macks included) had the steering box on the frame. Too many spout the "Illegal" claim but can't back it up. Like recaps on the steer of a truck, no, it is not illegal. It isn't often done, but it isn't illegal. My bad, for not researching it.

Well, that is something I have not seen before, so I learned something new! I can see a whole bunch of reasons why it never was popular, but I believe you it was done.

Not so far out. I have heard and read about, heat exchangers and even running the pump water through the engine to keep it cool on long fires. If that truck at one time had some sort of heat exchanger, someone may have fitted a filler cap (neck) on an old hose connection when that equipment was removed.

My Fleetstar's of that vintage have S cam rear and wedge front. With it pulling badly on brake application, it could be an S cam out of adjustment by a lot, or it could be a frozen wedge, which happens more often. That isn't a low air switch in the lower line, it is a hyd brake light switch! I know it is new and you want to drive it, but please have someone who knows a bit about trucks come by and give you a hand. You get stopped on the road, and the result is likely a tow bill and a ticket. A single rear with no spring brakes and a 2 speed axle (or had one at one time)? So must have a driveshaft E brake? I worked on a school bus that was set up that way (air brakes but only driveshaft E brake), but that would be fairly rare. Most air braked trucks are required to have spring brakes, I thought the school bus was an exception (didn't want a school bus stuck on RR tracks because of an air problem). Early stuff, yeah they had air brakes and either drum or disk driveshaft brakes. I know most had to have spring brakes starting back in the 50's or 60's. You listed your location as USA, which isn't helpful, if you were near me, I'd drop by and at least get you started on what needs to be done. As it stands I have no idea what part of the country you are in.

I know nothing about the truck model in question, but have NEVER seen a steering box mounted to the axle on any heavy truck. So I can't see that being safe or legal around here.

Radiators & Cooling Systems: Truck, Semi, Heavy Equipment, RV | RSH – Radiator Supply House

I don't think they mfg radiators. L&M Radiator Hibbing, MN Mesabi.com

If the truck is "down" without a new radiator, it seam to me that the "where to get a core to rebuild" should be moot. Northern Detroit rad come to mind, there were others that catered to the O/P? You want someone who will not buy a pre-made core and just bolt or solder the end caps on, you want someone who can do the whole job. It may cost a fair bit in shipping, but that is what it is. I am trying to remember the big names in radiators for trucks, but my memory isn't what it used to be. When I found the shop I used, I never tried to do the job myself again. They weren't quick or cheap, but were good and stood behind their work. I heard they closed a few years ago. Worse case you could look into the mfg that supply construction/ off road equipment, but their prices aren't going to be as cheap as automotive.

My shop has since closed, but they would have "custom made" cores made for my trucks. Yeah several years ago (may be 10) I spent $2150 on a radiator and $1800 on the out of frame rebuild kit! Yep, more in the radiator than the engine. Truck wouldn't be useful without both being done. Nothing like pulling the Big Horn mts, wide open fully loaded 45 min @ 25 mph and not having to worry about the engine or radiator. My shop would take the tanks off, cut the tubes at the end-plate and send it out with the width needed, the core would come back and they would assemble. Also allowed for more tubes (with new end plates) or other changes. All it takes is money!😁

The Zenith I'm working on now is nice in the throttle shaft, the accelerator pump check and discharge nozzle were shot/plugged and that will cause some running issues! The Carter BBR next up will require a shaft bushing and may be some build up on the shaft and re machining back to std size. Back at the time I was wrench turning in a automotive shop, I would take a "junkyard" carb over a "rebuild" from some of the major commercial rebuilders. I've seen some real junk. I had one where I could get a brand new throttle body, but for most I would get one from a yard and overhaul it. Any extra time spent setting up the overbore on the throttle body will pay dividends, just like any machining operation, sloppy set up ruins a good machine job.

Bushing are no problem internet search show all sizes with reamers included. Trick is being careful on the set up so you keep the shaft centered where it was to begin with. Get the alignment wrong and the throttles will not close properly, or the ports will be in the wrong area to function properly.

My BBR is going to need throttle shaft work if I am going to reuse it., might get another Zenith on it until I get around to machining the throttle shaft bore and sleeving it.

Hey Jo-Jo does your K-7 have a Zenith, Carter or Holley? I'm going through mine now and got the IHC "Shop talks" on the Zenith and Carter as they show the breakdown of the carb and sequence better than the shop manual. Also list the factory tools, but finding a set might be hard. Shop talks are IHC's training manuals that go into more depth, kind of like what you get at a factory school today. Anyway, I could try and scan them if you want one. I think at least one of my Carter's is going to need a sleeve in the throttle shaft bore.

Yeah, those can be fixed but not with just a gasket kit. I'm looking at an old Zenith and may be a Carter that need that fixed.

Two common reasons you see long studs: 1 is for a non metallic spacer to isolate the carb from the cast iron manifold to prevent heat from the engine transfering to the carb, the other is when a flow governor is used between the carb and intake. Since yours has the Holley Centro-vac gov, heat transfer is the likely reason. should run a lot better with the non-metered air kept out!

I don't know when you tried, but when I needed a rugged phone I found a flip phone that was rugged and could be ordered with or without a camera for secure locations. Most at Verizon had never heard of the model, said it didn't exist, but I pushed until I found someone who did know and get what I wanted. They want to sell what they stock, not what you want.

picky linky no worky

I'd rather be a seppo that septic anyway!

Nope, we're "septic's" in Aussi slang. I guess it depends on how polite they want to be.

Yep, same with Interstate McBee, have to go through a dealer. Kind of a pain, but I understand it. Once you find someone local you can use or a good internet supplier, it is almost like having an account. I had a good Internet one that turned bad, so I can't recommend them, Toward the end I was using Vandehaag's for S&S (Newstar) and Interstate McBee. I could call up with the part number and they would order without a deposit or having to go to them.

If you have checked for a vacuum leak (unmetered air entering after the carb). take a good look at the distributor. Any play in the shaft can cause the dwell to go haywire when the advance starts to pull in. I'd 1st check the carb and intake for reason why it seams to be lean. But if you find nothing wrong look at the ign side of things. I had a 392 in a school bus that was in a shop for a valve job. Wouldn't run for crap and the shop wanted to put a new carb on, I wouldn't authorize it as I knew the carb was fine. They put one on to "show me" and it didn't run any better, had egg on their face and had to re-install the old carb and eat the price of the new one. Put a dwell meter on the ign and strapped to the windshield, and as soon as the advance started the dwell dropped to nothing. Long and short was the shaft bushing were shot and it needed a distributor. Also make sure the mechanical advance is free and the weights can move the shaft. Use a mighty vac to test the vacuum advance. It would act like fuel, stubble and back-fire with an occasional after-fire. I had to farm out the valve job because the place I was working, caring for their fleet, the bus took up the whole shop and was very difficult to get it in under its own power, would have been impossible to get it out and back in while the heads were being worked on. There is an old saying that 90% of carb problems are ign problems.

You really need to ascertain if the diff lock's are on or just the light. Side to side locks will be evident if you try to make a sharp turn, PDL (interaxle) will not be quite as evident. None the less I think it is highly unlikely the locks are on and you don't know it. Much more likely a switch or wire is the problem. You can take the air lines off the actuators and throw the switch one way and then the other, you should get air in one position and not in the other. Truck may need to be in "running down the road" (brakes released) condition for this test, so wheels blocked so it can't move. In the years I worked on stuff they could be air apply or air to release (reverse air) but I think everything today is air apply. (IHC and some Dana axles could have reverse air) I don't know about Mack axles. You will likely need wiring diagrams to track down how the light is lit and which wires to look at. Running around in the locked position will cause excessive tire wear and long term will damage the diff's so get to the bottom of it.