'53 International R-172 questions

Just picked this thing up last weekend. I want to order manuals but have a couple questions first. I did get it running already; it's not charging, needs a fuel pump or pump rebuild kit (currently gravity-feeding from a 1-gallon can sitting up on the cowl), needs an oil change, probably needs a thermostat, bad brake line on right rear so currently no brakes....

The gentleman I bought it from said the engine had been replaced and that this is a 308 out of an International bus. He was honest regarding everything else about the truck so I have no reason to doubt him on this. But I do need to positively identify the engine before I order manuals and common maintenance parts.

Regarding the engine: there's a small pad on the left (driver's) side of the block at the front but nothing stamped there. There is a number roughly in the center of the left side but it's quite hard to read. I've only used a wire brush on it. Suggestions to clean it up more? Any idea what this number should look like, what it means, etc? It does have the IH man on a tractor logo down on the left front corner, in front of the fuel pump. What research I've done so far says that this indicates...something... about the lineage? There's also a PR on the block, like way down, left front, by the oil pan.
Really want to get oil filter and plugs but need to nail this down first, I think. There's a sticker on the oil filter canister but some of it has flaked off.

Regarding the generator: only 2 studs, both on top; tag is damaged and hard to read. Are these rebuildable, parts still available? Anyone able to identify the genny from what little info is discernible on the tag? I did a quick YouTube search but there doesn't seem to be much available for testing 6-volt positive ground gennys and voltage regulators. Geez, you'd think nobody's used this kind of system in the last 50 years... (wink, wink). I'm going to look more yet tonight but if anyone knows of a thorough, accurate procedure shown online and can post a link, I would very much appreciate it. I did fully charge the battery, put the meter on it, read 6.41 volts. Started the truck, meter back on battery... a few spikes just above 7 volts but mostly very erratic, reading all over the place from 0.5 volts to 5.x volts. My first instinct is that it's a dirty or worn out genny. I've never been into one but it can't be that hard to do.

Regarding the carb: it says Zenith but I didn't see any other identifying marks. Ideas/suggestions?

There's a broken wire hanging loose. It's in the original loom with the wire that goes to the + post on the coil. Anyone know where it's supposed to go?
There's a red knob under the left side of the dash. It says VAC on it; when I turn it, the knob lights up? What in tarnation is this for??? Is it related to the fact that the wipers do not work and there's a hose dangling unconnected by the circuit breakers on the firewall?
Why is there a wire going from the bottom of the steering gearbox to the relay on the horns???

The mechanical hand brake works, the horn works, she runs, drives and dumps. Needs a bit of tinkering but I'm happy with it. :~)

Thanks much everyone, I do greatly appreciate the wisdom here!

Plain old Delco Remy generator. Parts easy to find. Search here for John T 's troubleshooting guide to walk you through the charging system.

You want all the hoses hooked up. Back then most wipers worked off vacuum.

Looks like quite a project you have there.

Not going to be much help with the engine ID.

You should be able to get a repair kit for the fuel pump, or send it off to a rebuilder. Look online for antique auto parts, restoration, or whatever you are needing. Several will pop up.

The loose wire, it didn't by chance come from the generator? Just have to follow it back, see what the other end is connected to.

The generator is a typical Delco. To test it, ground the F post with the engine revved up off idle. It should go to full charge. Typically the problems are worn or dirty brushes, but more likely there is a regulator problem. If it has an original regulator, guard it with your life! The new regulators are Chinese junk! Ease the top off and file the points with a points file. That will probably get it working.

The wire from the end of the steering gear is from the horn button. Pushing the horn button grounds the wire, which completes the circuit to energize the horn relay.

The lighted knob under the dash, that's a variable speed control for the heater blower.

The wipers are probably vacuum. Find the wiper motor, if it's a crescent shaped aluminum body, they are vacuum. It probably won't work, but they can be rebuilt, another search for antique auto parts.

Be prepared to go through the entire brake system, rebuild or replace all the wheel cylinders and master cylinder, brake lines, and replace the grease seals. If you do it now, maybe you can save the brake linings.

Have fun!

You mentioned erratic voltage on the meter. Digital? They don't work well on DC gens.

I have a 1964 Motor's Truck Repair Manual. It lists the BD-308 engine from 1955 to 1964. Quote from the book: Engine Identification: Engine model takes the form of a prefix to the engine serial number. For example, a V-266 engine serial number would read V-266-000000. Engine numbers are located on machined boss on cylinder block. Hope it helps.

No first hand info, everything I am telling you as far as ID is off the web. It sounds like your 308 engine is verified by the long stem distributor, see reply by Buzzman72 in linked YT post. As far as the oil filter just pull it out and there will be a number on the old one. Same for the plugs, take out an old one and a good parts store should be able to cross it for you. Does it seem to run okay? If so I would not mess with the carb just run it. I do not think you are showing a rear view of the carb that could be where your number is. Seems unlikely that the wire is for oil pressure or a temp gauge, vehicles in that era particularly IH used manual gauges as in a small line actually fed pressure to a gauge in the dash and the temp gauges were capillary tube style that had a brass ..pencil sized.. bulb that stuck into the cool ing system in the head or around the front thermostat housing. A cheap can of carb cleaner can help you clean up the areas where you are trying to read numbers. Likely you know about this but the vapors from that stuff are strong, a good whiff will almost knock you down and it will remove paint. I will add a ditto to the brake repair, working on old truck ..juice brakes.. can turn into an ordeal. Adjusting the brakes up to where they stop a jacked up wheel as you turn it by hand then back off until they turn a half turn then drag is where they should be.
YT post

Just for kicks a link to the Navistar..IH truck engine wiki page.
Poke here

Yes, digital. I wasn't aware that they don't play well with DC generators, will check the local hardware for an analog one tomorrow. Thanks!

It runs decent, considering it wasn't started for 4 years. It does starve for fuel, as I have to keep the choke out a little or it won't stay idling. When I took the sediment bowl off the fuel pump, there was some gray powdery trash in it so I'm sure there's more in the carb.
What you say about the gauges being capillary style originally explains what looks like a capillary tube crimped off in a t-fitting on the heater hoses by the firewall and likely as well the reason for pipe plug in a hole on top of the gooseneck. There's also what looks like an electric temp sensor (not hooked up) on the right rear corner of the head. Maybe had an aftermarket set of gauges at some point? Who knows....
The previous owner said he put all new wheel cylinders on the back shortly before parking it. I think I'm going to start by replacing the one section of steel line that is clearly leaking, fill and bleed the system and see what I've got.

Thanks!

Oh, and will check out the carb a again also....

I'll have to try some chemical means of removing the paint from the numbers I did find. Sure don't want to use anything very abrasive and make it harder to read than it already is.

Thank you!

The loose wire, unless missing a significant chunk (entirely possible) is way too short to reach the generator; gen is over on the right (passenger) side toward the bottom of the block.
I couldn't see any marking by the generator posts. However I want to say one wire was slightly bigger; given that there are only 2 wires, might the smaller one be the field and the larger one power/charge? I did file the regulator points but no improvement. The metal base has 2013 6 volt positive ground printed on it, unfortunately doubt it's an original.

Thanks!

Great to know that parts are available and going to look for that troubleshooting guide now.

Thank you!