1948 International 2 ton (maybe 1 1/2 ton) with the straight 6. I was tasked with installing the rebuilt original fuel pump. It pumps, pulled #1 plug no fire, pulled coil wire no fire. Obviously it could be a bad coil but I don't want to just throw parts at it. Could also be a bad condenser or maybe the ignition box. The ignition box has 3 contact points, top says BAT, center says ARM and bottom says FLD. The bottom one is disconnected and the wire is hanging taped off. It heads towards the generator. Since I'm in a field and not at home and don't have a multimeter on me, when I come back out how/what do I check next?
Field Coil Check Get 2 jumper wires Unhook both wires from coil The one that went to the distributor is the 'ground' side of the coil, attach jumper to that side (loose) Attach jumper from other side of coil to battery Touch 'ground' jumper to ground, should see spark when you break connection to ground, that is when coil should throw a good blue spark I'm pretty sure those old IH's are positive ground (does not affect the test), just for info
if your points and condenser are bad there will be no spark at the coil. the ignition box you are referring to is actually your voltage regulator for the generator. has nothing to do with ignition
Correct as for as it goes. The spark you are looking for in the test described above is from the coil wire that leads to the distributor cap. Pull it from the cap and hold it about 1/4" from a good grounded metal surface. The spark should jump that gap. However, you could easily have a contact point problem. The contact points would be dirty or pitted. Have you examined them closely? Turn the engine to a position where the points are closed. Insert a piece of stiff paper, business card, or some such that is clean and wax free (no candy bar packaging). and withdraw the paper. dragging between the points. That will usually clean oil or dirt from them. If badly pitted, well a file would be handy, but at worst, just make sure you have a opening between them when the rubbing block is on the high place. You can test for the points working the same as above but with one difference. Keep the jumper from the coil - terminal attached and with the points closed, open the point contacts manually. If everything is working, you should get the spark from the coil wire as indicated above. Careful what you use, a non conducting item, plastic or wood (pencil/pen) prevents accidentally grounding the points and 'blowing' the test procedure. The item you describe as the "ignition box" has nothing directly to do with the ignition. That is the voltage regulator and is the control unit for the generator. But that's a whole 'nother problem Good luck! Ray Studebaker 46 types faster than me!
Okay Dave, I'm jumping from the battery to the battery side of the coil (battery is under the floor at the running board) and a jumper from the other side of the coil to ground. Of course I'll check for positive or negative ground and do the opposite. I did pull the coil wire from the disty and arced the solenoid which is how I found out it didnt have fire. I know about the points and condenser but I knew I had to make sure the coil was seeing electricity and wasn't sure what it did on those two connections. So what it is is a switch right? When the points close, the condenser sends a signal to the coil to fire? And when they open the condenser charges?
Ray, I did the first part already. If after I do Dave's test, I'll reconnect the disty side? to do the points test? I sort of remember this stuff from 20 years ago when my 65 Stang was on the road. And my 73 F100 has electronic distributor in it. When I finish my 63 Fairlane drag car it'll likely have a crank trigger.
This likely won't happen until tomorrow as I don't have a long enough battery jumper around. Besides I'm struggling with a Thermoquad on a 79 Lil Red Express Truck (I hate emission carbs!!!!) okay, any Thermoquad experts? The pump is not shooting. Obviously I need to check the diaphragm on the bottom of the pump ***embly but Im not sure where the pump gets its fuel or how it gets out. The carb is just to big for a Berryman's can so I shot the ports with carb cleaner, musta missed some. Freaking E10.....
The condenser does not act as a signal to 'fire' the coil. The way it works is....current is routed to the coil + terminal and travels through the coil primary windings and exits the coil through the - terminal and is connected to the distributor ignition points. The points act as a switch to permit the current to flow the through the coil primary windings......causing a magnetic field to be generated around the coil. When the points are opened (switch is opened) by the distributor cam the current flow stops, the magnetic field collapses, p***ing through the coil secondary windings and induce a high voltage surge through those secondary windings that is discharged from the coil tower wire into the distributor center tower and via the rotor to the appropriate spark plug. But, back to the condenser.....it serves as sort of 'alternate path' for the current flowing through the points when the points are opened. Were it not for that alternate path, the points would always be arcing as they opened and closed and burned up rapidly. The condenser does get 'charged' in the process and discharges itself when the points next close...and the process repeats itself over and over. As for the carb.......usually the gas flows into the bottom of the accelerator pump 'well' or chamber through a ball check valve in the bottom of the well. When the pump plunger is pushed downward the inlet check ball is closed and the fuel exits through another check valve into a p***age and is discharged into the air stream in the carb throat. Carb cleaner and compressed air are you friend and blowing through the two check valves to clean them is usually helpful. Sometimes the inlet check ball has a plug in the port that is threaded and can be removed with an appropriate sized screw and a hearty tug. I am not very familiar with the Thermoquad and am ***uming it has the plunger style accelerator pump. But, if it is a Ford style square diaphragm type, the operating process is the same, it just looks a little different. Ray
Perhaps.......but if it has an accelerator pump, and I believe it does, it has some sort of check valve ***ociated with filling the accelerator pump chamber with fuel. If the pump well does not fill adequately, or at all, the check valve, in whatever anthropomorphic form it replicates, is where the problem likely is located..
Okay, updates. International ended up having a bad coil to cap wire. Took one off my car and it fired right up. Purrs like a kitten. Anyone know what 6 they had in them? LRET Thermoquad: It DOES have....ball. The cap on the bottom of the squirter has a check ball captured in the cap itself. It allow the piston to rise so as to not pull a vacuum in the pump cylinder. It just doesn't have any loose balls. Anyway, turns out the pump rod floats in the cup retainer and it wasn't rising above the window to allow fuel into the chamber. It was ****ing air back from the shooter and what little the ball let in. Not enough to prime with. Oldguard helped me out figuring it out.
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