Merle Coggins

@WPVT Earlier you stated that you believe your mechanical advance and vacuum advance are both working properly, but you get detonation at higher speeds. It may be worth while to double check your vacuum advance unit. Years ago I started having a detonation problem with my truck at higher speeds, especially under load such as climbing hills. Eventually I found that my vacuum advance worked, but also leaked. This vacuum leak seemed to cause a lean condition which led to the detonation. After I replaced the vac advance unit (purchased from Kanter) and gave it a good tune-up, it ran great again.

You had your foot depressing the clutch pedal? If so, even it it jumped into gear it shouldn’t have lurched forward. I think it’s time to get under the car and start your inspection with the clutch, then work your way back.

I don’t know if the specs changed for your C1B, but here is a look at the specs for a B-series truck. It looks like 21 degrees total. 10 degrees mechanical and 11 with vacuum. You might be able to find an advancing timing light hanging in the tool isle at your local parts store. They’re pretty common. It may require a 12v supply. If your truck is still 6v you could use any 12v battery for a power source.

Do yo have a timing light that can adjust to measure the advance? I suspect that one of your mechanical advance weight springs is bad and you’re getting way too much advance over 2000 RPM.

Exactly… I made the mistake of forgetting to remove the rotor one time while doing the adjustment while cranking. The rotor came around and knocked the screwdriver out of my hand, which also broke the rotor. Luckily I had a spare on hand.

Those are probably aftermarket pumps that they decided to save expense by eliminating the retainer and screw and make the check valves a press fit.

I have checked and adjusted the dwell while cranking. Remove the cap and rotor, loosen the points adjustment screw slightly, crank over engine and watch dwell meter while making fine adjustments. Lock everything down when you have it where you want it, reinstall rotor and cap, fire it up and double check the dwell.

I believe there’s a small gear box behind the speedo that shifts when the rear axle shifts to account for the gear ratio changes.

I suspect he had a problem with the vacuum shifting because he lacked the valving and plumbing to make it work after he swapped the axle into the truck.

Someone snuck a green 'Dear John' tractor into the Red Tractor parking area. ? As they say... "Nothing runs like a Deere." But also remember that 'Nothing stinks like a john.' ?

chrysler1941 is showing the switch setup on cars. The truck switches are different. By the pic above it shows that he has the escutcheon loose already (of which there is also a special tool for) but he can't get the knob off. And as already stated, the knob will screw off, but the center of the knob shouldn't turn with the outer part. The center piece is 'keyed' onto the switch shaft so that the writing sill always be correctly orientated. Often times the centers get stuck to the outer shell making removal that much more difficult.

Are you sure your truck has a 2 speed axle? Does it have the vacuum chamber at the rear axle like Wally showed?

Since you'd have to take it off to replace it, why not take it off, clean it up, and hammer out the dent?

And I believe your wheels should be black. They started the Dodge Truck Cream (yellow) on the wheels with the B2 series trucks.

Here is what the Parts catalog shows. My B2C has the 15" X 5-1/2" wheels and I recall that it had 6.50-15's on the front and 7.00-15 tires on the rear.

My daily driver looks like that just about every morning.

Yes, and the screws that attach the gauge to the gauge housing.

Is the gauge itself properly grounding through it’s mounting? There are 2 electro magnets inside the gauge. One that is variable, connected to the sender. As the float rises the resistance goes down which makes that magnet stronger. This magnet pulls the needle towards “F”. The other magnet is grounded through the mounting and provides a steady pull on the needle towards “E”. If you don’t have a good ground for the gauge you won’t get the pull towards “E” and your gauge will not come off of “F”.

Looks smaller than the 4 speed trans. Maybe a 3 speed? Did 3 speeds have a PTO option? Also, I don’t see the New Process logo on the case that is common on the Dodge Transmissions.

Ahh... I read that but didn't fully understand the reference. I now also see the yellow plug where it will connect.

No brake line to the left wheel?

In North America that would be a 1948-1950 B-Series truck. But in Australia they changed model designs in different years, so it could be a later model. Hopefully some of our Aussie members will chime in soon to help you out.

Once you get past Speed 9 bad things will happen and you'll end up at Speed 0 again. ?

Take a piece of rope and pass it through the seat, where the seat belt will come through on your right side, until it reaches your planned anchor point. Then sit in the seat and put the rope over your lap and route it to your other anchor point. Mark the rope, remove it, and measure the length.

I've done a few trips with my truck where I ran a sustained 3000-3500 RPM for several hours without issue. But I also know the condition of my engine as I built it. I agree with Jeff. A few years ago I started experiencing detonation "ping" at higher RPM under load. It did have a bit of a "clatter" sound. I kept telling myself, "One of these days I'll get around to investigating it". Eventually it knocked the electrode center out of a couple of spark plugs causing a serious loss of power. I found that I had a bad vacuum advance causing a vacuum leak, which likely leaned out my air/fuel mixture leading to the 'pinging'. After replacing the vacuum advance and spark plugs, and adjusting the valves, all runs good again. In hind sight it could have been much worse than a couple of failed spark plugs. You can damage pistons, wrist pin bushings, and/or con rod bearings due to continued operation with serious detonation.