Quick Tips - Testing your Generator

Generator Testing
If the brushes check OK, do this test:
Disconnect the generator from the regulator (probably easiest to simply take the wires off the generator).
Connect a jumper from DF on the generator to the generator frame. Now run the engine and measure the voltage from ground to D+ on the generator.

NOTE: Some generators have different types of terminals;
verify which is DF and which is D+.



As you increase the engine speed, the voltage should jump up to +35 volts or so (@3000 RPM).
If it passes this test, the generator is good.
(Don't run this test longer than necessary as it will overheat the generator.)
Polarizing
If it fails that test, the generator may need to be polarized.
Leave the jumper wire connected from DF to ground.
Remove the fan belt.
Connect a wire from the battery + terminal to D+ on the generator.



The generator shaft should start to spin.
Don't run this way for more than a few seconds to avoid overheating.
The generator will now be properly polarized.
If the generator did not spin during this motoring test, the generator is likely defective.
Put the belt back on and re-test for generator voltage with DF grounded. If the output voltage is still low, the generator is defective.
About polarizing
Why do generators need to be "polarized". Auto generators need some magnetism to get started. This "residual" magnetism remains in the Field pole pieces even after the engine has stopped.
The next time the generator starts up, the residual magnetism creates a small voltage in the Armature windings. Not enough to charge the battery, but enough to allow the Field windings to draw current. As the Field current increases, the pole pieces create even more magnetism. That makes even more voltage in the Armature, and the cycle continues until the
generator is capable of producing maximum output.
What happens though to a generator which has been stored a long time or is freshly built? The residual magnetism may have decreased to the point where it can no longer get the generator started producing voltage. In the case of a new generator or one which has been mis-treated, the residual may even be of the wrong direction (North and South poles reversed).
Polarization is a simple process used to restore the Field pole residual magnetism and ensure the magnetic direction is correct.
Do regulators need to be polarized?
No, regulators are not polarity-sensitive.
But my regulator came with instructions to polarize it...
These instructions actually polarize the generator, not the regulator. The regulator mfr simply wants to ensure that your generator will work properly so you don't blame the regulator.

Quick Tips: 1959 Edsel/Ford Dual Master Cylinder Swap

Quick tip of the day: If you have a 1959 Edsel or Ford and want to put the bigger dual output master cylinder, use a 1967 Mustang unit. It will be a direct bolt in except for having to change the brake lines.

Note: Ensure you are getting a Drum (F)/Drum (R) master cylinder for your 1959.

Quick Tips - How to Identify Post and Pre War Hydra-Matics

If the original transmission is in the car, and shifting properly, perhaps best to leave well enough alone. But for how long, who knows? Now, possibly, the trans has been replaced with a postwar unit. There have been 60+ years for this to have happened!

The quickest giveaway is to peek down at the transmission from the drivers side of the engine. On the postwar models, there is a large Hexagonal plug-like thing at about 1:00 on the transmission as youre viewing it. Thats not there on the prewar transmissions. Its the pressure regulator valve.

On the controls, the selector detent is entirely in the steering column hub, where the indicator is on the prewar models. If the detents are light and not sharp, its a prewar box. The detent was moved to the control valve body inside the transmission after the war, and is very pronounced. Another of the many improvements made in 46 was the addition of a "reverse blocker piston" in the control valve body. This keeps you from yanking the lever into the reverse position until after the transmission engages. Even then, the rear wheels must be OUT OF MOTION before you can drop it into reverse. Whats happening here is that the drum of the reverse planetary must be stopped for a pawl to engage it and lock it. That wasnt there on the prewar jobs, and many a reverse planetary and reverse pawl were chewed up.

In order to make the transmission easier for rocking the car in snow or mud (Heaven forbid!) a new cone clutch reverse engager was incorporated in the transmissions from 1951 on. I have a 51 transmission in one of my 41s, and you can yank the selector into reverse as soon as the engine fires, with no problem. On that one, the 2-3 upshift is a little brutal, but I can live with it easily. The other two 41s have 49 Cadillac boxes in them, and Ive never driven a more enjoyable transmission.

Quick Tips - Grounding

Grounding is an important aspect to all vintage car electrics, especially in a 6volt system.

A few helpful tips to expand your grounding for a 'longer' life span on your existing system.

1. Every once in a while, inspect your battery and body grounds. Remove them, clean the posts and the surfaces they are attached too.

2. Make sure you have FRESH bare metal that your grounds are connected to.

3. Use a wire wheel to clean all your ground surfaces. I use a wire wheel cup and cordless drill.

4. Use a anti-corrosion gel on all ground connections. Gives longer life.

5. Add a separate ground from your frame to body. I always put one on the front and rear of body to ensure good grounding throughout! Use #6 wire or Flat mesh grounding strap from your local parts house. Go to Step #6.

6. Always use round eyelets for all grounds (see picture above) on all grounds. There is a much larger surface area which is needed for a good ground.

Quick Tips - Gas Guage Operation

One of the biggest mysteries is making sure the gas guage is working properly. Nobody wants to be stranded out of gas. Knowing what's in the tank gives that sense of comfort while driving - it's a great feeling.

Here's a quick test that will put that mystery away.

This process can be applied to all cars except those with computerized gauges.

1) Ensure your gas guage as power to it. Check the fuses to be good or put a test light on the terminal (with the ignition on)to ensure power is there.

2) Locate the fuel sender feed wire near the fuel tank. You're looking for a single tan (typical colored) wire. With the tan wire disconnected at the fuel tank, the fuel gauge should read past full with the ignition on. Wait a few moments as some fuel gauges take a time to respond. Touch the tan wire from the body to any good convenient ground and the gauge should read empty. If not, you have a wiring problem or a bad gauge.

3) If the gauge responds correctly, the gauge and wiring are OK. Next use a multi-meter to measure resistance to ground of the sender wire connection on the top of the fuel sender or the "tan" wire from the top of the fuel tank. Measurements should track the fuel in tank.

(Estimated - These are GM Figures)
Just know, with the fuel gauge at empty, you get 0-2 ohms. With the guage full, you should have a reading up to or above 88 ohms.

Full - 84-88 ohms
Half - 40 ohms, give or take
Empty - 0-2 ohms

If this doesn't check, then sender or wiring on top of the tank is bad or the sender not adequately grounded. Senders are typically grounded by a black wire which is welded to the sender and attached to the body with a sheet metal screw. Also know, some senders are grounded directly to the tank itself. If sender needs a good ground; a quick fix would be to remove one screw from the sending unit, clean the surface of the sending unit; make a lead using an "O" or donut termial on each side and install proper. Make sure your ground is to good bare metal. Use a drill with a wire brush to clean your ground surfaces.

4) If the sender checks OK but gauge and wiring don't, clean the connections, reconnect the sender wiring. Again, when removed the gauge should then read past full. Ground the tan wire on the dash side and the gauge should read empty. If not, you probably have a bad gauge or possibly a dash wiring problem.

5) If the gauge checks OK, then make the same resistance checks to the "tan" wire in wire loom. If it checks bad, inspect your wiring or run a new wire to replace. Its common to have old wiring crack and ground out on the body, creating issues unseen.

In Conclusion; the gas guage must have a good ground and good wiring to operate properly. Its always good to remove your old sending unit and clean it good with electrical parts cleaner or carburator cleaner. When you have it out, make sure the float is in good shape and is 'gas' tight.

Good Luck and Motor On!

Quick Tips - Banjo Rear to Axle Hub Tight Fit

Ever wondered how to fine tune the fitment between the rear axles and the hubs?

I was told a simple method to clean up the hub tapered surfaces to get a nice tight fit.

Alot of the banjo rears we pickup these days have good clean surfaces, but its unclear by the human eye to determine. A friend told me the best way to do this is to use some valve lapping compound and a little elbow grease. Remove the woodruff key, apply a generous amount of compound on the surface and rotate the hub in 45 degree increments. Use moderate to heavy pressure until the surface is clean. This process will get rid of any rough surfaces, rust pitting and abnormalties.

When finished, torque the nut in place and step on the gas!

Motor On!

Quick Tips: Cleaning inside of tubes

Heres a quick 'How to' to clean the inside of pulleys and tubes. Take your cordless drill and wrap some steel wool around your drill bit. Polishes the inside nicely!

Quick Tips - 55 Chevy Brake Master Cylinder Replacement

Quick Tip: If your building a 1955 Chevy and are going to run the stock drums; replace your master cylinder with a 1968 Chevelle drum/drum master cylinder. This will give you a dual output for independent control for front and rear drums. Adds a surety of safety to your Hot Rod.

Look for VM Tech Article on this installation.

Note: Sample Photo of Chevy master cylinder