Electrical: Distributors: 6V vs. 12V.

[jackb]

My '53 2R6 is starting to hesitate once in gear and accelerating. Doesn't do so in 1st gear so I believe the carb is fine. In the past, I've found this to indicate worn points. Anyway, even if not, here's my question. My truck has been converted to 12 V (+) ground. I read the Delco Remy tag on the distributor and it reads : 1110220. My research tells me that's the correct unit for the truck from the factory. Will that distributor (i.e. points & condenser) work now that its 12 Volts ???

[autoradiotech]

It'll work fine but you need to put a ballast resistor in between the ignition switch and the coil, if you don't the points will fry in about a week of normal driving! You also need to use a 12 volt starter solenoid. Hook it up the way the 6 volt one was and you'll wind up with an extra small terminal on it. That terminal needs to have a wire run between it and the ign switch side of the coil it puts 12 volts to the coil for starting only. Use a ballast resistor for 55 to 58 Chevies, that should be about the easiest one to find, just mount it on the firewall. Good luck. One question, why would you want to go to positive ground with 12 volts? The only thing you would have to change in the wiring is to reverse the connections on the ammeter so it wouldn't read backwards.

[Mike Van Veghten]

Nothing...within the distributor cares whether it gets 6 or 12 volts. Neither the points NOR the condenser care, the cap or rotor care.
The ballast resistor has to cut the power down, so it needs to be correct as does the coil have to be the same as the system (6 or 12).
Verify your ballast resistor and coil.

Mike

[jackb]

I'll check the truck today for a ballast resistor. If not there..... suggestions ? Chrysler ? I've maybe driven this truck 50 miles since I got it last year.

[jclary]

I'll check the truck today for a ballast resistor. If not there..... suggestions ? Chrysler ? I've maybe driven this truck 50 miles since I got it last year.

On hesitation, you have already discounted what, I suspect, by dismissing the Carburetor. There are two things, associated with hesitation, I am familiar with. One, is the accelerator pump, and the other is the vacuum advance diaphragm. Not hesitating in first gear could be due to higher rpms allowing the mechanical centrifugal advance weights in the distributor to handle the work. However, at lower rpm in high gear, the mechanical advance lags vs demand. That's where the vacuum advance, along with the accelerator pump work together. It is possible for the vacuum advance diaphragm to develop a pin hole too small to cause rough idling, but not provide the pull required for compensating inside the distributor mechanism. The ignition timing advance is affected by the instant spurt of additional gas (accelerator pump), and the ability of ignition advance (vacuum pull) to quickly adjust to the demand. Either one of these failing equals hesitation.

This is my humble opinion. I may be wrong. Stay tuned, some more knowledgeable person will help you soon. My sacrificial embarrassment could be your solution.

[PackardV8]

starting to hesitate once in gear and accelerating. Doesn't do so in 1st gear so I believe the carb is fine.

"Hesitate" is a rather imprecise description.

1. Does an application of the throttle cause the engine to flatten out, then begin to accelerate, gaining speed smoothly to top RPMs? That's accelerator pump related. Confirm there's a strong squirt when the throttle is opened
2. Does an application of the throttle cause the engine to mis-fire or run rough all the way to higher RPMs? That's ignition related. When was the last time it had new points, condensor, rotor, cap, spark plugs and plug wires?

jack vines

[jackb]

......to answer Jack's questions and to add some important info: 1st - I haven't found a resistor yet. I don't see one between the ignition switch and/or coil solenoid at all. Jacks ?'s : I got this truck about a year ago. Life/condition of tune up parts are unknown. It has started and ran fine (including single digit temp) these past months until now. I was suspecting no heat valve (CA truck-new exhaust), and cold runs, but I think its not that..... When I step on the gas to accelerate, there is no bogging down until I start to gain some speed, and the engine "sputters"..
in other words: there is no flat spot, just and after - sputter with trying acceleration.... Things do eventually level out unless I try to accelerate in high gear.

[studebakerkid]

Not necessarily do you need a balist resistor....It depends on which ignition coil you use to replace your old one.

[StudeRich]

Wait a minute, it's 12 Volt, but Positive Ground? Why would you make it an oddball setup like that?

Remember with a (+) Gnd. Battery, the Coil has to have the (+) terminal going to the Points not the Negative terminal wire, that is the difference.

[doofus]

might want to check for a weak fuel pump. Doofus

[jackb]

... just a follow up: the points were quite burned up with a lot of black residue about the contact area. In checking through the parts' book, all distributor items are the same for this distributor whether 6V or later Big 6 12 V setups. I have new points in now (shelf item from NAPA) and all is well. Now on to my Overdrive problem. See new post.

[SN-60]

You really need to install that 12V ballast resistor if there isn't one already there Jack....And definitely reverse the ground to negative...Ed

[gordr]

If the truck is running well with 12 volts, positive ground, there is no actual need to make it negative ground. British cars worked fine for many years using a 12 volt positive ground system. The main reason for going to negative ground is for compatibility with modern accessories, and with other cars in the fleet, say in the event a boost is needed.

[Lynn]

Unless you install a resistor, those new points will be burned just like the old ones in less than 1000 miles of driving.

[jackb]

I just checked again. The parts' manual shows the same Big 6 distributor taking the same points, condenser & rotor whether 6V or the later 12V.....I'm getting this info off the CD. Can someone with a better (old) parts' book clarify ??