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JoeHall
09-22-2017, 05:31 PM
I recently read a thread here about rotor failure in a 57GH, and thought, what are the odds of that ever happening? Well, today I received an answer, when one failed on the 63GT. I was out putting the first 50-60 miles on the new brake job, when the motor suddenly shut off. I was able to get off the road by whipping it into a farmer's field access driveway. Then, after some head scratching, I pulled the distributor cap, and discovered the problem: it looked like the corner of the rotor's brass ear, that passes by the distributor cap's plug wire contacts, had snagged one of the cap's contacts. In doing so, it chipped the corner of the rotor's plastic, and the resistor was no where to be found. I had a spare, used rotor in the trunk, and it got me home.

Once home, for grins, I cut a piece of wire just the right length, and stuffed into the slot where the resistor was. I then filed the corner on the brass ear, to round it off a bit. Once reinstalled, the motor fired right up. However, it lost 5-6 degrees of timing. I am thinking by rounding off that brass ear, it retarded the spark.

Later tonight, I plan to put a dab of JB Weld on that wire, to insure it does not move, then see how long it will run that way. I have noticed over the years, it is common for that rotor's ear to wear grooves in the cap's contacts, but never seen one snag and break like this one did.

Sure glad I had that other article here, still fresh in my mind today. Here is it: http://forum.studebakerdriversclub.com/showthread.php?102589-57-Golden-Hawk-distributor-rotor-construction

BobPalma
09-22-2017, 06:27 PM
I recently read a thread here about rotor failure in a 57GH, and thought, what are the odds of that ever happening? Well, today I received an answer, when one failed on the 63GT. I was out putting the first 50-60 miles on the new brake job, when the motor suddenly shut off. I was able to get off the road by whipping it into a farmer's field access driveway. Then, after some head scratching, I pulled the distributor cap, and discovered the problem: it looked like the corner of the rotor's brass ear, that passes by the distributor cap's plug wire contacts, had snagged one of the cap's contacts. In doing so, it chipped the corner of the rotor's plastic, and the resistor was no where to be found. I had a spare, used rotor in the trunk, and it got me home.

Once home, for grins, I cut a piece of wire just the right length, and stuffed into the slot where the resistor was. I then filed the corner on the brass ear, to round it off a bit. Once reinstalled, the motor fired right up. However, it lost 5-6 degrees of timing. I am thinking by rounding off that brass ear, it retarded the spark.

Later tonight, I plan to put a dab of JB Weld on that wire, to insure it does not move, then see how long it will run that way. I have noticed over the years, it is common for that rotor's ear to wear grooves in the cap's contacts, but never seen one snag and break like this one did.

Sure glad I had that other article here, still fresh in my mind today. Here is it: http://forum.studebakerdriversclub.com/showthread.php?102589-57-Golden-Hawk-distributor-rotor-construction

:o Joe, does your '63 still have a Prestolite distributor in it? If so, the shaft bushings may be worn enough that there is sufficient "slop" in the shaft that it is allowing the rotor to go out, too close to the distributor contacts. :eek:

(Are you coming up to Mike Baker's Open House Saturday the 23rd? 'Hope to see you there.) :cool: BP

JoeHall
09-22-2017, 06:42 PM
:o Joe, does your '63 still have a Prestolite distributor in it? If so, the shaft bushings may be worn enough that there is sufficient "slop" in the shaft that it is allowing the rotor to go out, too close to the distributor contacts. :eek:

(Are you coming up to Mike Baker's Open House Saturday the 23rd? 'Hope to see you there.) :cool: BP

Bob,
All my Studes are converted to DELCO, the kind used from 51-59 or so.
Wish I was coming to Mike's Open House. I need a couple of clones. LOL
Thanks,
Joe H

Ross
09-22-2017, 07:52 PM
Over the years I have witnessed tooooo many failures of those Delco rotors with the resistors. Substitute the equivalent year's Pontiac rotor, Napa Echlin RR157 which has no resistor.

JoeHall
09-22-2017, 08:47 PM
Over the years I have witnessed tooooo many failures of those Delco rotors with the resistors. Substitute the equivalent year's Pontiac rotor, Napa Echlin RR157 which has no resistor.

Thanks, I am gonna do that!

Joe H

Bud
09-23-2017, 07:40 AM
I've been using rotors that were specified for mid 50's GM cars such as Oldsmobile and Buick to replace the Studebaker rotors with the trouble prone carbon rod. The GM rotors do not use a carbon rod which is not necessary to reduce ignition noise in the radio as most plug wire sets now have a suppressor core. The part numbers I have been using are either Ampco DR949 or Standard DR309. As a plus, the GM rotor is about half the price of the stock rotor. Bud

jclary
09-23-2017, 08:45 AM
Anybody have an easy to post pic of the rotors in this discussion? I'm assuming these are NOT the window type Delco distributors.:confused:

Bud
09-23-2017, 04:58 PM
The Delco window distributors originally used in the 59 to 61 V8 Larks used a rotor with a carbon rod so they are also susceptible to having the carbon rod flying off of the rotor. My advice is to use a more modern rotor designed for most V8 equipped GM cars from 1956 to 1974. They don't use a rotor with a carbon rod and are bunch cheaper than the rotor specified for Studebakers. Bud

JoeHall
09-23-2017, 05:18 PM
I've been using rotors that were specified for mid 50's GM cars such as Oldsmobile and Buick to replace the Studebaker rotors with the trouble prone carbon rod. The GM rotors do not use a carbon rod which is not necessary to reduce ignition noise in the radio as most plug wire sets now have a suppressor core. The part numbers I have been using are either Ampco DR949 or Standard DR309. As a plus, the GM rotor is about half the price of the stock rotor. Bud

Thanks Bud,
I just ordered one each of those numbers, NOS, off ebay for less than $7 each, including shipping :)
Thanks Again,
Joe H

acolds
09-23-2017, 07:57 PM
When I purchased my Clipper the inside of cap where worn away from the rotor contacting them. At first I thought it was a worn shaft bearing after checking found the rotor itself was loose on the shaft the shaft was correct the replacement rotor hole that fits onto shaft was oversize. Installed NOS Delco I had no more contact between rotor and cap. Seems many replacement parts are sub standard or suffer from poor quality control

Jeffry Cassel
09-24-2017, 02:16 PM
I'm not sure rotor failure is a new phenomenon. I had my 61 Hawk since 1970. Probably no longer than one year after aquiring the blue bird it suddenly began to run very badly. We limped into the base auto hobby shop where I quickly found that the end of the rotor was completely burned off. Coundn't see how it could run at all. It was an American made Delco part. This was long before Tricky Dick went to China and opened up our country to the tons and tons of garbage they send us.

JoeHall
09-24-2017, 02:31 PM
I'm not sure rotor failure is a new phenomenon. I had my 61 Hawk since 1970. Probably no longer than one year after aquiring the blue bird it suddenly began to run very badly. We limped into the base auto hobby shop where I quickly found that the end of the rotor was completely burned off. Coundn't see how it could run at all. It was an American made Delco part. This was long before Tricky Dick went to China and opened up our country to the tons and tons of garbage they send us.

I wonder if the rotor resistor is to reduce burning of the metal contacts, including the one on the rotor and the eight inside the cap. The clearance between rotor metal and cap, by design, is close, probably only a few thousandths. Most every cap, after a few thousand miles, has had the terminals corroded, and often grooved. I usually replace the cap, and gently clean the rotor. In NOS rotors, the resistor is only held in place by a spot of epoxy. But I have a repro rotor, made in Mexico, that simply has a brass rod in place of the resistor, completely buried in clear epoxy, which is so strong it would take a dremel to remove it.

Bud
09-24-2017, 03:10 PM
The resistor in the rotor is used to reduce ignition noise in the radio. With the advent of suppressor core plug wires, the resistor is no longer necessary and as a plus the resistance built into the newer style wires also reduces wear on the cap, rotor and spark plug contacts. I learned in the late 60's when I had my Power Hawk to replace the rotor with one meant for GM cars when the carbon rod flew out of the rotor and left me parked on the side of the road. Bud

Skybolt
09-24-2017, 07:32 PM
Something I had not thought about, the carbon rod theory, sorry just had to laugh at a story line or something, anyway, as my first Studebaker was a 20 year old 61 Lark station wagon, with 259 V8, something indeed out of the ordinary, I didn't even know of that difference in rotors. Maybe it never concerned me because all the rotors I used were the cheaper ones, so we thought, with the brass/copper spring like contact on top and not the carbon ones. I do keep a few of each around, if I can, so as to period date stuff, but I use the most reliable and lightest I have in stock for myself, for the road.

Len