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Good thing it was a Short Test Ride!

72 Satellite

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Recently got my upgraded dash with new harness, and Gauge LED's installed, and began testing lights, signals etc. Other than a blown 5 amp fuse for the Instrument Display (Gauges), everything else looked OK. Decided to take her for a spin around the block. It was dark and the headlights seemed really dim, I chocked it up to a weak battery. Figured I'd let her run for 10 minutes or so, and see if the Voltage picked up. The Voltage actually dropped, so I shut her down, and started taking a closer look. While looking at the wiring under the hood, I bumped the B+ wire on the back of the Alternator, and noticed an arc. Looking closer and grasping the wire, it came right off with the burnt stud and nut still connected to the wire. Several months back while rewiring pretty much the entire car, along with doing the MAD upgrade, I noticed this connection had some "play" in it. At the time, I thought the insulator-type washer closest to the body of the Alternator was the culprit, not the actual stud/post itself. Pics included for your viewing pleasure. 10 minutes later, while researching a new Alternator to purchase, I noticed I couldn't really find part #'s or markings to identify the fubar unit. Out of curiosity, can anyone tell what unit I had, and what the Amp rating was for it? I ended up putting in an order through Summit for a Tuff Stuff Performance 9509DP unit. Pretty spendy @ $275.00, but looked closest to my previous unit in configuration, fitment etc. As always, any input and/or critique is always welcome. Thanks,

Rob

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I'd have to wonder what kind of internal damage there is inside? What's was the amp output of that unit? Do you want the same output or more amp's? Go to the boneyard and just grab a replacement, or a parts monster or 2?
There's to many open ended questions here?
What is it that you really want as an end result? Good Luck
 
It was gonna be a shot test drive no matter what....
 
Recently got my upgraded dash with new harness, and Gauge LED's installed, and began testing lights, signals etc. Other than a blown 5 amp fuse for the Instrument Display (Gauges), everything else looked OK. Decided to take her for a spin around the block. It was dark and the headlights seemed really dim, I chocked it up to a weak battery. Figured I'd let her run for 10 minutes or so, and see if the Voltage picked up. The Voltage actually dropped, so I shut her down, and started taking a closer look. While looking at the wiring under the hood, I bumped the B+ wire on the back of the Alternator, and noticed an arc. Looking closer and grasping the wire, it came right off with the burnt stud and nut still connected to the wire. Several months back while rewiring pretty much the entire car, along with doing the MAD upgrade, I noticed this connection had some "play" in it. At the time, I thought the insulator-type washer closest to the body of the Alternator was the culprit, not the actual stud/post itself. Pics included for your viewing pleasure. 10 minutes later, while researching a new Alternator to purchase, I noticed I couldn't really find part #'s or markings to identify the fubar unit. Out of curiosity, can anyone tell what unit I had, and what the Amp rating was for it? I ended up putting in an order through Summit for a Tuff Stuff Performance 9509DP unit. Pretty spendy @ $275.00, but looked closest to my previous unit in configuration, fitment etc. As always, any input and/or critique is always welcome. Thanks,

Rob

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IMO....obviously the alternator in question is a 1972 and later square back design. The part that failed is yhe positive diode assembly. On the output connection, there is a shouldered insulating washer that allows the stud to pass thru the case and an insulsting washer that sandwiches the stud that is external with a lock washer and nut to keep the connection tight and a second nut to connect the wire's terminal to tge stud. Since the case is partially melted at the pass thru point, it is HIGHLY unlikely that the positive diode group is serviceable. The prudent thing yo do is replace the unit with a rebuilt, NOS replacement (search on line or eBay...they can be found). There is some controversy as to the QUALITY of rebuilt alternators and where or who did the rebuilding and what components were replaced. The origional capacity is stamped on the frame along with part number and manufacturing date. Do you require any extreme loads or is the vehicle stock? I believe the standard capacity is ~ 65 amps at 12 volts but you will need to make that determination. Extreme electrical loads will likely require major wiring revisions and methods.....others will offer their opinions on the "BEST" way to perform the revisions. Just my opinion of course.
BOB RENTON
 
I'd have to wonder what kind of internal damage there is inside? What's was the amp output of that unit? Do you want the same output or more amp's? Go to the boneyard and just grab a replacement, or a parts monster or 2?
There's to many open ended questions here?
What is it that you really want as an end result? Good Luck

Like I mentioned in my lengthy post (too lengthy), I've already committed and paid for the "Tuff Stuff" 9509DP unit from Summit. My car is a mild resto-mod, with a fresh 440 (.030 over, 440 source heads, headers...). I won't be putting any huge electrical demands on the system. Plans are to finish restoring the AC next summer, and a decent stereo, other than that pretty much stock. Thanks,

Rob

Screenshot_20220219-190043_Chrome.jpg
 
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IMO....obviously the alternator in question is a 1972 and later square back design. The part that failed is yhe positive diode assembly. On the output connection, there is a shouldered insulating washer that allows the stud to pass thru the case and an insulsting washer that sandwiches the stud that is external with a lock washer and nut to keep the connection tight and a second nut to connect the wire's terminal to tge stud. Since the case is partially melted at the pass thru point, it is HIGHLY unlikely that the positive diode group is serviceable. The prudent thing yo do is replace the unit with a rebuilt, NOS replacement (search on line or eBay...they can be found). There is some controversy as to the QUALITY of rebuilt alternators and where or who did the rebuilding and what components were replaced. The origional capacity is stamped on the frame along with part number and manufacturing date. Do you require any extreme loads or is the vehicle stock? I believe the standard capacity is ~ 65 amps at 12 volts but you will need to make that determination. Extreme electrical loads will likely require major wiring revisions and methods.....others will offer their opinions on the "BEST" way to perform the revisions. Just my opinion of course.
BOB RENTON

Thanks for the reply. I could only find the date stamp on the frame, nothing else. If it was an original, then it came with the stock 318 in 72. The unit I'm purchasing is higher output, but more importantly to me, should fit exactly as the previous one did both bracket-wise, and connection-wise. Both are dual field, double pulley flat back design, and look almost identical. Thanks,

Rob
 
Then you should be good to go! If anything, put a larger cable going back to the batt would be cheap insurance. Good Luck
 
Then you should be good to go! If anything, put a larger cable going back to the batt would be cheap insurance. Good Luck

Yeah, I was going to change from my 10awg to either a 8awg or 6awg from the Alternator to the Starter Relay/Battery.
 
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