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Discussion Starter · #1 ·
I have a 1967 xr7 , car was turning over in 1 second , slowly car was taking long to start , drove it to store and felt weak and stalled out. Tried to restart and battery was dead . Put in new battery and started right up for a day or two after taking it for another drive I had same issue . I replaced the alternator and charged battery started right up, again for a day or 2. Took car for another drive and had same issue again , long crank to start and car feels like it wants to stall , until it is on the road at speed. Does anyone have any idea what I could check. Volt regular , alternator cables ? Thanks in advance .
 

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Discussion Starter · #2 ·
With voltmeter checked battery with car off read 12.6 and with car running read 12.3 , what would cause alternator to not be charging battery ?
 

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To test the alternator, you need to excite the circuit by revving the engine above 2000 rpm. Turn on the headlights, stereo and heater blower to place a load on the electrical systems. Next measure the voltage at the Bat post on the back of the alternator or at the starter solenoid Battery terminal. This should measure between 13.5 and 14.5 volts.

If the system reads only 12 V, basically battery voltage, then disconnect the plug at the voltage regulator. Using a jumper wire with male connectors on both ends, place one end in the F terminal connector and the other end on the A connector. This effectively bypasses the voltage regulator and provides full excitation to the alternator. The voltage reading at the bat post should now read 15V. If it still reads only 12 V, then the wires to/from the alternator and the regulator are suspect.

Attached is my pdf file for the 67 Cougar charging system. Note that the wiring at the alternator and voltage regulator are different for a standard Cougar (indicator lamps) and an XR7 (ammeter).

1967 Cougar charging system in depth.pdf

Let me know if you need any additional information.

coachJack
 

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Discussion Starter · #5 ·
Thanks just bypassed the voltage regulator and I was getting over 13 volts so either the pigtail or regulator are bad. I am going to replace both. Thanks again
 

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Discussion Starter · #6 ·
Replaced voltage regulator but engine is still not turning over right away. Alternator is charging battery now . Is 13 volt for a non running battery bad ? I know should be about 12.6v. Just drove to store and had issue turning over and felt low on power. Strange usually with a fully charged battery or runs great. Any ideas what I could check next .
 

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Your alternator should be putting out 13.5 to 14.5 volts. You should also charge your battery overnight on a trickle charger to make sure your battery is fully charged. When the car is running, the alternator should put out more than enough voltage to run the vehicle and provide the battery a charge.

There are a number of things that can cause issues with your engine turning over which includes the following:
1. Yes a weak or undercharged battery
2. Engine overheating causing vapor lock
3. Engine timing, make sure it is not too far advanced
4. Carburetor choke not adjusted properly
5. Timing gear/chain skipped a tooth
6. Exhaust system plugged up
7. Make sure your battery cables are clean and tight and all of your Grounds as well.
8. Starter motor itself could be full of carbon buildup. You can take the starter off and have it bench tested.

coachJack
 
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