Can I start the engine briefly without the alternator?

As some of you may have noticed, I have been trying for months to find the cables for the alternator. Unfortunately, they are always out of stock, even at NPD for the 70 AMP alternator. But I have to get the car off the lift and want to test if the other cables and repairs are correct. Can i run the engine without the alternator and its wiring for a short time without damage? the optima red is fully charged, and the wiring is ready to go, e.g. to the starter and to the ground on the engine block.

Thanks
Ben

Yes, Car will start and run for a while just with the battery powering the ignition system. No damage should occur. It is similar to the alternator failing while driving, the car will run for a while gradually drawing down the battery.

Many a car has been sent down the drag strip with no alternator. Bracket race and circle track guys commonly don't run one, up to like 100 laps.

One thing to look out for is your belt routing. In some setups, the alternator belt is what runs the water pump. Make sure you have a belt that spins the water pump, or dont run the car long enough to overheat.

If you're interested in a "previously used" set, I have the front harness I purchased from 172Mustangsprint here on the forum. I removed the Sport lamp connections, but the remainder of the harness is intact. Just PM me and we can work it out.

As far as your question, I'm 99% certain about the wiring part but without an alternator, 100% certain Yes. However, if memory serves me, I'm thinking you may need to run a jumper from the Voltage Regulator to the distributor?

Seems to make sense that if there's no alternator connected, the wires wouldn't be needed, and I mention that since drag racers rarely (if ever) have alternators since it scrubs some H.P. off the motor. So, stands to reason no wiring is required either. Yeah, even with the insane 11,000h.p. Drag race engines of today, that couple of horses makes a difference.

Also, a bit of un-necessary "knowlories"(useless knowledge from memories), can't remember the cut-off year but you can actually disconnect the battery, while the car is running with a functioning alternator installed. I mention a "cut-off year" because I vaguely remember that became impossible at some point in time over the years. There was a time, even when gas was at $0.47.9gal, those of us who had 4spd cars and only enough money for gas, but not a new battery, opted for gas since we could push-start the car. When the passengers would chip in cruise-night, it always worked out well, especially with 2 or 3 if the car stalled on a flat area, more push power! Lol. Speaking from my original hometown, the majority of the Saturday night racers on 79th street/Des Plaines Ave./Rt.83 had no alternators, only batteries.

Either way, bring the tape to insulate any open positive leads otherwise you'll short something. It may be a 12v battery but remember it's the amps that make the magic happen, especially a H.P. battery with near 1000cca., it's wise to just leave positive leads connected and disconnect from the negative side.

Thank you very much for all your fast responses. I will have a more profound look at Friday and the tip with the water pump, of course, was critical. And then we will see. Take some new shots in the project channel after this.

Hi guys, today I tried to start the Mustang as announced. I didn't make it.

I have double and triple checked all the cables, the battery is fully charged.

After I switched on the ignition, the car remained completely silent.

Neither the starter motor nor the dashboard displays or the radio responded.

The car remains practically "dead" despite the charged battery.

Today we also took measurements of the battery, the negative terminals on the vehicle and the engine block.

We have also checked the contacts on the starter relay and also tested the ignition lock, and there too we were able to measure infinite ohms and also the 12.8 volts of the battery.

Can you make any sense of why the volts and ohms match but there is obviously no action? Bit frustrating.

The alternator wiring is further not delivered so not connected.

Thanks Ben

Have you tried "hotwiring" the ignition? Run a lead from the(+) side of the battery to your coil to turn it on, then just "jump" your solenoid to crank it. If you have fuel and correct timing, you should start up. From there, you know the engine components work, and the issue lies elsewhere in your electrical wiring or components.

The fat yellow wire provides electricity to the inside of your car, ignition switch, lights, gauges, etc. Check the voltage at that point. You may have a fusible link that is fried.

Don C said:

The fat yellow wire provides electricity to the inside of your car, ignition switch, lights, gauges, etc. Check the voltage at that point. You may have a fusible link that is fried.

Click to expand...

Don makes a good point. From your picture does your yellow wire mounted on your terminal block have battery voltage to it? If not try moving it to your battery post of your starter relay.

I would be careful about connecting the yellow wire directly to the battery terminal on the solenoid. If you have a short someplace you could fry some wires, or even start a fire. I would connect a 30 amp fuse inline.

Thanks for all your tips. I always thought the yellow cable was for the defroster and was then secured with a 14g fuse.

There are two yellow cables. One is from the main wiring harness and the other is for the defroster, as far as I know.

But I will test exactly what you have described with a fuse in between.

I also have a 20 amp fuse from the starter relay to the black wire for the automatic windows, like the original.

How can I tell which of the two yellow cables gets the 14g fuse and is attached to the starter relay, and which of the yellow cables is attached to the terminal block?

Both are labelled 37, is the thickness different so that I can distinguish one cable from the other?