As I sit here removing head studs from my case halves wondering what the hell I have done with engine parts scattered over several square feet of my cellar, I decided I would do the initial cam break-in on my engine/tranny dolly.

How does one connect the alternator? The alternator has one heavy gauge wire that goes to the starter and a 3 wire plug that goes to the voltage regulator on the relay board. Is the relay board/voltage regulator needed for the engine test stand?

It's not necessary to hook it up at all unless you really want to. I break-in all my motors on an old battery I have here at the shop on my test stand. Once the motor is started it takes very little power to run it. I imagine that you could run a motor for several hours on a well charged battery. To hook up the alternator correctly would just be more wiring for no good reason IMHO.

I agree, if you have doubts as to the functioning of the alt it would be easier to take it to your local auto parts store to be tested. My test stand has a regulator and light installed because I test several engines a year, but for the occasional home test I wouldn't have gone to the trouble of finding a regulator and plug to wire into my stand.

I once drove from ABQ, NM to Jerome AZ on just a battery, so it should have no problem lasting you for the entire break in period.

When I tested my engine on a stand, I just used the car battery connected using jumper cables and connected my battery charger to the battery to maintain battery voltage and charge.

I wouldn't connect the alternator unless you bolt in the battery connections. Connecting the way I did with jumper cables may allow momentary disconnects of the battery during testing. If the alternator is connected at this time, it is possible to damage the alternator by what is called a load dump. Load dumps happen when a discharged battery is being charged by an alternator and the connection of the battery is momentarily disconnected. This is one of the reasons that a car should not be operated with the battery removed.

Just leave the belt off.

A consensus!! Excellent! Thanks everyone.

Merry Christmas.

Another option is to rig up the relay board with the alternator properly wired up and have all of that on the engine stand.

I have also seen it done with the engine pulled up right next to the car on the drivers side and just plug in there...that way you dont need to make up a wiring kit...just use the car key to start it...

If you search for DNHunt, he shows a few pic of how he did that...seems like the easiest option in my book..


Rich