701 Doesn't charge

[Mike'sHorseBarn 3,653]

Fellas I'm at alittle bit of a loss. This 701 has never charged since ive had it. I'm trying to fix it before I go to a show next weekend, the ammeter is new, the starter generator tests ok, and I put on a new made in usa regulator and nothing. I blame the regulator, doesn't the coil facing the camera have to pull the contacts together to charge? If so, its not doing that. Any help would be appreciated!

 

[squonk 47,851]

Clean the mounting points of fresh paint, Try running a jumper from the regulator bracket to battery neg and see if it changes anything

[ri702bill 12,767]

These are "Old School" and the system may need (most likely) to be polarized. Attached is an OLD Delco Remy Service Bulletin..... Info on page 5.

Polarizing "teaches" the current which way to go... and as mentioned, the regulator needs a good ground.

delco_remy_regulator_service 1R-111.pdf

Edited Saturday at 06:43 PM by ri702bill

[pfrederi 21,021]

Every time you start an S/G tractor you polarize it   (applying battery voltage to the A terminal polarizes the genny.)

[Handy Don 17,272]

My experience with “new” regulators is limited to exactly one, but I never got it to work properly. I eventually got an old one at the show that I could adjust and over time have dialed it in.

The coil on the left (from the tractor seat) switches between start and generator mode. It switches over when it sees enough voltage from the generator.

The one on the right manages the generated current going to the battery at its spring-tension-determined voltage. It opens and closes extremely rapidly--in effect delivering charging pulses to the battery.

The manual @ri702bill linked gives the deets.

 

Things to keep in mind...

- a known-accurate voltmeter is essential (I recommend an analog since the sampling rate of many digital meters can be close to the regulator's “make and break” frequency which can cause very misleading readings even with the tractor battery acting as a large capacitor)

- testing (or trying to adjust) the regulator connected to a discharged or weak battery is an exercise in futility. Just using the battery to start the engine draws out a lot of charge and if a coil engine is running, it is also drawing from the battery. It’s a balancing act!

- on my adjustable regulator, when “close” to the correct setting, one turn of a very fine-threaded screw caused over two volts of variation in charging voltage so adjusting by bending the spring bracket on the “new regulator” had me frustratingly chasing my tail

[sqrlgtr 3,685]

4 hours ago, ri702bill said:

These are "Old School" and the system may need (most likely) to be polarized. Attached is an OLD Delco Remy Service Bulletin..... Info on page 5.

Polarizing "teaches" the current which way to go... and as mentioned, the regulator needs a good ground.

delco_remy_regulator_service 1R-111.pdf 1.06 MB · 3 downloads

I have always done this whether it is needed are not IDK. I understand every time you start a S/G tractor it polarizes but still have always done this. It became a habit when I had 69 Sportster with the magneto and no battery (kickstart only) and it was defiantly a must with it. BTW I did this on my 701 also and didn't have any charging trouble but it may have had nothing to do wit it.

Edited Saturday at 09:35 PM by sqrlgtr

[adsm08 4,981]

If you ground the F terminal and it starts over charging the regulator, or it's wiring, is at fault.

 

Try running some very fine sand paper, or a dollar bill between all the contacts inside your regulator. Like @Handy Donsaid they are constantly opening and closing, which allows arcing, which allows carbon build-up. Carbon is not particularly conductive.

[Mike'sHorseBarn 3,653]

Thanks for all the replies, I'll give some of these a try tomorrow!