Pulses per Revolution

I have a 8MR2069TA alternator installed on a Yanmar diesel in my boat and wish to install a tachometer reading from the alternator. The first question the installation guide asks is the Pulses Per Revolution (PPR) of the alternator, which is calculated as the number of Poles times the ratio of the crank pulley over the alternator pulley, divided by two. (PPR=PxR/2) Could you tell me the number of poles in this alternator?

Many thanks


4860 and Isolator

Is it possible to get a 4860JB alternater to work with a battery isolator? Need a way for the alternator to sense the battery voltage.



I would like to know more about the 110-258 alternator.
1. What is the maximum speed(rpm) for the alternator?
2. How much is the lifelength reduced if you push the alternator to the rpm limit.
3. How much is the capacity reduced by temperature?

4860JB Dim warning light

Alternator: Aoo14860JB
Regulator: E103724

My dash Light now comes on Dim and stays that way after start up. The ignition wire has a pos. 12.6 volts.(at alternator)Voltage at battery isolator is 13.4 volts, with engine running.
I'm told this maybe a bad Diode? If so can you supply me with the correct part? Alternator is only one year old.(1,000 miles)


AVI 128 35215334UK


   need wiring diagram to connect to volvo penta md17c. thank you

                 regards ben

Alternator part number

I have an alternator on my bus, which is not original. It has a built in voltage regulator. The label on the VR states that it replaces a Leece Neville 79000. How can I find the alternator part number. I would like wiring diagrams, bulletins, etc. for the unit.

Re - Type A127-MT


A Prestolite Alternator Des No 47020067 Type A127 - MT 12 volt 70 Amp alternator is fitted to an engine on a narrowboat I am about to work on.

Could you confirm please if this is or is not an isolated return type, and point me in the direction of any information regarding this alternator.


Dave Wilson

External Voltage Regulation.

I have a new 90 amp Leece neville alternator. Model # is *MR2070TA. It supplies 660 amp hour "house" batteries on my boat. I have purchased a Xantrex XAR digital alternator regulator.
This regulator has a duplex plug (stator and field) Where do I make the required connections on the MR2070TA? I assume I disconnect the voltage regulator supplied.

Wire hook up

How to connect a 7000 alternator to a Ford Regulator ?

Overcharging 4890jb

Hello all,

I am having an overcharging problem with your 320 amp 4890jb model atlernator installed on a '05 model e-one typhoon firetruck. It came to us with the typical cooked battery odor and was showing ~18 volts at the batteries at idle. The regulator appeared to be the non adjustable diode trio variety. I replaced the batteries as well as the regulator hoping this would cure the problem.

I followed the troubleshooting instructions on the website and still have not come to a resolution. I did see a tsb on this website concerning the rectifier, but it looks like it already has the updated version. We have already ordered a new alternator, but i'd like to fix this one and put it on the shelf for possible future use.

Thanks for any and all help!