Disconnecting internal voltage regulator on Yanmar alternator

[svstrider]

I have a Yanmar 3 GM30F raw water cooled engine. Recently the OEM Hitachi alternator died. The PO had disconnected the internal regualtor so that he could use a 3 stage Xantrex external regulator. I bought a new Hitachi alternator from the Yanmar dealer. The local marine electrician says that the warranty would be voided if he opens the alternator and also that it is too complicated to disconnect the internal VReg. Apparently it was a simple matter to disconnect the internal reg in the older alternator bought in 2000.

Any suggestions or ideas. I guess I wait until the 12 month warranty is up before trying to disconnect the internal VR and reconnect the external VReg.

[Lake-Effect]

Before any mods,are you certain the Xantrex regulator is OK?

Will the warranty remain valid if the Yanmar dealer makes the mod? If not, take it up a level and ask a Yanmar factory rep if this would indeed void the warranty.
if you haven't yet installed the alternator, maybe now's the time to return it and consider a Balmar or similar alternator, already set up for external regulation.

Or... wait out some or all of the warranty, then do the mod.

[cwyckham]

If you take it to a local alternator shop, they'll do the mod for you. I wouldn't worry about the warranty, myself, but it's up to you.

[noelex 77]

The Yanmar Hitachi alternator is one of the more difficult ( but not impossible) to modify to external regulation.
A good solution is to use a Sterling alternator to battery charger. This requires no modification to the alternator and is a little more efficient than conventional external regulation. The cost is more, but the difference is not great.

BTW I believe these alternators can often be picked up quite cheaply on eBay etc often new or nearly new. Many mechanics recommend selling the alternator and installing a brand that can be more easily converted, so there is a bit of an oversupply resulting in low prices.

[Jentine]

Plus 1 for the alternator shop. It is not a difficult conversion and everything will fit just like the original.