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TAKEUCHI TB016 not charging

proplan2 ยท 2025-01-11 04:27

Hi guys, I appreciate any help with my Takeuchi. The battery is not charging. I have already done to alternator replacement, but still no charge while the engine is running. Specs: Takeuchi TB016 year 2005 with Yanmar 3TNE68 engine. Alternator is the "dynamo type" (the slim one) According to the workshop manual should make about 25V AC directly measured on the alternator, while engine is runnig - it does. But on the dashboard still blinking the charging light and if I measure the battery, still the same voltage while engine is running or not (about 12V DC). I know, that somewhere should be a regulator, but no luck to find it. Does anybody knows the location of the regulator? Or some other ideas, what should make this problem with no charging? Thanks for any answer PS: Images with the alternator type and the main relays in the battery area etc. attached.

Replies5
  1. #1Simon C2025-01-11 15:13

    Need to check your cables from the alternator going to some kind of rectifier I presume. Because 25 AC does not charge a battery, has to be rectified to DC power. Are all the battery connections good. Battery cables good, ground cables good. No plug in is loose or fallen apart. You said you already change out the alternator, so my guess is a wiring or control problem. Be nice to see a schematic on it. Simon C

  2. #20072025-01-11 18:11

    Can not be to hard to find as has those two thicker blue wires going into it. They often have a plug in the wiring at the regulator as they are a throw away item. So the colors of the wires may change at the last moment but the size of the wires will still be thicker like at the alternator. Often have aluminum finned case and are potted with epoxy so you cannot service. That type of alternator does not produce much current so the regulators can be quite small. I have seen them sometimes in the air intake of the engine to keep them cool. They are normally reliable and most times stop working because they loose there earth reference and stop allowing charge current through to the battery. They often have a inline fuse in the battery wire right at the regulator and that fuse can fail also because of heat cycling.

  3. #3Simon C2025-01-11 22:01

    007 Glad you have worked on this odd ball wiring system. I am sure that if he checks that fuse and everything else you have mentioned, the problem will be apparent. Good of you to point the member in the right direction. Simon C

  4. #4Glen Petherick2025-04-26 02:36

    Oops, I just asked the exact same question for the exact same fault on my TB016.... Does anyone know if this got solved?

  5. #5Glen Petherick2025-04-26 03:35

    Found it! Under the main body on the RHS, in a cavity towards the front of the exhaust pipe bolted to the wall.