Ever since I bought this Land Rover (3 mo ago),I've been trying to resolve an intermittent charging issue that was confounding me.I first noticed it on the way back from CA when we got stranded in Montrose, CO with a dead battery. It would charge fine but quit charging when too many accessories were turned on. Then resume charging when ya turned enough accessories to get under a certain amp drawthreshold. The tach would also quit when the charging stopped.

An autozone on-vehicle test showed a bad diode in the alternator. I had it tested at two different Autozones and it read the same way. When I got home I replaced the diodes (rectifier pack) and the brushes/regulator with new. They were worn about 1/2 way. Didn't make any difference, still acted the same way. The alt shop guy I know suggested a different regulator.Even after the new regulator, brushes assembly, it would notcarry a charge underincreased amp load. I had it tested off-vehicle at a couple different places. Some of these parts stores machines indicated it passed, some said it passed but only marginally. Thing is most of these guysat the parts store really did'tknow how to interpret the results much beyond "pass/fail" that the machine indicated. The guy at Napa tested it and said it was charging, but not much under load ...but as I pressed him for details, he conceded his machine didn't have a Land Rover test and he tested it as he would most alternators (which probably didn't make any difference). I was reluctant to replace it because I didn't have the sense the alternator was really bad. Finally, yesterday I took it to the best alternator place in town. They charge $5 to test an alternator (typically), or it's free if they rebuild it. I held off going there because last time I went there they gave me flack for rebuilding my alt, like I couldn't handle it, blah, blah, blah. I've rebuilt many over the yrs, never had one NOT work afterwards. The guy was extremely thorough. Had an oscilloscopehooked up to it as he tested it and did a whole battery of tests right there in front of me. He ran it to 100 amps for a lengthy period,it even put out 120A...even though it's a 100A alternator. He said, "This baby's in great shape!". We talked about it,he listenedand he suggested that my symptoms seemed consistant with belt slippage. I was really thrilled to get some good info, finally. Ultimately he didn't charge me and didn't want my money even when I volunteered to donate to his donut fund. To make a long story short, I checked it out with a routing schedule on the internet and sure enough, the beltWAS routed incorrectly, meaning, there wasn't enough belt contact (friction) on the alternator pulley. I bought a new belt for good measure, put it all together, the RIGHT wayand sure enough it works great! It's probably been like this quite a while because someone was working on the dash cluster (the tach would drop when it quit charging). They probably thought it had a bad tach.

Long story,I just wanted to share this story for others. My mistake was once I got the Autozone bad-diode diagnosis I boxed myself into thinking it was an electrical issue and failed to considerother options like a slipping belt.The other thing is, it would have been nice if Land Rover had a belt routing diagram on the vehicle (like most do), or at least in the owners manual. I have some alternator parts if anyone is interested.

 

Glad you figured it out. I knew that belt slippage could cause charging problems, but I didn't think that it actually ever happened and I probably would not have thought about it either.

 

My '97 has the a belt routing sticker under the hood. It is cracked and old so yours probaly fell off.

 

does anyone have this diagram you speak of ?

i have 95 3.9

 

I have a print-off of the diagram somewhere, lol, I think it's in my glovebox. Found it online, clock some google time and you should come across it.