Low voltage?

[indybaird]

When I bought my M37 the volt meter (ampmeter?) was reading in the yellow on the way home. I checked the voltage with the engine running and got 27.5 V, I charged the batteries and checked them with my load cell and they showed weak so I replaced them and still and reading in the lower part of yellow. Any idea where I should look?

[Carter]

I believe your charging system is not working, check the battery connections esp ground connections, after that a set like Bill L has for sale is needed to access the system and make further tests.
viewtopic.php?f=2&t=4922

[indybaird]

I'll break all the connection points and clean. As I noted it's putting 27.5 V to the batteries checked with a voltmeter at the batteries when it's running, checked voltage when off at a little over 25 V after a 25 mile drive and sitting overnight. I looked at the operator's TM online and I thought between 27 & 28 was good. Will watch for one of those kits for sure, thanks.

[Carter]

25V after driving and sitting overnight is just in the fair range, the batterys should have built up some charge after sitting all night, try disconnecting the ground next time and see if the voltage increases to something above 25V after 12 hours or so.

[indybaird]

Great idea, looking for a drain. I hadn't thought of that. The batteries I have in it are rated at 530 amps@32" and 425 cold amps. They were the best fit the local box auto parts store had and at $100 @ that I wanted to spend on tires I hope thats not the issue. Are these big enough the to make the system happy?

[k8icu]

The voltage regulator may need adjusting, but I have no clue how to do it. All my MVs in the past either had the Altinator or the electronic regulator. Most M37s unless it was replaced have the older relay type regulator and as I understand it there is a fine art to adjusting them. A good system should be putting out 28.5 volts.

[indybaird]

after a short drive this afternoon the voltmeter got up to the lower side of green, maybe the new batteries were a little low but sure want to see it up into the deep green.

[Carter]

Are these big enough the to make the system happy?

They should do fine, what kind of regulator do you have,the adjustable relay type with a bread box shaped cover or solid state with a flat cover?
Solid state, click on pic


Try charging each battery separately, overnight, disconnected from everything but the charger, reconnect and see what voltage you have then take a drive and see what voltage you have then.

[indybaird]

I've got the solid state reg.

[indybaird]

After the barreries charged up the meter is happy and so am I.