I noticed yesterday that my starter was sounding like the battery was low. When I went out this morning it was similar, but it did start. Once it was running I took a look at my volt meter and it was around 11.2, which is obviously low. I have an aftermarket gauge in my cig lighter position. When running I'm usually around 13.8 so I know I have an issue. I plan on checking belt tension and battery/alternator connections this evening, but is there anything else I should look at? Specifically because there was no light on the dash indicating a charging issue. I'd have been out of luck if I didn't install the additional voltage gauge. I have to imagine if it was working properly a light would have gone on being at 11v, but I'm not sure about that. Thanks,

 

Looking at other threads the voltage regulator may be playing a role. Is there a way to test that? It seems that that may account for the no light indicator.

 

After poking around and figuring out the regulator is internal, I’m confident I just need a new alternator. But I still have a question if anyone is willing. Looks like the air pump or sway bar will need to be removed, at least partially for the bar, to replacing the alternator. I do not use AC, hasn’t worked since I purchased the car. I also have no smog requirements in my state, amazingly. Can I just remove the air pump permanently? I’m pretty sure that belt only turns the AC compressor. I’ve looked into the air pump removal in the past, and it’s not worth buying the adapter bracket. But if I don’t care about AC, is there anything stopping me just leaving it out?

 

No harm in removing air pump as long as belt rerouting won't be an issue which you seemed to address. You may find the check valves into exh manifolds at rear of motor are rusted out anyway, they usually are.

You can leave the AC comp off also, just plug the AC lines with good rubber stoppers and secure the stoppers so they can't come out. The cruise control bellows in behind the AC comp, but i can't tell you if it attached in anyway, or not. They may share the same bracket

Doug

 

Alternator light,

Turn ON the Ign, NO START, and observe the light is ON. If so, then alternator is suspect.
If NO, then replace the bulb, try again. That alternator exciter system is "special", and the Lucas sticker makes it more so. The alternator "should" self excite at about 2000 engine RPM, some do, some dont, refer to that Luca sticker again.

The alternator comes out the top, NOT the bottom.

Removing the air pump and the associated junk is good. There was a Jag Idler arrm assembly for no air pump markets, but that was eons ago, and finding one now, good luck. NOT impossible, just not off the shelf anywhere.

While ypuir ;looking, pay SPECIAL attention to the engine Earth strap at the LH engine mount and subframe area.

 

It was a good feeling getting the air pump and compressor out. I gave the bay a good clean after and there’s definitely more accessibility with those items out. I was kinda shocked how heavy the compressor was. The new alternator is in, but it seems that it doesn’t charge on initial start up. Once I drive or let it idle for a bit it gets up to 14v, but from memory I don’t think that was always the case. Maybe I need to check the belt tension, but I read above it may need to get up to 2k rpms to excite charging, but it will eventually charge even at idle.

 

Have you checked your battery terminals and battery water levels?
Two of the easiest things to check and by far two of the most common things overlooked.
Make sure both terminals are free of corrosion, fully seated and tight enough to not spin on the posts.
Water levels should ALWAYS be above ALL the plates.
Check ALL the cells.

 

Your year car possible/more than likely, had a Load Dump Module attached to Alternator.

I have Never seen one, only been involved with the Black Beast in Manila many years ago.

His was mounted on the chassis, and a lead attached it to the alternator.
He had similar issues, and once disconnecting that unit, all was what we say is "normal".

 

Shouldn't have to wait that long nor rev to 2000 to start the charging process.

Is the dashboard warning light still non-functioning? If it doesn't work that might be a clue. The resistance from the warning light is what "excites" the alternator....although you'd think the resistor wired in parallel with the bulb [see diagram] would do the same thing.

Your car should have the dump module that grant mentioned. I never learned how those actually operate.

Cheers
DD

 

Another possibility is a slipping harmonic balancer, usually happens when cold then hooks up after a few minutes....
Put some white-out in a line in the pulley and hub, if the line separates into two over time, your balancer is slipping

 

Thank fellas, all good suggestions. Just getting back to being able to work on things, so I'll go through some of the items tonight. The battery leads are very new as well as the battery, so I can rule that out. I agree though, many times on other vehicles it has been just that simple. I've considered the harmonic balancer and will try the suggested test. That would make sense if it was slipping. I do get the indicator light in the on position, but once running it still turns off (even when it's "warming up" and at 12v or lower). I would think that should be on until I'm up near 13v. There is a small box/cover where the two thin gauge alternator leads pass through on the interior passenger wheel well. I can get a pic later. It looks to have two screws keeping it attached to the well. I'm not sure if that's the load dump module, but is where the two smaller leads make a stop before going into a loom up near the top (I'm guessing there is some sort of junction in there, if not the module)

 

So I did find an example of the load dump and it is what I am seeing on the wheel well. Any reason to not bypass it? Looks like one wire goes to a ground and the other to the alt. I thought it was both wires from the alt going into it, but it's hard to see in there, so I'm thinking the other must go the gauge and not that box.

 

I would NEVER assume the leads are seated and tight or that the fluid levels are topped up.
These are easy things to check and should even be regularly inspected, EVEN with a new battery, just like when checking your oil.
Do you do your own oil changes?
If you do, do you check for leaks and correct oil level?
Do you have your oil changed at a shop?
Do you check their work afterwards?
If you don't check you are just asking for trouble.

 

I would NEVER assume the leads are seated and tight or that the fluid levels are topped up.
These are easy things to check and should even be regularly inspected, EVEN with a new battery, just like when checking your oil.
Do you do your own oil changes?
If you do, do you check for leaks and correct oil level?
Do you have your oil changed at a shop?
Do you check their work afterwards?
If you don't check you are just asking for trouble.

 

That load ump is "supposed to" dump excess voltage to earth, whoopee, another electronic thing to mess with the humans.

Unplug the wire AT the alternator, BATTERY DISCONNECTED of course, then remove the earth screw, and the box itself, bin it.

The theory was good when it was new, its not new anymore.

 

Just disconnecting the ground from the load dump module fixed the issue. Immediately gets to 14v. Next time I’m down in there I’ll remove the whole thing. Thanks everybody, never would have guessed that. At least I have a new alt, not even sure if the old one was bad, but I got much more familiar with that area and also removed some weight.

 

SIMPLE CARS THESE V12's.

Well done.

Beers on you mate.