Alternator fix or upgrade??

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Hi all,

I have to admit to being a bit of an interloper on this forum, as like some others, I have a Landy which is sporting a 2.8 TD under the bonnet

Since I've had my Landy, I've upgraded some of the lighting added some more, and then added som more on top of that too. I'm also thinking of doing some other bits 'n' bobs which will increase the electrical loading.

In view of this I've been having a poke around the alternator area, and have discovered a few things. Firstly It seems to only output 13.2 volts at the battery, and 13.8v at the pole on the alternator. At where I guess 1300 rpm to be it is apparrently kicking out about 10 amps, which I've read is about right.

So why is the output voltage so low? I know it's within spec, but only just, and I'd like it to work better than it does. I guess I may need to replace the brushes and clean the contacts but is that likely to fix the problem (I don't know very much about alternators - in fact there's quite a lot of things I don't know too much about Lol

I assumed the VR was internal to the alternator, but I've also read that this is external - is that the black block that's on my inner wing? it's a couple of inches square and I think the wiring plug from the alternator may end up going into it.

Is it worth servicing the alternator or should I just upgrade to a higher output model, and what have others used in place of the OE one?

Sorry for so many questions, but I'd really appreciate any answers - especially keen to hear about upgrades

Thanks
Andy

Think a good service would

Think a good service would be a good idea. New brushes are very cheep. The black box you've mentioned does sound about right for the regulater. These go wronge more offten than the aulternator themselves, but that tends to result in the aultinator pumping out way too much juice all the time, and cooking your battery.
I would sugest that your battery may be at falt. Or when did you check the voltage? Was is straight after starting engine? Try again after a run out.

Any veiws expresed in this thread by me are purely from my own experience, and (sometimes) falible memory. Hope my comments help, but please don't take them as gospel.

Any veiws expresed in this thread by me are purely from my own experience, and (sometimes) falible memory. Hope my comments help, but please don't take them as gospel.

Thanks for the advice! The

Thanks for the advice!

The battery is new (the old one was abused whilst I replaced the water pump, then got distracted and rewired part of the engine bay, got distracted again and put everything through relays, got distracted once more and fitted an electric radiator fan)

I must admit that the measurements were taken shortly after starting, so I will take your advice and measure it after a trip to work (about 50 miles of high revving driving). I've certainly had no problems with a flat battery, so it must be up to the job for the moment at least, I just worry what my future plans will do to it!!!

Not having much luck on the

Not having much luck on the finding a bigger alternator front, so I looked at it sideways and have come up with anoter plan. How about a second alternator? As I intend to run a second battery anyway, I can hook up a second charge light in the cab, the crank has a second pulley doing nothing, so I could find a space for another alternator, get some brackets made up and then choose a meaty alternator as I see fit. It gets round the problem of the vacuum pump on the original alternator because it's still there, and if I cannect the two batteries via a kill switch, I could jump start myself if the main battery dies. I envisage all the high drain items coming off the second battery, which means a bit of rewiring, but I don't mind that.

Good idea or not?

Andy

Sounds doable. If your

Sounds doable. If your going for the 'kill swithch', how about a proper starter conection to both with a boat / race car type (big red plastic key usually) heavy breaker switch on both. As long as only one is switched on at any time, either will start her up. Or is that what you meant?

Any veiws expresed in this thread by me are purely from my own experience, and (sometimes) falible memory. Hope my comments help, but please don't take them as gospel.

Any veiws expresed in this thread by me are purely from my own experience, and (sometimes) falible memory. Hope my comments help, but please don't take them as gospel.

A second alt sounds like a

A second alt sounds like a much better idea. Messing around the the vacuum wasn't going to be a easy job.

So long as you make sure the new alt is aligned properly with the pully, you should have no trouble Smile

Good luck! Keep is informed of your progress Wink

VR

i had problems with the electrics, dimming lights at low revs, fuel drain and battery light on, slow windows etc. changed the voltage regulator and it fixed the lot. cost me a fiver!!

why not just fit a second

why not just fit a second battery in parallel with the existing one...the existing alternator will fully charge both batteries, you may find the extra battery capacity is enough to run youre gizmos if they arnt all on for too long.

If the battery is fully

If the battery is fully charged, or highly charged, it will reduce the output from the alternator as the battery does not require such charge.

If you are uprating the lights substantially i would suggest a higher rated alternator conversion, and if finances permit, a marine alternator as these are waterproof. Landie headlights are like candles in brown paper bags anyway so simply uprating them would not require an alternator replacement. If many additional high output lights such as 4 X 100watt lights are being added, replace the alternator if they are to be used for longer periods.

The battery will be nearly

The battery will be nearly fully charged - just topping up from starting will be all that is replenished. I thought though that the current would reduce rather than the voltage?

I agree with the headlamp comment - I've already sorted that, and the 4 x 100w spots are already there! My next toys will most likely be a second battery on a split charge realy, a winch, and an electric heater for a tank of veggie oil (my next major project will be a twin tank conversion).

Do you have any experience of swapping out the alternator? I have no idea where to start looking for anything that might fit, and the internet has by and large failed me on this one. Ideally I'd like to bring it up to something in the region of twice it's current output - maybe 90Amps - more if possible. I'm working on the assumption that bigger is going to be better. Given the price of a replacement Fourtrak alternator, money has to be no object!!!

Yes, current goes down,

Yes, current goes down, voltage goes up (though not too much as long as regulator is working properly) as battery recharges.

Any veiws expresed in this thread by me are purely from my own experience, and (sometimes) falible memory. Hope my comments help, but please don't take them as gospel.

Any veiws expresed in this thread by me are purely from my own experience, and (sometimes) falible memory. Hope my comments help, but please don't take them as gospel.