90 amp Alternator upgrade?

[Cruz]

Is it worth upgrading to one?

Currently my alternator peaks at 13.5v but with headlights on and intermittent wipes it just makes it just over 13v. (brush pack 2.5 years old)

I'm soon to be fitting a propex so would a 90amp alternator give thye leisure battery more charge for running it?

I'm assuming I've got a standard 65amp alternator on at the moment

[billy739]

as long as the brush pack isant faulty!

it should still push 14.8v at at least 2000rpm

[Cruz]

My alternator pushes out nowhere near 14.8v.

About 13.5 for the first 30 minutes then up to 13.9. This is measured at the battery

[billy739]

try it at the back of the alternator, make sure theres no wiring faults.

[kevtherev]

Cruz
you could upgrade yes.. I did but changed back.
Your propex will be dependant on a good battery not a good alt
thing is going to higher amp alts only helps with discharged batts. It will charge it up a bit quicker and still have plenty of power for lights and heater blowers etc.
If you really want battery peace then traction batts are the way forward.
I'll be fitting one this year I think as like you I have a propex and get a bit worried at the end of three nights, these batteries would last three weeks before things happened

[eatcustard]

as long as the brush pack isant faulty!

it should still push 14.8v at at least 2000rpm

At engine idle the voltage should be between 13.6 to 14.3 volts

14.8 is that a tad high?

Mine is 13.85v at idle (90 Amp alternator) and does not go above 13.9 at any rev range

[ninja.turtle007]

Mine is 13.85v at idle (90 Amp alternator) and does not go above 13.9 at any rev range

Same here.

[Cruz]

Mine usually starts off at 13.4 and then rises to 13.8 after a right good run. However with the lights on and wipers going in the winter it's down to 12.8

[ninja.turtle007]

As said bbt Billy, check the V at back of alternator then at both batteries to see if you are getting a drop.

Mine was inconsistent, turned out the main cable from alt to battery was breaking down and needed replacing.

[Cruz]

Where would I check it at the alternator? The wires come from the atlernator via a push in plastic plug

[ninja.turtle007]

Push a probe of you multimeter through the insulation of the thick cable earth the other probe.

[billy739]

or have a look at the plug , the uper bit should clip open to show the rear of the terminals


if you buy a 90amp try and get the wiring loom , or some good connectors and heatshrink as the connections are different.

[Cruz]

13.9v at the alternator

[ninja.turtle007]

13.9v at the alternator

Did you then check at both batteries?

[Cruz]

13.5v at the batteries