new alternator only charging at 11v

[jimbo_1122]

i have a 1997 escort 1800 zetec, the alternator was only charging at 11v, measured across the battery. i bought a re-con alternator which was bench tested at the breakers yard i bought it from and was putting out 13v.After i fitted this and tested it i only had 11v again, measured across the battery and direct on the alternator terminals. i have cleaned the spade connectors going to the alternator, the battery terminals and the earth strap comin off the battery. still only 11v. why did they get a reading of 13v when i only get 11v?
please help

 

[moderator]

its your battery.

when your alternator has no load you get 13v, give it a load and it drops

it coulld also be you battery is on its way

 

[Steve]

its your battery.

when your alternator has no load you get 13v, give it a load and it drops

it coulld also be you battery is on its way

this IS a first

moderators giving advice?

 

[jimbo_1122]

it should be 13-14v with a load. does this mean it should bench test higher than 13-14v?

 

[jimbo_1122]

have tried a battery that i know works, made no difference. have tried running a seperate earth from the w connection on the alternator, made no difference. anyone have any ideas, i'm really stuck.

 

[Belle427]

is the belt drive tight enough?

 

[keyplayer]

Maybe you need a new voltmeter?

 

[Spark123]

Looking at my diagram you should only have two positive wires connected to the alternator, the indication connects to D+ and the battery to B+ via the starter motor. You'll also have maybe a couple of earth wires on there somewhere. I am led to believe it is not a good idea to run alternators open circuit as it can cause them to fault, you say you are only getting 11v across the battery? I'd expect somewhere around 13.5v after a minute or so. 13v is a bit on the low side too, you'll probably find you've been sold a dud alternator.

 

[keyplayer]

Edited

 

[jonnyfishing]

Just double checked(Autodata)and the output should be13.5v and 14v,any lower and your alternator is on its way.I think you have a duff alternator or faulty voltmeter....put a fully charged battery on and take it for a free test at a motorist shop to cross check them both.

 

[Spark123]

Where abouts on autodata did you find this info, I had a quick look but couldn't see. Got wiring diagram from TIS

 

[eggplant]

Was 13.5V in my day too, thankfully I dont work on filthy, smelly,dirty machines any more

 

[jonnyfishing]

Spark.

Info from "cd 2" 2004.

 

[Spark123]

Yup, I have the same one too!!