Alternater Problems

[Amber]

Hi guys. My dads bighorn melted a charge relay. He bought a new one put it in and it burnt that one out to. He measured the voltage for the coil and it was up at 20 volts so come to the conclusion the something is wrong with the alternator. However just to make sure, he removed the charge relay in my 3.1 Mu and measured the voltage and it was 14.2 +/-. On reinstating it however, now the voltage gauge on the dash reads 12v when idleing and 14.5V +/- when revving. It never used to go above 12V let alone move up and down. I'm pretty sure from start up it used to take a second or two indicating zero, then a click and straight up to 12v. Now it slowly moves up the scale to 12 then to 14 when revving. Measuring straight off the battery with a multimeter confirms the dash gauge. It is charging at 14.25V. Should the dash gauge be indicating that high and fluctuating or is the gauge meant to be regulated to 12v as it has in the past. It is also just noticeable with the lights dimmer at 12v idle then 14.2v revving. Can removing the charge relay have stuffed something. How do you guys gauges etc read? Your help is much appreciated as this truck is practically new and I am so passionate about it. I spent a c--p load buying it and can't really afford to throw much more at it but it is my only vehicle.
Cheers
Amber

[geeves]

Sounds like you fixed somthing you didnt know was faulty. If it was realy only putting 12v to the battery it would of gone flat so I think your gauge was suspect More likly though youve only just taken notice of the gauge. 14.5 is correct for charging voltage. Charge relays normaly get killed by bad alternators and quite often the stator ends up burnt out result $700 for an alternator. Our local sparky did mine twice for 1.5 hours labour + bits (second time it was just a clean etc and screw up warrentee as it was brim full of mud) but some sparkys will tell you 3 hours or more Good luck with dads bighorn

[draganlada]

I have burnt 3 charge relays before I went to see auto-sparky who find out alternator was faulty(overcharging) and quoted around $500 au for new one.I've been driving for few weeks afterward without charging relay inserted,until my alternator died completly and didn't charge atall.At my local parts store I bought new 70 amps (old one was 50 amps) for $350 and it works fine ever since.

Cheers , Dragan

[Amber]

When I used to turn the ignition on, no voltage would show on the guage and a second or so after start you would hear a click like a relay and the fault lights would go out and the volt gauge would shoot up. Now the volt guage shows the battery voltage as soon as you turn the ignition on and drops down for the start. Then it makes it's way up to 12v when idling while recharging. The headlights vary in brightness in acordance with the voltage and the idicator makes the volt needle go up and down as well even when up at 14v and charged. Is there some other relay which controls the volt meter and holds it off till after the start. I have read other posts that mention theirs take a while to come on. Has anyone got a electrical scheme of the charging systems.

Amber

[DavidM]

Hi Amber,
After reading yours last night I checked my voltmeter today. When I switch on the ignition the gauge flicks up to 12v almost immediately. After starting it reads 14.5v at all engine speeds and under all electrical loads i.e. headlights full beam and two 100 watt spotlights plus heater on. The engine revs have no effect on the brightness of the headlights on my car and should not on yours. I think a visit to an auto electrician may be in order.

David.

[geeves]

headlights = 120 wats
spots =200
heater at least 40
ie 360 watts which = 30 amps at 12v
Alternator wont deliver this current till 1500rpm minimum even if it is the std 70 amp model so some variation in brightness is normal Both my bighorn and the company corola do it. A high capacity alternator or battery though would reduce this effect though to some degree.
When my alternator was replaced the new charge relay that was fitted needed a quick rev to make the light go out . I went back to the sparky 3 times but they were adament this was normal. Filling the new alternator with mud meant they had to take a closer look and after replacing the relay again (and rebuilding the alternator) all is as it should be. They still wouldnt acept that this relay was faulty I wonder whos car its in now

[Amber]

Yeah I used to give it a little rev or wait a second or so and the voltmeter would click on straight up to just over 12v after starting so maybe the relay was kinda like yours and maybe had a bad contact or something. May have fixed something by accident. But now the headlights dim up and down with the revs for 8 minutes or so until the battery has charged back up and even when fully charged the indicators vary the voltage meter. Maybe I better get it checked out but sounds like auto-sparkies vary in opinion too and I would prefer to know from people like you guys who actually know about this particular vehicle.

Dads bighorn indicates straight away like yours David but I haven't taken much notice of anything else as I don't drive it. I have a Mu though and don't know if the systems are the same or not. His 93 3.1Td intercooled bighorn has a different alternator to my 95 3.1td MU but looks like the same charge relay. Different volt meter too.

[Amber]

Got it checked out yesterday. All the guy did was turn on everything and stick a voltmeter on the battery. I had already done that. It is apparently ok. Dad got his bighorn alternator fixed only but not replaced as Autosure wouldn't replace it. 4 of the 6 diodes had gone so was only charging at about a third of its output. They replaced the seals and the diode pack. Don't know how much the job cost but dad had to pay the $250 excess plus $100 for seals and freight etc. So $300. Pretty stink really as he has only had the vehicle for 2 months and bought it from the car dealers with 60000kms on it and this $1000 insurance thing so he is feeling a bit disheartened with the whole thing. He is starting to prefer the 2.3 lt 89 Bighorn instead with high mileage. Cheers for all your responses.

Amber

[geeves]

Surely Autosure insurance would pick up everything except the ecess I would be complaining to them. also doesnt the 89 bighorn have the 2.8. All of these got much the same alternator and a new replacment would only of cost 500 +labout Mine was done about a year ago 700 all up. Dont you hate insurance companies.
As for whats normal This varies over a large range and is affected by many factors ie battery condition which is why I reconed yours was ok even though some other people came back with a nicer sounding result.

[Dave]

Autosure have a lot of small things that they won't cover (seals etc) but I would have a chat to the car dealer and mention that even though it has a mech. warranty, there should not have been a problem in such a short time period so they should reimburse you.
You would have a good chance of getting the money out of them if they refuse at first, just depends how far you want to take it (eg threaten MVDI or small claims action)


Dave

[Amber]

Do you reckon. I am not sure what the consumers guantee act says. Does any one know?

[Dave]

I have very bad luck with vehicles, and have been through this a number of times myself, with claims ranging from $800 up to $3000.

I would go to your dealer first, and see what they have to say about it. Even though it is a cat. D vehicle ie no warranty, it must be of "merchantable quality".
Most people would expect their alternator to last longer than a couple of months after purchase. The shorter the period from purchase, and the lower the k's the better.

If you are in any doubt check with the local C.A.B, or local community law centre for free advice. If you can save a couple of hundred $, it may be worth the phone call.


Dave

[geeves]

Im not sure an alternator failure would quite make the grade as far as whole car not merchantable quality. Its not in the same leaguge as no suspension or diffs held together with banana skins. I still belive its autosure that needs to pick up a larger part of the tab. A lot of dealers up here use autosure I think Ill be reading the fine and extra fine print before agreeing on the price of my next car.

[Dave]

Depends on who you deal with I guess. I have been reimbursed for the same thing but on a Surf, and I only had to pay $150 towards it (Protecta warranty), but kicked up a stink over it, and finally got money when they were contacted by the Small Claims Court.
I even took the vehicle back to have the stereo replaced because it didnt work properly, but only did this because of the original jerking around over the alternator.

[3vilc]

sounds like the relay in the MU may have been connected wrong? possibly backwards. never had a look at it so not sure if thats possible, but my bighorn has a circuit which only seems to be enabled once the engine is started. most of the extra electrics wont run just turning the key to on, the engine actually needs to be started, ie climate control/window heaters/headlight washers etc. that would cause the voltmeter to read 0 before start and 12 after if it was only reading from that circuit. strange though. but yes my voltmeter does indeed read 12 with key on 14ish after startup

[James W]

my bighorn has a circuit which only seems to be enabled once the engine is started

Well, thats what it is supposed to do, while the alternator is not working non essentials are cut out by the charge relay - thats it's job. Air-con, heater, etc won't work untill the alternator starts outputting. However the voltmeter should not be cutt out by the charge relay. Are you talking dash mounted voltmeter or a test meter?

[3vilc]

no my volt meter work fine, was merely pointing out that if Ambers voltmeter was connected to this circuit that would cause the 0v key on 12v engine running symptom.. but that was just my 2c worth

[mulover]

Heres a different question to do with alternators, i'm getting a 80 amp alternator to replace the 50 amp one that is filling up with oil from the pump on the back of it, do i need to put in different relays or diodes or anything like that??? Thanks for any advice.

[geeves]

As long as the connections are the same it should be fine. I found out today that you can buy the oil pumps separatly although I probably wasnt meant to see that page in the sparkys book It was still 250ish just for the pump though.

[mulover]

Thanks geeves, i'm getting this one off a guy on trademe, is supposed to be brand new and was only $300 including freght, i will post part numbers etc when its all working for anyone who is interested, so far all signs are looking good, just gotta wait for it to arrive!!!