Forums Migration

Please read this thread

Recent Topics
EP additive?
by CCI - 07/10/20 11:06 PM
Kawa FR600V Oil
by Propflux01 - 07/10/20 10:34 PM
Dexron VI for 700R4.
by jakewells - 07/10/20 10:22 PM
Picked Up the DeWalt Mid Range Impact
by Fringe - 07/10/20 09:42 PM
Checking out neighbours lawn mower
by Snagglefoot - 07/10/20 09:19 PM
TV help needed
by ffhdriver - 07/10/20 09:00 PM
FS Solar panels PU only 250w $80
by BeerCan - 07/10/20 08:29 PM
Ford Easy Fuel
by buck91 - 07/10/20 08:27 PM
Oil for the track
by lowon - 07/10/20 07:34 PM
Bought a grapple
by Ausfahrt - 07/10/20 06:30 PM
What is this charger for?
by CharlieJ - 07/10/20 05:58 PM
World War II movie Greyhound
by skyactiv - 07/10/20 05:48 PM
GC for Fuel Dilution - Accuracy
by Gene K - 07/10/20 05:21 PM
How Do I Get This On?
by Gebo - 07/10/20 05:08 PM
Creativity Suggestions?
by maverickfhs - 07/10/20 03:18 PM
3.5 Ecoboost Oil, I've decided.
by Gene K - 07/10/20 02:07 PM
Mopar Extended Warranty with 100% Refund Option
by The Critic - 07/10/20 12:46 PM
The great lakes are warm!
by OVERKILL - 07/10/20 11:38 AM
Newest Members
SUmeme22, DaveCaddell, SharkNC, Puckster02, TurbodogTodd
71907 Registered Users
Who's Online Now
62 registered members (bbhero, 92saturnsl2, ajchien, another Todd, BigCahuna, 4WD, 5 invisible), 1,326 guests, and 27 spiders.
Key: Admin, Global Mod, Mod
Forum Statistics
Forums67
Topics307,708
Posts5,316,177
Members71,907
Most Online4,538
Jan 20th, 2020
Donate to BITOG
Print Thread
Hop To
Page 1 of 2 1 2
Car is killing alternators #5210460 09/11/19 08:14 PM
Joined: Jan 2014
Posts: 530
S
Spetz Offline OP
OP Offline
S
Joined: Jan 2014
Posts: 530
Hi guys,

I have an old Mitsubishi Mirage that has had a Mitsubishi FTO motor transplanted into it.

It keeps going through alternators. Some only seem to last minutes...

Some points:
1. This is a car I use on the track so the power draw is low (essentials only, nothing else)
2. The alternators I have used have been 2nd hand units (yes, they are 20+ years old) however I have gone through about 6 of them so far with a total run time of 10 hours I would say on the car
3. The last time I had the car on, it was fine. I let it sit for 2 months and started it again and the alternator is dead (battery was flat too, left connected)
4. The battery I use is a Deka AGM which is underpowered for daily use.
Specs of battery:
Voltage: 12
CCA: 325
Capacity (Ah): 19


I have been researching what to do/test.
The first thing I plan on doing is checking for resistance between the positive and negative terminals of the car to see if there is a short somewhere
Check +-ive cabling
Check for good ground

What else can it be?
What else can I check?


2003 Mitsubishi Diamante 6G74. 165k miles.
Penrite HPR10 10W50, 12K km OCI
UOA:
https://www.bobistheoilguy.com/foru...ante-shu-5w40-1-2-can-mos2-7-8k-mile-oci
Re: Car is killing alternators [Re: Spetz] #5210477 09/11/19 08:45 PM
Joined: Jun 2012
Posts: 806
R
redbone3 Offline
Offline
R
Joined: Jun 2012
Posts: 806
The only time I have seen this problem is when the bonding cable between the chassis and engine was defective/


2014 Passat Wolfsburg, 1995 Miata.
Re: Car is killing alternators [Re: redbone3] #5210498 09/11/19 09:03 PM
Joined: Apr 2015
Posts: 840
M
Mainia Offline
Offline
M
Joined: Apr 2015
Posts: 840
Originally Posted by redbone3
The only time I have seen this problem is when the bonding cable between the chassis and engine was defective/


Even on a new car , I always add another chassis to engine connection and on new and old connections use ant-ox grease and coat the connection with Fluid Film.


2018 Lowered Hyundai Kona AWD 1.6T https://www.hyundaikonaforum.com/showcase/2018-kona-awd-1-6t-lowered.1162/
2014 Toyota Rav4 AWD
2005 Honda Civic
Re: Car is killing alternators [Re: Spetz] #5210511 09/11/19 09:25 PM
Joined: Sep 2015
Posts: 2,735
M
mk378 Offline
Offline
M
Joined: Sep 2015
Posts: 2,735
You've done all this with the same battery? Battery could have a short that overloads the alternator. Or it just doesn't hold charge and you think the alternator is bad.

Also there's a wire from the ignition circuit that powers up the alternator.

Re: Car is killing alternators [Re: Spetz] #5210527 09/11/19 09:53 PM
Joined: Jan 2014
Posts: 530
S
Spetz Offline OP
OP Offline
S
Joined: Jan 2014
Posts: 530
Yes, this is all done from the same battery.
The battery was bought new...
Also, when the car is running there is no output from the alternator.
It is just running on the battery power


2003 Mitsubishi Diamante 6G74. 165k miles.
Penrite HPR10 10W50, 12K km OCI
UOA:
https://www.bobistheoilguy.com/foru...ante-shu-5w40-1-2-can-mos2-7-8k-mile-oci
Re: Car is killing alternators [Re: Spetz] #5210553 09/11/19 10:33 PM
Joined: Jul 2005
Posts: 71
S
StarCaller Offline
Offline
S
Joined: Jul 2005
Posts: 71
there is one constant: the battery /
ask one of your buddies for a battery over the weekend & see what the outcome is /

on the other other hand, before you put a different battery in, you rather triple-check the alternator wiring /

Re: Car is killing alternators [Re: Spetz] #5210554 09/11/19 10:33 PM
Joined: Dec 2013
Posts: 4,646
C
clinebarger Offline
Offline
C
Joined: Dec 2013
Posts: 4,646
Resistance checks are absolutely useless on high amperage circuits!


2001 Chevy Camaro L92/4L80E
2006 Chevy 2500HD LBZ/Allison 1000
2010 Toyota Corolla 2ZR-FE/U341E
2000 Toyota Avalon 1MZ-FE/A541E
Re: Car is killing alternators [Re: Spetz] #5210556 09/11/19 10:38 PM
Joined: Oct 2011
Posts: 2,072
U
user52165 Online Content
Online Content
U
Joined: Oct 2011
Posts: 2,072
You say used on a track car.

What rpms are you running?

Last edited by user52165; 09/11/19 10:40 PM.
Re: Car is killing alternators [Re: Spetz] #5210575 09/11/19 11:08 PM
Joined: Jan 2014
Posts: 530
S
Spetz Offline OP
OP Offline
S
Joined: Jan 2014
Posts: 530
The engine runs at around 8,000rpm.
So it is pretty high, however this is the standard redline of the engine


2003 Mitsubishi Diamante 6G74. 165k miles.
Penrite HPR10 10W50, 12K km OCI
UOA:
https://www.bobistheoilguy.com/foru...ante-shu-5w40-1-2-can-mos2-7-8k-mile-oci
Re: Car is killing alternators [Re: Spetz] #5210585 09/12/19 12:11 AM
Joined: Oct 2011
Posts: 2,072
U
user52165 Online Content
Online Content
U
Joined: Oct 2011
Posts: 2,072
20 year old, second hand units. 8000 rpms......................hmmm.

We would need further info to calculate the alternator rpm.

Are these units spec'd for this engine?

Do you have perfect pulley alignment?

Is this a V belt or serpentine type?

Re: Car is killing alternators [Re: Spetz] #5210592 09/12/19 12:36 AM
Joined: Jan 2014
Posts: 530
S
Spetz Offline OP
OP Offline
S
Joined: Jan 2014
Posts: 530
Yes they are old units, however I have gone through many of them.
One of which was a freshly rebuilt unit which only lasted a few minutes.

It runs off of a V belt.
Pulleys etc are all new.

Yes the unit is for this particular engine. It won't be the rpm, it was all designed for this from factory.


2003 Mitsubishi Diamante 6G74. 165k miles.
Penrite HPR10 10W50, 12K km OCI
UOA:
https://www.bobistheoilguy.com/foru...ante-shu-5w40-1-2-can-mos2-7-8k-mile-oci
Re: Car is killing alternators [Re: Spetz] #5210601 09/12/19 01:12 AM
Joined: Sep 2009
Posts: 80
L
LvR Offline
Offline
L
Joined: Sep 2009
Posts: 80
If the alt has a built-in regulator then not much can go wrong electrically if its sound to start with.

You say you have an "old" vehicle ............... possible you have an external to the alternator regulator, that have funky connections on itself or bad cables running to the alternator?

Re: Car is killing alternators [Re: Spetz] #5210739 09/12/19 08:13 AM
Joined: Aug 2019
Posts: 47
B
benjayman227 Offline
Offline
B
Joined: Aug 2019
Posts: 47
Assuming you find the actual problem, an underdrive kit would be prudent. Your electrical needs are very different from a DD that cruises at 1500rpm around town with headlights, wipers, radio, and defogger all cranking, and the "factory" design parameters are set with that guy in mind.

Re: Car is killing alternators [Re: Spetz] #5210869 09/12/19 11:08 AM
Joined: Feb 2014
Posts: 3,945
L
Lolvoguy Online Shocked
Online Shocked
L
Joined: Feb 2014
Posts: 3,945
Originally Posted by Spetz
It won't be the rpm, it was all designed for this from factory.

You are not operating your vehicle at "factory" levels.
How can you expect to push stock parts to high performance levels?!
Surely more electrical upgrades would be required.


06 Lexus IS350- Wife
88 BMW 325is- Mistress
Say "no" to Turbo!
Re: Car is killing alternators [Re: Spetz] #5210880 09/12/19 11:24 AM
Joined: Jan 2015
Posts: 1,850
R
ragtoplvr Offline
Offline
R
Joined: Jan 2015
Posts: 1,850
1. Never use alternator to charge dead battery. Do you have a trickle charger . To recharge that battery you want C/10. C is,19 so charge should 1.9 amps. 2 OR 2.5 AMP trickle charger would be good. The alt can supply 40 amps to that battery which will severely shorten the life. When discharged the battery can not function as surge absorber and kill regulator.

2. Do you know what failed on the alt? Diodes, regulator?

Rod

Page 1 of 2 1 2
Previous Thread
Index
Next Thread

BOB IS THE OIL GUY® Powered by UBB.threads™