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General Information => General => Topic started by: parkdog on January 29, 2010, 10:25:33 am
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first off i have a brande new battery and glow plugs in just a month ago but lately my battery doesnt seem to have enough power to turn the engine over once then dies but it turns on the lights and stuff i even tried new connectors on my battery. could the battery be too small maybe? any help is appreciated.
i forgot to mention when i boost it it will start right away the battery light wont come on while im driving it either and the battery was similiar to the old one i had just alittle shorter in length.
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It's probly too small, if its smaller than what you had ?
You want at least 800 cc model
Maybe a Optima red top, and a 90amp alt.
I will locate to a 900 and make a battery box s/s to locate under my caddy truck bed
Gee-Bee
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There are three components to the starting system:
- battery
- starter
- alternator
All three of these (and the wiring inbetween) need to work properly...so my recommendation would be to test all three (or have them tested) before buying any more parts.
If it starts fine when boosted your starter is probably just fine.
If you've just replaced the battery there's a good chance it's fine.
So, I'd start by testing the alternator. If you have access to a multimeter (even a 4 dollar one from Canadian Tire) you can do your own tests:
- does the red "battery" light on the dash come on when the key is turned to "on"? If not, the alternator is not receiving the voltage it needs to start charging. Look for a broken/disconnected wire at the back of the alternator.
- with the engine off you should measure around 12.5V at the two battery posts
- when you start the engine and blip the throttle once the voltage should climb to something in the 13.5V-14.5V range. If it doesn't climb the alternator is not doing its job. Probable causes include broken wires/corroded connectors at the back of the alternator, loose alternator belt, or a defect inside the alternator (brushes, regulator, diodes).
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yeah my bad the cca is only 590 the wiring is pretty hagard but not corroded really bad. so i guess ill try a new battery.
edit i looked at the ca and not the cca so yeah its 590 not 739
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I run a 650 CCA battery and it cranks the car over just fine, even at -20 (coldest so far)
http://www.vwdiesel.net/forum/index.php?topic=22321.0 (http://www.vwdiesel.net/forum/index.php?topic=22321.0)
I think you will find your problem if you follow the proceedure in that link.
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the cca is only 738
More than enough... the size of your battery is very likely *not* the issue here.
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the cca is only 738
More than enough... the size of your battery is very likely *not* the issue here.
X2
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Battery volt check, Alternator output check, sounds like your taking more from the system than your charging ?
I never replace one without the other, the stock wiring from the alternator is crap, I had a custom one made for my install...
G.B.
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I had a custom one made for my install...
G.B.
Course you had one custom made from 24k gold plated wire :P GB! You wanna send some moulah my way ;)
I have two big batteries I salvaged from a 6.9 ford i was scrapping.. I can crank the engine with the gp's on all day long. There is totally enough room up front for two batteries.
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i still think he has a ground issue probably. my rabbit used to be SOOOOOOO picky about grounds. if it was a little dirty, it wouldnt crank. then you had to clean it and it would fire right up.
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i will try and clean the ground and see if that helps. im thinking you might be right and im guessing putting new wiring would be farely cheap could i buy all the connectios at the hardware store and just make my own wiring?
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http://www.vwdiesel.net/forum/index.php?topic=22321.0 (http://www.vwdiesel.net/forum/index.php?topic=22321.0)
Did you try this?
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not yet i dont have a multimeter and i live in a small town right now where i dont know anyone. and im guessing replacing the wiring woulr be a good idea anyway way just to be safe. ill see if the hardware store here has a multimeter if not ill have to wait till i go to the city next.
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That test will tell you what you need to replace and what you don't. It'll save you money (most likely)
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so the hardware store doesnt have a multimeter in stock :-[ so i decided to sand the grounds down. good news is it started instantly :) now im a happy boy but ill probably still rewire my car for the most part. i just use it for a winter car but im contemplating doing a build this summer when the funds are more readily available. thanks for all the suggestions.
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haha, i knew it was gonna be your grounds 8)
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haha my hat goes off to you sir. but i kinda think my battery could be upgraded to a bigger one when i start it in the -15 or lower it has alittle trouble starting but will start. the battery is 738ca and 590cca
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all my batteries in my diesels are 1000ca or bigger, at least 800 or so cca. always spins mine up just fine.
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Ah (Ampere-Hours) tells you how much power a battery will store. The current multiplied by time in hours gives you the Ampere-Hours (Ah). So a current of 1 (one) amp for 1 (one) hour would be one Ah (Amp-Hour).
Batteries that are utilized for Gasoline engines like SLI (Starting-Lighting-Ignition) batteries are not rated in AH but rather in the CCA (cold-cranking amps), due to the fact that they are designed only for use in starting the engine, once the engine has started they should not be used.
The reasoning is that deeply discharging this type of battery will Greatly reduce its life. Also it will have statements such as 5 hour rate or 15 hour rate, this means that the battery will discharge perpetually over 5 or 15 hours, and the AH (amp-hour) capacity is a measurement of how much it puts out before reaching 100% DOD (Depth of Discharge). The DOD is how much of the available charge is used compared to 100% (or 1.75 volts per cell, or 7.2 volts for 12 volt battery).
The RC (Reserve Capacity) is generally used on deep cycle batteries. The RC is the number of Minutes a battery can manage a useful voltage (1.75 volts per cell). When using a system with heavy load requirements the Reserve Capacity (RC) is a more useful measurement. AH equals RCx.60 (Minutes vs. Hours)
MCA (marine cranking amps) basically is the same as CA (cranking amps) which is the measurment of how many amps the battery will put out for 30 seconds at 32 degrees F, before the voltage drops below 1.2 volts Per Cell. The CCA (Cold Cranking Amps) of a battery is much more important at cold temperatures because the CCA is measured at Zero (0) degrees F, versus 32 degrees F for MCA and CA.
I think proper diesel batteries are measured in Ah as to how much power can be taken from the battery for the first however, instead of being able to provide a big spike of energy for starting.. you know?
To run the gp's, and then the big draw of a diesel starter.
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I'm getting in this late but just wanted to add a couple comments from what I have noticed and recent battery problems I have had.
With diesels there is a big difference between starting and cranking.
If your car doesn't start, put the battery on a charger overnight. If it fires up then the battery may be OK. The next test would be to charge it and let it sit overnight and then see if it will start. If it does, I would suspect that your charging system is not up to par.
What happened to me is that my battery would crank the engine for 1-2 minutes without starting. It would gradually slow down to the point where I would recognize it wouldn't fire and I had to get a boost. It didn't happen 100% of the time, and there was no direct correlation to ambient temperatures. Sometimes it would fire on a cold day, sometimes it was really slow on a warmer day. The way things were going, I suspected my glowplugs. Last Friday it finally got to the point that I had to call CAA for a boost to get home. I replaced my battery, and it fired within a few revolutions. Sat over the weekend, fired up instantly this morning. White smoke to beat all, so I may still have glow plug issues, but.....
A co-worker had a battery that wouldn't start his diesel any longer. He took it out and put it in a gasser. 6 years later it still fires up the gasser every time.
Most battery load testers are scaled for gasser requirements. The battery I pulled out of my car tested marginal but OK but it won't fire up my diesel. I suspect either internal circuit problems in the battery or it's just too worn down for a diesel.
It's amazing how much difference a good battery will make for starting.
BTW, if you get a boost and it fires right up, that is the difference between a good battery and an inadequate one, even if it does crank the engine.
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yeah its been starting everyday now since i sanded/cleaned the grounds now to get my tach to work it will work once in a while could this also be from a battery/connection problem i noticed one day i moved the connections around on the positive side of the battery and the tach worked all day long then the next day it just went back to how it sits over the red line. like it bottoms out or whatever.
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might be a funky w signal from the alt...
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I just check my 100 Ah battery by puting load of 5 A (1/20 part) and till the min recomended 10.8 V it`s take 4.5 hour so my bat is 22 Ah ONLY.So by book I shall put 1 A (1/100) till 15 V when again to drop till 10.8 v I am interesting to see will it last,today`s battery last max 4 winter on short distance mainly.Your exprience?