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Discussion Starter · #1 ·
Right,Some of you are going to think I'm cheeky now, but what the hell its christmas and I'm going to go ahead anyway, besides it's a testimony to all you helpful souls, and an indicment on the rest of the internet car community that I've had to revert back to the old faithful. The car in question is a 1.7 TD Cavalier '93(don't ask!) on leaving the interior lights on, I flattened the battery so it wouldn't start, so I charged the battery checked the voltage (12.5 all good) and placed back in, still no start. hmmmm took the 75 amp virtually new battery out of my missus's griffin and tried that.....still won't start just a lazy sounding starter motor as if the batteries flat.The cav manual says a 60 amp battery should be used, well the one in it (and its been in since I had the car 12 months ago...and had no problems) is a 40 amp the starter motor I replaced march this year at a cost of £250 but the place that I brought it from is now 100 miles from where I live now! Point is....should a 75 amp battery start a 60amp required car (common sense says it should) Should a starter pack up 9 months into its life 4 of those where it was off the road so really 5 months of use. How do I test the starter (I can use a multimter only basically, so anything to do with using one has to be lehmans terms I'm afraid!)


Sorry for hogging the site with my inferior Cav pains/moans but I can't afford a 9-3 diesel and the petrol costs are horrendous with the miles I do. Thanks again.
 

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Some comments..
1) First of all I thought you say Cavalier.. but maybe I need my eyesight tested! )

2) A Diesel takes alot of ummph (current!) on a cold winter morning, which is when battery weeknesses are found out, especially on a Diesel.

3) Simply measuring the battery voltage car be misleading, especially bearing in mind point 2). The best test is a battery 'heavy-current' tester, but I have had weak batteries pass this test, and still be insufficient to turn over a Diesel engine!

4) But as you have used a known good(?) 75AMP battery, this should be ample to start the Diesel if the problem was the original battery!

5) So, as long as you are sure that the 75AMP Battery is good (and it sounds like it is), you have a seperate problem - and maybe the starter is a dud - although somewhat of a coincidence since all worked well until the battery was discharged!

6) Some starters can fail to engage properly, and a not too heavy tap with a heavy implement sometimes frees them up.. you could try this.
 

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Some ideas....

Check the battery voltage (measure directly accross the terminals, not the clamps etc)when cranking the engine. If it is greater than about 9V then your battery is probably ok. (my saab will go down to 8.5V and just about start)

Assuming battery is ok, check for earth or positive lead problems. measure the voltage accross the starter, is it the same as the battery when cranking. Measure positive terminal to ground (car chassis), is there significant volts when cranking?

If everything looks good as far as the starter then it looks like the starter but I'd guess battery or dodgy connections from you description.
 

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what you have is a volt drop on starting,
TOBYMACK is probibly right,if your car was starting before the battery problem,it's likly to be connections, check the battery terminal conections, remove them clean terminals and clamps, make sure when you refit the clamps there is a good conection, check earth to body, and earth from engine to body, this is important bad connections and a diesel won't start,if these are ok do the check tobymack says to test starter, when (or if it starts) put your meter across the battery terminals, (set on voltage) this reading will show the alternator charging rate, you should see between 13.8-14.00 volts any less alternator or fan belt tension should be checked, you could consider having a volt drop relay fitted to help starting
 

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Discussion Starter · #5 ·
I did put some halfords battery terminal protector on the old battery and terminals, so maybe that needs cleaning off, also you mention check earths well, I would if I knew where/what to look for. Obviously I've got a negative wire terminal, but other than that what/where do I look. Also the starter is quite awkward to get a multimeter too, but saying I can, what do I set the multimeter to? WOuld it be 20 volts like on a normal car electric test. Sorry to sound dense, but its the first time I've dealt with these kind of problems myself.

Cheers for your help so far.
 

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I agree with the bad connection suggestions... and the terminal protector could well be the culprit.

This would also make measuring voltages pointless, as it is the current which is important on starting a battery (which a std meter won't test unless it goes up to 100Amps - allowing for current spikes!). Hence guarages use specific battery heavy current testers.

Battery terminal protector should not come between the battery terminals and the connecting leads as it will create a bad connection.

A cloth or kitchen roll with Metholated Spirits will help clean it off. Ones the terminals and lead ends have been cleaned on the contact faces, you can re-spray the terminals once a good connection has been made and the clamps tightened.
 

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If your Cavalier is the same as most of the older Vauxhalls, trace the wire from the neg battery post and it should go straight to the top crossmember at the front of the engine bay. Vauxhalls often get a bad earth here, so undo the bolt clean everything up and do it up tight again. The other earth point that often causes problems is from the gearbox to the inner wing. If you look at the end of the gearbox from the nearside wheelarch (you may have to remove the archliner) you should see it. Again undo this and clean it up.

Neil
 

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Discussion Starter · #8 ·
Cheers for your help with all this Guys, you've been a great help. I am going to have a bash at cleaning the terminals today and see what happens then. Problem now is closer to all your homes. Last night driving home from work in the missus's Griffin (-2 outside!)I stopped and got a chinese, got back into the car started her up, and the battery light decided to stay on. Drove her home, turned engine off, started her again...still the battery light continued to stay on, opened the bonnet, everything looked OK, no slipped off aux belt, no terminals loose. I'm just hoping it ain't the bleedin'alternator!!!! Please God..not more expense this time of year!!
 

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Discussion Starter · #9 ·
Right, been out there today having a bash. Firstly cleaned all the terminals up, I could only find one earth point which was attached off the battery terminal and onto the front N/S wing. Cleaned everything, tightened everything back up, used a known good battery then cranked......again just a lazy crank and still didn't start.....I'm still at square one it seems......what can I do next other than remove the starter...which I don't wanna do as I said....its virtually brand new....

So then I went to the Saab, battery light still comes up....checked all belts/terminals in the daylight this time....and all looked fine...I'm assuming its the Alternator.Its charging at 11.6V on the dash or 12.5v off a direct reading off the battery. I'm going to keep on using it and hope it holds out for a few days. It should hoopefully just slowly discharge...I hope!
 

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ksowden1

you must have a earth strap from engine to chassis, this is usually bolted to the gearbox to engine bolts, or to the end of gearbox, if this is ok you will have to remove starter unfortunatly as they can go wrong (even new ones)take it to an auto electrician and they can test it for you,

your Saab
12.5 volts is not good enough, you need to see 13.8-14.00 volts across the battery, the alternator is not charging enough to replace voltage you are using, it WILL get worse and discharge to a point were the car will breakdown, this will happen quickly,you don't need to replace the alternator its the regulator which as failed,(its located at the rear of the alternator and held inplace by two cross head screws,(it carries the alternator bushes) it will have the bosh no's 1197 311 022 although the last 3 digits may not be 002 but they will interchange, you don't need to go to Saab either any auto electrical specalist should stock them, cost between £10-£20 depending on sorce, its not that bad to fit either, bit of a tight squeeze from top of engine,you may have to remove engine stabalizer, mutch easier from under car,you should be able to do this without removing alternator.

good luck
AYM
 

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Discussion Starter · #12 ·
Zeppelin, are you referring to my cav? If so does anyone know where the other earthing points are other than the one attached to the wing. I can't seem to find them but maybe I'm looking in the wrong places, after all this 1.7 TD engine is an Isuzu (don't ask!) If I do find it do I just clean everything up, check for breaks, WD40 them and then place everything back as it was.
 

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Discussion Starter · #13 ·
Also if I do find out its the starter thats packed up.....how do I go about getting my money back.As I've said he's 100 miles away now, but there was a 2 year guarantee with the starter and it did cost £250!!!! Could I send it through the post for him to exchange and would I be allowed to let someone test it, or would that invalidate the warranty. He is a member of the royal mechanics institute or something like that so I suppose theres that extra cushion if he refuses to pay up.
 

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Discussion Starter · #15 ·
Right, what am I looking for when I'm testing a starter Motor with a multimeter, and what wires do what that come off them, what should I have the multimeter set on dial wise. I am going to test the starter motor whilst its still in the car as I've had enough with it cluttering my house!
 

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Discussion Starter · #16 ·
Anyone know? I'm getting desperate now towards christmas!!!! Need to know how to test a starter using a Multimeter, and don't make it too technical as I'm new to using this multimeter lark!
 

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Fraid not, unfortunately.

Testing of a starter motor in situation, with a multimeter is not easy.

The starter motor takes 50+ AMPS (current) when turning over the engine. To test this you need a very powerfull current meter, and the meter needs to be connected in SERIES, with BIG cables. Definately not something which should be done, and most multimeters would simply blow up!

You can measure the voltage drop across the battery by:
1) Measuring voltage across the +ve and -ve of the battery with car turned OFF.
2) Measuring again when the engine the ignition key is turned to the starter motor position.

In position 2) their will be a lower voltage recorded. This may indicated bad earth, bad battery, or bad starter motor... but will not conclusively define the problem.

The only starter motor specific test I can suggest is remove the unit and:
a) Measure the RESISTANCE of the windings. If infinite (i.e. very high) resistance is measured, then the windings have burnt or broken, which is a fault with the starter motor. If a fairly low resistance (ohms) is measured, then the unit may be ok, but you really need to get a reputable service agent to test the starter motor.

Alternativvely, you could swap the existing unit with a known good one, and see if it helps.

Hope this helps a bit.

And happy new year to one and all.
 

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A bit late but....

You the best you can do with a voltage meter is to measure the voltage accross the starter terminals when cranking. If the volts measured at the starter are much less than the battery volts then you have a problem with either the leads or connections. (eg dodgy earth etc)
I'm not sure but I guess the starter is earthed though the engine? In this case measure volts from the two terminals in turn to the engine (find a bit not covered in oil!). If you notice the volts being much less than battery volts then work your way back up the wires until you find out where the loss is. If you can't find anything wrong then I'd replace the starter.

The only problem is you will have to work below/around the engine when it is being turned over and there are very high currents floating around. Be very careful not to put your fingers where they should not be or to short anything out!
 
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