New starter motor, but still just clicking!

[spinal_pap]

Morning all,

Just easing myself in to the wonderful world of Surf ownership and seem to have one of the recurring problems:

Soon after purchasing the truck i got the click on starting, then nothing. Decided to get the starter motor replaced instead of refurbing contacts.

All was well for a couple of weeks, but since the cold weather it never has enough charge to start up - so i just get a click the same way as i did prior to replacing start motor. When i hook up my jump start box it fires up straight away.

Tested both batteries with multimeter - about 12.3 when engine off and 13.8 when idling with blower and headlights on full. Interestingly when i switch the rear demister on as well the charge drops below 13.

So jump start this morning then a 20 minute A road journey to work. Park up, let the engine idle for a minute with all the electrics switched off. Turn engine off, then try to turn on again. Nothing but a click!

Are the batteries funked or do my problems run deeper than this?

Thanks for any suggestions, so glad i found this forum - the advice really is first class.

cheers

[Apache]

Try putting a meter on the batteries when trying to start. See if the voltage drops right down when you engage the starter.

Its also worth checking the earth connections from the batteries to the bodywork, and all connections to the batteries for corrosion and tightness.

If the batteries are not sealed, its probably worth uncsrewing the fill holes and checking the electrolyte levels and condition of the plates. If they are furred up or buckled, they are shot.

<edit> When you test the capability of the alternator, press the 'idle up' switch as the alternator will rarely support the full electrical load of the vehicle with the engine at idle - which is why you saw the dip when you put the rear screen heater on.

[tonupteabag]

you could have a duff battery get it checked properly first to save spending money unnecessarily

[NiftyNev]

If voltage drops to below 10V when starter is engaged then batteries have had it.

Nev

[Hawaii]

afternoon all

fully agree - it's your batteries. If you have the 2 battery set uop and only one of them is knackered then it will pull down the good one as well.

As prices are too bad at the moment (both batteries from Toyota £114.00) change 'em both.

Can't take risks on non starting in this chilly weather

ta

hawaii

[spinal_pap]

Thanks guys,

Good shout to check the drop in voltage while engaging starter. Will check that tonight before i go ahead and buy new batts, but agree this seems most likely fault. Just wanted a sense check from people who know what they are on about first!

appreciate the advice.

[timelord]

Hi. Checking the batteries with a multimeter is not really going to tell you the full story. The reading could be low but that might just be because the battery is pretty flat. The only way to test a vehicle battery properly is "Under Load". That means using one of those two pronged/handled affairs that have a meter permanently attached between. (I believe there may be some specific hand held meters/testers that purport to put the battery under load, I am not sure how good these are, but I don't think they could handle the amperage of the effective short circuit through the meter. Not sure?) Anyhow, the battery must be fully charged before the test. Make sure any charging gasses are vented first. Disconnect the battery. Then firmly place the prongs one on each battery terminal for approx 10 to 15 seconds(any way round is ok) . The meter on the tester will have a sliding coloured scale. Green at the edges with red in the middle. The meter needle should stay in the green. If it progresses into the red, then the battery is duff. This is the recognised motortrade test for a battery.
Also, a battery may appear charged with a normal voltage meter, say after leaving it on charge for some hours or driving a reasonable distance after starting the vehicle, but often a cell may have degraded. This will only show under load, ie, when you try to turn the starter motor, especially on a cold morning. Under load, the cell integrity collapses and the battery will now read flat with the multimeter whereas before the under load condition it showed ok with voltmeter.
An extra bit of related info is that when freshly charged from a batt charger or by alternator, the reading of the voltmeter can read approx 1 volt higher than the actual real stored charge voltage of the battery. This is due to a "surface charge". This is an abundance of free electrons still clinging to the surface of the electrolytic plates within the battery. As soon as any load, even a small bulb is applied to the battery, this "surface charge will evaporate".. Just a handy tip to know if you are trying to assess the working condition of any battery.
**Do not overcharge a battery by excessive boost charging & beware explosive gases build up by the charging process. (Hydrogen - I vaguely remember)**

I suppose that with a voltage meter, you could test the voltage of the charged battery and then try cranking the engine for no more than say 6 seconds. Then test the battery voltage again. If it has dropped to 11.5volts or less, than I would think the battery has a defective cell.

I have leant my two prongy tester thing out - with the weather an all - but you are welcome to call by and check it out if you are close - Rochdale area. G.

Also - cold weather = inefficient electron transfer between the cell plates. So = death of batteries already on their last legs.
I know a load of you know this already, but I am noting it on here to help those who don't. This site has been a godsend to me since aquiring my surf last month. Ta folks!

[timelord]

That bit about a volt drop while cranking the starter motor.. Could that not also be the case if the starter had a partial short to earth whilst operating? I am sure I had this on one of my vehicles years ago. Just wondering? The voltage in the battery after this cranking/test method would not return to an acceptable level if a cell is shot, but may if the starter is shorting whilst operating. Just musing it over. If I am incorrect, then please let me know for my future use. Thanks, G.

[Apache]

The starter motor *is* a partial short to earth. It's impedance is very low when operating, which is why it will draw so much current. As Nev and I said, a drop to below ~10V or less when cranking will indicate a shot battery.

If there is another short somewhere when operating, the battery state after cranking will be the same as if there wasn't a short, or slightly worse. It wont be better than with just the starter operating as there is even more current flowing.

Agree a multimeter wont tell you anything other than what the open circuit voltage of the battery is *without a load applied* but using the loads attached to the car (starter cranking, full beam etc) will give you a quick and dirty indication of battery state if you know what you're looking at.

It's actually an accredited Def-Stan 61-5 way of testing vehicle power systems to test max load / power budgets etc, though in addition I use external load banks. You'll probably find that Def-Stan on t'internet - and if you're involved with vehicle power systems, I dare say you'll find it an interesting read. 'Def-Stan 61-5 Part 6, Issue 6, Part A' is the one you want.

[lord lucan]

if you have an immobiliser this can be at fault , current goes to the starter solanoid but not enough amperage ,run a live lead to the starter small wire [normally black and red}make sure your ignition is off and the car in park

[funkykebab]

If i turn my key it does nothing with my immobalizer on....won't click or anything.

Matt