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Re: Van now running! - a couple of teething problems

Posted: 14 Aug 2010, 21:28
by pionte
defiantly worth checking your earth straps, I have just fitted a leisure battery and when I tested the voltage I was only getting 12.7v, I removed the earth strap, cleaned the metal and refitted and then was getting 14.2v. If in doubt fit an extra one £4 from Halfords.

mart.

E D I T : meant to say 14.2 v when engine running .

Re: Van now running! - a couple of teething problems

Posted: 14 Aug 2010, 21:43
by Oldiebut goodie
Remove all the earths and clean up and reconnect is a good starting point. My alternator has an extra earth from its body to the engine - presumably some previous owner had some earthing problem and solved it that way.
Your battery should be at 12.7v after fully charging.
Another thought - have you put a larger diameter pulley on the alternator or are you using the original from your old one?

Re: Van now running! - a couple of teething problems

Posted: 14 Aug 2010, 21:55
by fix
So what are you classing as earth "straps", the earth wires in the engine bay are just standard thin wire. Not like the ones I've just seen on the halfords website.

From memory there are two or three earths near the coil and one on the engine, not one directly from the alternator. Isn't the alternator earthed just being bolted to the engine?

I'm using the old pulley, the 90amp alternator is from a golf or similar so the pulley is different to the T25.

Re: Van now running! - a couple of teething problems

Posted: 15 Aug 2010, 10:04
by Oldiebut goodie
Battery to chassis
engine to chassis
gearbox to chassis.
should be heavy braid.
It's these assumed earths that give the problems sometimes. The alternator is only earthed if the engine is earthed correctly and then can give problems especially when using non standard items.

Re: Van now running! - a couple of teething problems

Posted: 15 Aug 2010, 12:57
by fix
Cheers for the info I will have to take a look under the van, but I'm positive there isn't a braided earth wire on the engine, I only put the engine back in last week and would have seen it.

I won't get a chance to work on my van now till next wkend, so ill fit new strap/s and see what happens.

Re: Van now running! - a couple of teething problems

Posted: 15 Aug 2010, 13:08
by Oldiebut goodie
Usually there isn't an engine one but putting one on is easier than getting under and messing with the gearbox one if your old and decrepit like me. (easier to keep an eye on for general mankiness)

Re: Van now running! - a couple of teething problems

Posted: 15 Aug 2010, 16:27
by fix
Dont mind gettng under then van, spend enough time under there!

Ive cleaned up the contacts on the gearbox earth strap, will see if it makes a difference.

Re: Van now running! - a couple of teething problems

Posted: 16 Aug 2010, 12:22
by fix
Well I cleaned up the gearbox earth points and the alternator has gone upto abit over 12 volts, it keeps on going up with everything I do but its still way off 14 volts.

Re: Van now running! - a couple of teething problems

Posted: 16 Aug 2010, 15:26
by Oldiebut goodie
Battery to chassis earth point?

Re: Van now running! - a couple of teething problems

Posted: 16 Aug 2010, 19:22
by fix
Will have a look at that next, haven't even noticed a braided wire attached to the battery but I'm sure there will be something there.

Does the fact everything I do pushes up the voltage even though not enough mean anything?

Re: Van now running! - a couple of teething problems

Posted: 16 Aug 2010, 19:52
by Oldiebut goodie
Just follow the thick black lead to the chassis. Give both ends a good clean up.They stopped using braid for some reason some years back.
Are you using a dodgy test meter - is it's battery dying?

Re: Van now running! - a couple of teething problems

Posted: 17 Aug 2010, 09:39
by fix
Will do, cleaning it up can only help.

No the battery is brand new, left the multimeter turned on last time so had to buy another.

Re: Van now running! - a couple of teething problems

Posted: 17 Aug 2010, 10:13
by ermie571
Hi Fix,

apologies if this is WIIIIDDDDDEEEE of the mark....but I think I was experiencing similar probs to you - good voltage at alternator, pooh at battery. Poor starting. Sluggish. Poor charging of leisure battery.

Mark had a ganders, and traced 2 thick red wires from the alternator to the balck box in the engine bay. From there they went off to the starter I think. Anyways....on opening up the black box, he found the red wires fixed to a bolt....only they weren't red...they were kind of green and corroded!!

So now the ends have been remade, and I have the distinct feeling that they now go straight to the starter, and somehow link to the bolt in the box as well.

Once done, huge improvement in charging and starting!

Twas very hight resistance at the bolt.

(but this is an early van, but running a transplanted 2.1 was 1.9 - maybe it will help you?)

regards

Emma

Re: Van now running! - a couple of teething problems

Posted: 17 Aug 2010, 16:35
by fix
Thanks for the reply its a good point but not for my problem, my alternator isn't kicking out enough power nevermind at the battery!

I'm tempted to put a seperate engine to alternator earth and see what happens, but also check the battery earth.

Re: Van now running! - a couple of teething problems

Posted: 18 Aug 2010, 17:54
by jpennington
I suggest you make sure the alternator is working before spending a lot of time redoing the earths. You say it's from ebay, so it might just be defective :o
Measure the voltage between the alternator +ve terminal (the big one with the red wires attached) and the alternator body. You should get over 12v at tick-over, rising to around 14V if you speed the engine up. You may need to scratch the multimeter probe on the body to get a good contact. If this is fine, then you can start checking the earths, but if not, then your alternator is the problem.


BTW my DJ has a fat earth braid from the left side of the engine (on a bolt that holds the narrow metal coolant pipe to the cylinder head) to the body (on a bolt just below the coil). Original fit.

jp