Questions About Battery V, Condition, Drain

[Simes 248 2 Cars]

Then I cranked the starter with the above still switched on. It struggled a bit, but not as bad as on Sun, and fired after a few turns. The voltage dropped right down to about 10v on the first turn, but went up a little bit again as the starter was cranking and the starter did sound stronger with each turn before it fired.

 

With the engine running, it's seeing about 16.5 v.

 

You shouldn't see more than 13.7v when the engine is running.

Sounds like the regulator has packed up - unfortunately these days it means you need to replace the alternator.

[welshpug 1,657]

16.5 never seen more than 14.5v on a good alternator (well apart from when I tested a truck and got 28v )

 

There are places about that can replace the regulator, finding that place is often tricky though.

[jackherer 543]

If its hitting 16v stop running it! My mates merc started overcharging, it got up to about 18v and then the contents of the battery went all over the engine bay, boiling battery acid everywhere which wasn't pretty.

[GLPoomobile 958]

I'm pretty sure it wasn't charging so high before, so this must be a recent fault. I've tested the battery on numerous occassions and on some of those occassions I checked it with the engine running, and I'm positive it wasn't showing such a high voltage before. I would have remembered because I thought it was odd to be that high.

 

So yes, I do plan to leave it alone until it's sorted.

 

I need to get a new alternator then. I don't have time to be hunting down somewhere that can do the regulator, I just need it swapped out ASAP. Got Edinburgh trip in a couple of weeks, and I still need to get to the bottom of my strange whining noise, and now this. f***ing typical.

 

Bloody expensive from GSF too. If I can't get a decent 2nd one ASAP, does anyone know of a good supplier with reasonable prices? I don't expect them to be cheap for what they are, it's just that I really can't afford the expense right now.

[jackherer 543]

The strange whining noise might be the alternator, that would be handy, two birds with one stone

[GLPoomobile 958]

The strange whining noise might be the alternator, that would be handy, two birds with one stone

 

I'd love it if that were the case, and it did cross my mind, but I doubt I'll be that lucky. And it seems I have already not been that lucky

 

This morning I have swapped the alternator. A truly joyous task given the current weather - the wind making it seem sub zero outside. I've absolutely frozen my arse off, and it's bloody difficult dealing with fiddly nuts and bolts when you've lost all feeling in your fingers. Add in the fact that I had to pull the bloody inlet manifold off to get at the alternator, which was still a struggle to get out because it was a fat bastard 90a jobby.

 

So in goes a 70a sourced from Miles, and delivered by Sarty (thanks again guys). I connect everything back up, start the car.......................and I've still got 16v + Mutha f***er

 

I now bring your attention to my earlier comment

but ironically the battery in the MM was drained as I think I had left it switched on. It still had a display but was just reading 1 when connected to the battery (worked fine after swapping the battery)

 

Having bought a new Duracell 9v battery and whacked that in the mulitmeter, it's now showing 14.6v with the engine running, and a more realistic 12.5v with the engine off (previously it was starting at about that and rising slowly before levelling off at 13.6v. That in itself should have been a warning sign). So there was nothing wrong with the frigging alternator, it was a duff battery in the multimeter giving a false reading.

 

Mutha f***er........again

 

Now to go for a test drive and see if the little c*nt still whines.

[jackherer 543]

I've had exactly that problem with flat batteries in multimeters. The one I have now has a low bat warning but my old one didn't.

 

Analogue multimeters don't suffer from this, they only use the battery for resistance measurements, when reading voltage they use the signal being measured to deflect the needle.

[GLPoomobile 958]

I've had exactly that problem with flat batteries in multimeters. The one I have now has a low bat warning but my old one didn't.

 

Analogue multimeters don't suffer from this, they only use the battery for resistance measurements, when reading voltage they use the signal being measured to deflect the needle.

 

Just to rub salt in to the wounds, my multimeter does have a low battery warning. I ignored it, because I tested the battery before I put it in (using my analogue multimeter) and it seemed OK. I figured it was just low enough to put the warning icon on, but not totally drained. Besides, it seemed to be giving a normal reading. Now I've learned the hard way, having a low battery can give s*it readings.

 

I can't work out my analogue meter though. It has a weird scale and I can't get my head around the settings and how it reads

Edited November 28, 2009 by GLPoomobile

[Galifrey 1]

I can't work out my analogue meter though. It has a weird scale and I can't get my head around the settings and how it reads

 

Usually the scale is different depending on the sttings, do you have a pic of it you can post?

[GLPoomobile 958]

As per my latest topic

http://forum.205gtidrivers.com/index.php?s...=0#entry1021241

I've found the cause of the starting problem.

 

Headgasket failure around one headbolt was letting coolant seep in to the cylinder. The little bit of coolant was causing higher compression so the starter couldn't cope. By about the 3rd or 4th attempt I guess it must have expelled the coolant in to the exhaust and then the starter would turn normally.

 

Just realised I've worded this as if it's conclusively proven. It's not, but I'm certain it's the case. Everything adds up.

[Tom Fenton 1,542]

Easy way to prove is to do a compression test, the suspect cylinder will be down if there is a head gasket problem. Just because it is leaking out of the front doesn't 100% mean the fire ring has gone, my mate and my track car ran weeping coolant from the front of the headgasket for 3 years before we changed it, with no other ill effects apart from a brown stain down the front of the block and using a bit of coolant.