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drop in voltage

Posted: 10 Mar 2011, 13:23
by blankville
hi folks, we have a 1983 t25 devon pop top, after a decent run we are getting a serious drop in voltage on the restart, i have checked all the connections on the battery and starter and they all seem to be in good order. Its not tha tshe wont start its just that she sounds like she wont at first. its usually the 2nd or 3rd time i cranked her she starts no prob. The van starts very well from cold

look forward to your replies

cheers

Davie and Claire

Re: drop in voltage

Posted: 10 Mar 2011, 13:31
by 1664
If you are measuring the voltage at the exact same time as you're cranking the engine the voltage will drop considerably due to the cranking load

Re: drop in voltage

Posted: 10 Mar 2011, 13:33
by BOXY
How are measuring the voltage drop? If it's across the battery terminals when the engine is cranking how low is it getting? My first suspect would be the battery.

Re: drop in voltage

Posted: 10 Mar 2011, 13:41
by blankville
hiya, im only noticing the voltage drop off the noise its making on the restart, i havent actually measured it as such, it seem to take a real dip after a run as ive said. the battery is pretty new...

Re: drop in voltage

Posted: 10 Mar 2011, 14:02
by kevtherev
the voltage drop off the noise its making on the restart

Your measuring voltage by it's noise? (new one on me)
what is "it"

c'mon give us a hand

Re: drop in voltage

Posted: 10 Mar 2011, 14:04
by BOXY
Do a search for slow start and there will be a few discussions about possible causes. How do you hear electricity by the way?

Re: drop in voltage

Posted: 10 Mar 2011, 14:09
by blankville
kevtherev wrote:
the voltage drop off the noise its making on the restart

Your measuring voltage by it's noise? (new one on me)
what is "it"

c'mon give us a hand

hi "it" is the noise of a flattish battery i am assuming-please dont take the pi$$ im new to all this and trying to learn...

when i try to restart the van its as if the battery charge has dropped then suddenly it starts, i remember an old ford doing something similar years ago and if i remember there was an issue with the starter bearing, wondered if it was something similar?

Re: drop in voltage

Posted: 10 Mar 2011, 14:19
by blankville
BOXY wrote:Do a search for slow start and there will be a few discussions about possible causes. How do you hear electricity by the way?


Hi Cheers will do, ok then i have a slow starting vwt25, obviously i cant hear the electricity but ive been motoring enough to recognise the sound of a battery sounding as is its flat.

Re: drop in voltage

Posted: 10 Mar 2011, 14:26
by blankville
found a few folk on here with the same issue-seems not to bother them too much and is quite common....

thanks again

Re: drop in voltage

Posted: 10 Mar 2011, 15:34
by Mocki
ok...... it IS common.... there are a few reasons.....

1.the battery is a stupid long way from the starter, so voltage drop is a problem, specially with 20 year old cable
2.the "earth" for the starter is via the gearbox nose, one single "earth" lead..... age related corrosion probs
3. the bushing in the gearbox bellhousing may need replacing.
4. the starter may be getting past its best
5. the ignition timing maybe a little too far advanced
6. the battery "earth lead" maybe past its best of not connecting well....

remember... dirty connections get HOT, turning electric into heat uses lots of power..

Re: drop in voltage

Posted: 10 Mar 2011, 18:41
by kevtherev
blankville wrote:
kevtherev wrote:
the voltage drop off the noise its making on the restart

Your measuring voltage by it's noise? (new one on me)
what is "it"

c'mon give us a hand

hi "it" is the noise of a flattish battery

No pee taking fella but your use of English is odd.
batteries are silent.... starter motors make a noise so I assume you meant that.

Re: drop in voltage

Posted: 11 Mar 2011, 10:20
by blankville
hi, sorry for my poor terminology guys-as i say im very new to vans and quite enjoying the challenge to be honest. This forum seems to be really handy for help and tips and it seems most folk have came across most of the probs already-which is a good thing.

we really love our van and hope to chew through the issues steadily and get her ready for the summer

thanks again y'all

Re: drop in voltage

Posted: 11 Mar 2011, 10:36
by pionte
Hi Blankville,

dont take the comments to heart, everyone on here is really helpfull , and likes to have a laugh with, not at people , mine does the exactly the same, and to be honest If I could be bothered I am sure that an hour or so tinkering with the things suggested would sort... but to be honest it always starts so I dont worry about it

Re: drop in voltage

Posted: 11 Mar 2011, 10:59
by eatcustard
Kev

There is such thing as "voltage noise."

Re: drop in voltage

Posted: 11 Mar 2011, 12:26
by kevtherev
I here power in overhead lines ... but thats about 50,000+ volts or whatever

but batteries are silent



believe me... not the voices eatcustard