Page 1 of 1
Over charging.
Posted: Fri Sep 25, 2015 12:39 am
by mark1gls
Driving home tonight in the light rain my wipers suddenly started to go faster than normal (both front and rear) I thought it was a bit strange so stopped and checked the relay and pulled it out all clean and no rusty connections popped it back in and checked the wipers and back to normal, started the car and drove a bit more and the wipers started to go fast again then it stopped raining. I then got home and I could hear some hissing from under the bonnet, I just thought the car was a little hot as I was stuck in traffic, I then opened the bonnet after putting the kids to bed and having dinner and battery acid had sprayed all over the engine bay! When I started the car the battery was hissing after about 2 minute of running and the wipers was going fast.
I've cleaned the main earth's (gearbox and chassis arm) and the earth to the alternator but when I start the car the after about 30 seconds the wiper and lights etc all are getting to much current and the battery starts hissing.
Is there some thing I can do or is the alternator faulty and will I need a new battery as it's a sealed Bosch one and alot of acid has come out and took the paint off my inner wing, eaten through my plastic vac hoses and left horrible marks on the radiator, starter motor, front pannel, HT leads, dissy cap etc…

Oh how I wished I had looked as soon as I got home.
Any help would be great.
Mk1 Scirocco with the early type fuse board if it make any differance.
Re: Over charging.
Posted: Fri Sep 25, 2015 8:23 pm
by jimmy h
Alternator is knackered Mark, mine did this many years ago but not to the extent you describe. I'd say the battery has had it too. Think yourself lucky, I boiled off about two new battery's before I realised it was the alternator!
Re: Over charging.
Posted: Fri Sep 25, 2015 9:42 pm
by mark1gls
I think I've fixed it, I got my multimeter and I was getting 18v going to the battery, I took off the voltage regulator and the bushes are very worn and there is hardly any thing left on one, lucky I've got a spare alternator that's been in the garage for 20 years so I checked the regulator bushes and they seem alright so cleaned up the connections and alternator popped it on and I'm now getting 14.5v at the battery. The alternator I took off is very rough when I spin it and the other day it started to make a lot of noise like the bearings was going so perhaps me spraying WD 40 into it did not help but it did quieten down the noise?
Any one know if I just buy a new regulator it will be alright?
The faulty one is a Bosch with Motorola regulator.
New Bosch battery on order to pick up from Eurocarparts tomorrow and only £40.
Any one know where I can get some black plastic vacuum hose going to my dissy as mine is pitted and cover in white dots from battery acid! Just hope it's not going to eat through the radiator as the plastic bit of that is also marked....
Re: Over charging.
Posted: Sat Sep 26, 2015 4:11 am
by james butler
you really need to wash as much of the acid off as you can and through bicarbonate soda to nuetralise the acid, otherwise it will continue to eat away at your engine bay.
be very very carefull removing that old battery and have a bucket handy to put it into and again throw bicarb all over it.
you can replace the vacuum hose with copper brake line then connect it up either end with rubber vac pipe.
the problem your going to have now is what damage has the acid done eating into stuff like the insulation on the engine loom and light loom which runs right next to the battery.
if this shorts then you could have an electrical fire on your hands in the near future and can be very serious and hard to put out once started.
Re: Over charging.
Posted: Sun Sep 27, 2015 10:52 pm
by mark1gls
I used bicarbonate soda to clean what was left after several washes with water and soap the a good wash with a hose pipe the main loom near to the battery has not been covered in acid it seems most of came out the other side of the battery towards the engine a little towards the inner wing and main loom, this is what I'm left with, anyone know where I can get new plastic vac hoses as mine are looking terrible!
All the white looking dots are where the battery acid has been, it even hit the dissy cap, head and engine block!

White acid run marks all down the radiator

The inner wing.
