Over charged!

Well, the battery is - not me! I got home and there was a nasty burning type smell from the front of the car. When I opened the bonnet (carefully!) I could see bubblig form one of the cell covers on the battery. When I checked the voltage it was 13V, rising to 17V with the engine running and more bubbling from the battery. I had been wondering if the alternator was on its way pout because the dash lights tend to flicker and there is an occassional screeching noise from the car even though the alternator belt is correctly tensioned - todays events have kind of confirmed it.

When I got quotes to replace the alternator both garages said there are two different types of alternator fitted to a 2002 Jimny (hardtop) - how can I tell what I have? Suzuki wanted £400 to supply and fit a genuine Suzuki alternator, the other garage wanted £250 to supply and fit a non-Suzuki alternator. I'm tempted to try the job myself with a secondhand alternator off eBay, but they are only ever described by the year of Jimny they fit so how can I tell what type I should get? My other questions are how easy is this job for a novice to do, and how can I tell if the battery is stil OK?

The alternator regulator has gone.

Is there an auto electrical specialist near you who will recondition your alternator?

The regulator is a plug in unit, but the back of the alternator has to come off first.

To remove alternator.

Get underneath and look up.
At the bottom of the alternator there is an allen key bolt partially blocked by the belt. It goes right through the alternator mountings, at the back is a welded nut that wont undo.

Try and undo it. If it won't come undone pay the £250. (You will not believe how much trouble it is to remove the alternator if that bolt is seized, took me half a day)


If it does, go back up top.
Disconnect the battery.
Remove the large cable - 10mm nut.
Unplug the other cable
Undo the bolts holding the adjuster plate.
Remove fan belt
Remove the long bolt you undid first
The alternator comes out.

Buy one that looks the same, take it for reconditioning, or exchange it at your local motor factors.

Before you let go of yours, check that the replacement has the pulley on, or you will be in trouble!

Thanks for that. I have a feeling the bearing could be on its way out too given the screeching noises the car is fond of making, which funnily enough were worse today than it has been.

The screeching will be the fan belt slipping when the alternator is working hard.
Sorting the alternator and readjusting the belt will stop that.

Excellent. I think I'll let the garage take care of it. I only have a set of allen keys and regular allen key socket bits - sounds like I'd need the longer reach allen key bits for the socket set and even with those there's no guarantee of success. Given the state my wheels were in and the effort to free the bolts off of those I don't hold out much hope that things will be any easier under the bonnet!

Interesting this.

I always have a LED voltmeter showing in my Jimny. It came off my motorbike when I sold it. Damn bike regulators regularly go kaput, and then you get the maximum output from the alternator boiling the battery.

It's a bit paranoid doing this, but once bitten........

It also tells me if I'm making enough volts to charge the battery on those crappy dark Winter mornings - what with the heater, wipers, headlights & other toys gobbling the power.