Club 80-90 Forums

Hi all had my y reg t25 2.0 Aircooled devon for a couple of years now and all that time i've had it ive never had a charge goin to my battery any way decided to tackle it today and found that there was a wire coming from the alternator with an inline fuse holder which had been smashed to s**t by something maybe sucked in by the alternator itself anyway put a new one init and tested and i'm getting a reading of 13.8v. just wondering if 13.8 is a decent reading? and should there be an inline fuse there or it something a previous owner has bodged in and if so what size fuse should be init i've got a 10 amp init now and seems to be fine.

No need for a fuse
13.8 is ok

so someone has bodged one in then? Are you saying i should do away with it completly and just join the wires together

How many wires are attached to the alt...just two?

one thick, one thin

As said 13.8V is spot on, but when you say =

probey28 wrote:Hi all had my y reg t25 2.0 Aircooled devon for a couple of years now and all that time i've had it ive never had a charge goin to my battery

I take it you mean your leisure battery? (or have you been re-charging your main battery with a domestic charger every day )

Theres 3 wires coming out the plug. 2 thick red ones and 1 thinner blue one this is the 1 that has the inline fuse on it

Yes i'm ashamed to say that i have been going out init and charging it up when in got home.

As said, get rid of the fuse. Essentially the blue wire is the trigger for the charging.

So you have 13.8 volts on the thick red wire = that is all good then.
So your battery is not getting the 13.8 volts, so it is simply a case of tracking along the positive (+) lead from the battery back to where it eventually leads to the red wire on the alternator. There must be a break somewhere. This should be very easy to check with either a meter or even a bulb on a bit of wire. By the way, the fact that it starts up off a charged battery OK means the earth (-) lead from the battery is OK and the thick red lead from the battery to the starter is OK too. (you can forget about the blue wire for now, just tape it up so it cannot short out on any metal bits).
I will guess it is the lead that goes from the alternator to the starter that is duff in some way.

Ok, one step at a time!
13.8volts is good as it should be on the two (?) red wires with engine running. This is the correct alternator charge voltage but can be in the range 13.8 - 14.2v.
The blue wire just starts the alternator charging when engine starts, should not need a fuse.
On a wbx there are two reds which go to the little black box of relays and connections on the left in the engine compartment. This supplies power to run ignition and other engine and vehicle services.
The power is then taken across to the starter motor and connects to the LARGE wire which goes to the battery, this completes the charging circuit.
The battery cannot discharge through the alternator, due to one way diodes, and the large wire on the starter motor is only connected when you turn the key to 'Start' but is always connected to the battery.

Unless things are significantly different on the air-cooled your battery should now be charging.
If not check these wires and connections!
Mine also has two reds at alternator to take charging current.

I stand to be corrected but the above is put forward in good faith and this is also a common wiring arrangement!

Regards
Jon