Log in

View Full Version : Charge light half on, and front oil seal.



SuperChad
17th December 2015, 08:48 AM
Hi all

Well the old girl is registered and cruising around town.
The other night I was driving home from work and noticed the Charge light never fully went out. Its bright at idle, and usually as the revs rise it goes out, now its still dull.
I thought it might be due to the extra drain of the headlights on etc.

This morning the same thing, with no electrics on.

Got too work and put it on a big battery charger we have here for an hour. Now when its idling, the light is bright, and at road revs, it just goes out.

Would i be right in thinking the alternator is not outputting much of a charge?
What would one expect the voltage to be at the battery terminals at different revs?

It does have an alternator, not a generator, and having just had it ALL rewired at an autoelec I'd be confident the wiring is all good.

New alternator?

And secondly, I need to replace the from timing case seal behind the pulley. I can see screws around the mud shield thankfully., What the easiest way to get the nut off, a deep socket on a rattle gun, or swing off the spanner? Its a 1-11/16th or 43mm isn't it?


Thanks

Dave

Homestar
17th December 2015, 09:18 AM
If you're sure the wiring is good, then it does sound like a lazy alternator. Once you start and rev the engine a bit to get the light to go out, you should see pretty much full output voltage at idle - I would expect 13.4 to 13.8 at idle and nothing under 13.8 with revs.

Could be just a set of brushes - if it's a Bosch alternator parts are cheap and readily available. Simple enough job too.

The front nut I just used a breaker bar while holding the engine from turning with a bit of rope stuffed down one cylinder via a spark plug hole. :)

JDNSW
17th December 2015, 09:50 AM
The warning light shows the difference in voltage between the alternator or generator output and battery voltage reference, which comes via the ignition switch. (Is it an original generator or is it an alternator?)

If the light shows dimly when the engine is above idle, it may indicate a faulty alternator or generator, but is just as likely to be showing a wiring fault. This is most likely a high resistance somewhere in either the circuit from the B+ terminal of the alternator or generator to the battery, or in the circuit from the battery to the voltage regulator or alternator via the ignition switch. (another possibility is the earth connection between the engine and the chassis)

In several cases where I have experienced this (one of them a Series Landrover) the problem was the ignition switch itself.

John

Cannon
17th December 2015, 10:30 AM
Our one was doing exactly the same thing.

New alternator fixed it right up.

JDNSW
17th December 2015, 12:53 PM
Undoing nut on crankshaft.

What is easiest will depend on what tools you have. Locking the engine is not a problem, handbrake on and top gear high range.

Should be fairly easy to get a socket on the nut, and to get along bar on it, but a rattlegun will work. Either way will need a deep socket, and if yoou don't have that a ring spanner will work a lot better than an open end one.

John