weird Electrical Problems

[rio678]

Hi everyone

my Minor is playing up alot

firstly the fuel guage started to shoot to full all the time, now it's dead, the horn is working occasionally ( i have cleaned all terminals etc) and the car ignition light is on and is not charging properly

[Willie]

an interesting spread of faults! When you say it is not charging properly
I assume that the red charging light does not go out when you rev up?
Do you have a dynamo or an Alternator? What year is the car, I
presume it is pre 1964 since it appears to have the ealier type fuel gauge
(the black faced type gauge cannot 'flick to full' it only rises slowly).

[rio678]

Hi !

it's a 68 with dynamo, the light does not go out at all and it's a black faced dial too .... It use to flick to full like there is a full current going to it, now it doesn't work at all

[Peetee]

Run the engine in the dark. If there is any sparking evedent in the dynamo the bushes are worn and need replacing.

[aupickup]

the horn could be the horn push, is the spring inside ok and making good contact

[MoggyTech]

Fusebox connections or fuse box itself for horn.
Charge bulb blown or dynamo or regulator for ign light.

[rio678]

would the regulator behind the speedo be the problem for the fuel guage?

and would the regulator be the problem for my temporary problems, the heater stopped working yesterday and now works again, is there a way of testing the current coming out of the dymano?, i have cleaned all contacts and fuse box is new.

[Orkney]

Bad earth?

[Packedup]

Fuel gauge - A short in the loom? Or a short between the sender terminal and something resting on the tank

Could the horn be the brush/ pencil between wheel and column?

Ign light - Dynamo, regulator, more tired wiring (in most likely order).

[overider]

Hi, rio I had similar fuel gage fault and the heater was intermittent. I traced it to the voltage stabiliser at the back of the Speedo. However, this stabiliser was sent faulty by a fault at the fuel pump. So before changing the voltage stabiliser check they is not a fault on the feeds too and from that first.

This was my posting
http://www.mmoc.org.uk/index.php?name=P ... ic&t=16836

http://www.mmoc.org.uk/index.php?name=P ... ic&t=16944

Might be worth a read.

[bmcecosse]

First you need to get the dynamo charging - to test you need a VOLTMETER - costs v little in Maplins etc. Set to DC volts and attch to the battery. Engine off should read ~ 12.4 volts - engine running and charging should go to 13.8/14.2 volts. If it doesn't rise - it's not charging. Assuming the fan belt is present - and reasonably tight - the first check is to fit new brushes - easy to and cheap. If that doesn't sort it - come back. The other problems sound like bad connections at the fuse box and/or at the volt stabiliser.