Silly question of the day.

kinga · Post by **kinga** » 27th March 2019 - 8:09pm

Hi all,
Apologies for the really easy question.. I should really know this, but..
The 4 warning lights on my 68 fasty ..looks like 1 us side lights, 2 is main beam & 4 is oil pressure, but what is 3?
My 3rd light doesn't come on at all..I assume it's ignition..any idea why it wouldn't work..mine is standard engine although it does have a (Mazda rx7 I think) alternator conversion..
Marko..has it ever worked?
Thanks

Post by **purplepeter** » 27th March 2019 - 8:13pm

Generator
Probably not working 'cos of dodgy alternator conversion!

Post by **purplepeter** » 27th March 2019 - 8:14pm

It should only light when you first turn the key (before starting engine) & when your generator/belt fails

sparkywig · Post by **sparkywig** » 27th March 2019 - 8:40pm

Have you checked that the bulb's not blown?
If it has the alternator won't charge as the bulb is part of the exciter circuit to start charging.

kinga · Post by **kinga** » 27th March 2019 - 9:15pm

It's charging ok, but the light doesn't come on when I turn the ignition on.

Whilst I would like to get the light working, am I right in thinking that the lack of the light is not as important as on a type 1 engine, as the cooling is provided by a fan on the end of the crankshaft, so if the belt fails, the battery wouldn't get charged, but the engine cooling would still work?

Marko - are you out there mate? - has it ever worked, or is this as a result of the alternator conversion?

Thanks again folks.

Post by **broady_6** » 27th March 2019 - 9:36pm

You are correct regarding the cooling. It could be as simple as a bulb that's gone. What wires and what colours do you have connected to the alternator?

Post by **Editor** » 6th April 2019 - 1:33am

The reason that light should come on when ignition is turned on is that it is then connected to 12Volts. When the generator system gets up to 12Volts, that is in the opposite sense, and the net volts across the bulb is zero.
I suspect the conversion has not taken this into account, and/or the bulb is dud! It's certainly true of normal alternator circuits that the charging light is vital to excite the alternator.

Aaronslimvw · Post by **Aaronslimvw** » 8th April 2019 - 7:46pm

My ‘idiot light’ does not come on now either after doing an altenator conversion. The battery is definitely charging tho.

kinga · Post by **kinga** » 8th April 2019 - 9:13pm

Thanks guys - had a look at the weekend, and looks like I must have knocked one of the wires off the back of the alternator when I changed the plugs!!

It's usually something simple!

How embarrassing !!

Least its sorted.

Silly question of the day.

Silly question of the day.

Re: Silly question of the day.

Re: Silly question of the day.

Re: Silly question of the day.

Re: Silly question of the day.

Re: Silly question of the day.

Re: Silly question of the day.

Re: Silly question of the day.

Re: Silly question of the day.