Fia Master Cutout Switch

[Guest gavinc]

have fitted a FIA cut off switch to the superspec..

 

all was working fine.

 

but now when you remove the key,

 

it kills the power to everything, inc the fuel pump

 

but doesnt cut the engine out.

 

the engine only stops when the fuel runs out.

 

is it the diode. if so where do i get a new one..

 

cheers gavin

[Guest chris brown]

have fitted a FIA cut off switch to the superspec..

 

all was working fine.

 

but now when you remove the key,

 

it kills the power to everything, inc the fuel pump

 

but doesnt cut the engine out.

 

the engine only stops when the fuel runs out.

 

is it the diode. if so where do i get a new one..

 

cheers gavin

 

I take it it had a diode across the switch to kill the alternator when the kill switch was used. If so then yes it has blown. It is not a good idea to use a kill switch as the ignition switch but should be used as a battery isolation switch after the engine has stopped. Most of the time you will get away with stopping the engine using the kill switch but if the alternator is supplying allot at the time the switch is operated then there is a chance of blowing the diode. Also any lights that are on when the kill switch is used will have excessive voltage applied and may blow.

[Guest gavinc]

chris thanks for your quick reply

 

yes there is a diode..

 

which i presume some how earths out the coil..

 

to stop the engine running..

 

will have to look at replacing the diode then

 

 

 

I take it it had a diode across the switch to kill the alternator when the kill switch was used. If so then yes it has blown. It is not a good idea to use a kill switch as the ignition switch but should be used as a battery isolation switch after the engine has stopped. Most of the time you will get away with stopping the engine using the kill switch but if the alternator is supplying allot at the time the switch is operated then there is a chance of blowing the diode. Also any lights that are on when the kill switch is used will have excessive voltage applied and may blow.

[Guest chris brown]

yes there is a diode..

 

which i presume some how earths out the coil..

 

will have to look at replacing the diode then

No it is not the coil but the alternator that it stops charging and now it has blown the alternator is still supplying a voltage so keeping things going but because it is no longer connected to the battery its voltage will climb that is why I said any bulbs that are on could blow. BTW the voltage can get as high as 30 volts and do a power of no good to all manner of things. This is why I say always under normal circumstances use the normal ignition key to start and stop the engine. Kill switches are there as the name implies to kill the electrics not necessarily (in fact very rarely) the engine in the case of a crash

[Guest Paulxe20]

How have you wired it up?

The FIA switch from Rally Design has 3 contacts.

The large 1 to isolate the battery, then 2 auxiliary switches,1 normally closed and 1 normally open.

Run the supply to the coil via the NC, when the switch is operated the coil looses its supply and the engine stops.

The NO switch is used to dump the alternator output to earth via a large white resistor if the engine is running when the switch is operated.

Or - as the small auxiliary switches are prone to failure, just use the 1 large switch to isolate the battery earth from the car, that stops everything and doesn't damage the alternator.

[miikae]

How have you wired it up?

The FIA switch from Rally Design has 3 contacts.

The large 1 to isolate the battery, then 2 auxiliary switches,1 normally closed and 1 normally open.

Run the supply to the coil via the NC, when the switch is operated the coil looses its supply and the engine stops.

The NO switch is used to dump the alternator output to earth via a large white resistor if the engine is running when the switch is operated.

Or - as the small auxiliary switches are prone to failure, just use the 1 large switch to isolate the battery earth from the car, that stops everything and doesn't damage the alternator.

 

 

Mine is the same FIA isolator switch and wired as above as per the fitting guide that came with it .

 

Mike

[Guest Paulxe20]

Test the auxiliary switches.

With the red key in the on/run position, Switch 2 should to closed and power the coil. Turning the red key should open switch 2 , kill the ignition and stop the engine instantly.

 

The contacts get dirty and fail to close, so the car won't start, you must be special!

I've had about 6 fail so we always carry 2 spares on a rally.

[Al Milton]

Daft question, but is an isolator switch a requirement for SVA? If so, is there a poular or standard type?

 

Long way from my electrics yet, but any info gladly absorbed.

 

Cheers

Al

[Guest Ian & Carole]

No its not a requirement for SVA.

 

Not got one myself but some like to be able to turn every thing off when left in workshop for long periods or when left "vulnerable" to scrotes and toe-rags

 

Place the switch out of sight and it can be an half decent anti-theft device.

 

Ian J

Edited May 9, 2008 by Ian & Carole
which eye cud spel

[miikae]

No its not a requirement for SVA.

 

Not got one myself but some like to be able to turn every thing off when left in workshop for long periods or when left "vulnerable" to scrotes and toe-rags

 

Place the switch out of sight and it can be an half decent anti-theft device.

 

Ian J

 

 

Thats all the reasons why i fitted an anti scrote-toe rag switch , plus my steering wheel is hanging in the hall .

 

Mike

[Al Milton]

Thanks Ian and Mike.

 

Good idea to fit one then, so will do when the electrics are ready to install.

 

Cheers

Al

[miikae]

If you plan to fit one early in your build then you wont waist any battery cables , as you will need longer cables to go through the bulkhead to the switch , i think i got my cables from Premier together with the quick release battery terminals and crimped cable ends , a one shot got the lot .

 

Mike

[st3v3nw]

I fitted one under the scuttle as an anti theft device and also to isolate the battery when the car is left alone for a while.

 

they are best if they are hidden as you only need a pen to stick in the hole and you can make the contact to start the engine up.

 

As said before, not an SVA requirement as such but it does ask for an immobiliser so it does come under that category.

 

ste

[Guest andy philp]

Just a slight word of warning to rover engine super specs the ecu is adaptive it learns the best ignition and fuelling map to suite your driving and engine wear over 100 miles or so, fitting a cut out switch will reset the ecu to default mode every time you use it If you really wont one them try and get a cut out with a code saver (low fused link) fitted learnt the hard way !

[Al Milton]

Thanks all, valid comments as usual. Certainly like the idea of not wasting cables!!

 

Cheers

Al