23 replies to this topic

[Cooperman]

Just one small additional point. If you turn the battery cut-off switch to 'Off' whilst the engine is running,unless the cut-off switch incorporates an ignition cut-off as well, you can easily burn out the alternator as the engine will continue to run and the current generated will have no-where to go.
Personally on my rally cars I use an FIA-Approved cut-off switch which cuts positive power and ignition which is the only type of switch approved for international competition.

Like this one, second one down.
http://www.vehicle-w...ns/battisol.php

Yes, that's the one I always use.
However, I've twice in the last 16 years had the ignition part fail and had to 'jump' across the terminals to get the ignition to work. The first time was during a special stage and I was not best-pleased. Maybe i have been unlucky and I would be interested to know if anyone else has had this problem.

[Dan]

As I said before, FIA switches are well known to be garbage. You've been lucky to only have 2 fail really. Think about how much it actually gets switched on a race car, if used as an isolator on a daily driver they don't fair well at all.

[Cooperman]

As I said before, FIA switches are well known to be garbage. You've been lucky to only have 2 fail really. Think about how much it actually gets switched on a race car, if used as an isolator on a daily driver they don't fair well at all.

You are right there Dan. I now have a 'switch by-pass switch' (not strictly allowed under MSA/FIA rules, but the switch is disguised) so that if the ignition via the cut-off fails I can get ignition immediately. Unfortunately there is no option switch-wise for motor sport as the cut-off is mandated and checked as you know. I don't know where a higher quality one can be bought and that one seems to be what everyone uses.
For everyday use it could prove to be a problem, although it's the ignition circuit which has failed on both of mine, not the battery main supply so with a by-pass you are still 'fail-safe'.
Mine is fitted between the seats s it has to be able to be reached by either crew member whilst strapped in and here is an external pull-cable coming out just in front of the screen on the RH side.

[Dan]

I think there is an FIA approved relay type, with remote switching by any number of connected push switches. It's a big and chunky 180 amp disconnector, expensive though and heavy.

[Yoda]

For an in car isolator, to save the risk of a length of "live " cable between the battery and cut off switch, do it by breaking into the battery earth cable, ie, replacing it with two cables to and from the switch. i think also it will help prevent the switch from burning plus for an alarm or stereo constant feed, you can connect to the battery negative directly and fit the solar charger to keep the battery topped up. By isolating the earth, the whole of the car is electrically isolated, not just a cable!

This is how i intend to do mine in the summer because the large live cable running the length of a Mini has always bothered me. I have a direct earth cable to the starter bolt already for another reason, and done away with the standard earth strap in the boot, so i intend to break into this cable with the isolator switch.

Any thoughts on this idea would be welcomed.

Edited by customcart, 31 January 2011 - 09:59 AM.

[Yoda]

Not sure if this would work with an oem alarm as fitted on later models though.

[Wil_h]

not hard at all! really easy and can get any good one from places such as burton power or sparco ect. all you have to do is separate the positive wire as close to the battery as possible and fit it in:) so simple if your D.I.Y applicable

its impotant to keep it as close to the battery (positive feed) as possible


hope this helps, harri

Ok maybe a stupid question but why is it important to keep it as close as possible to the battery. I have seen rally mini's with the battery cut off in the cabin??

Surely if you are using a good quality cut off mounted correctly then it should not be an issue or am i missing something??

well, long answer, if your running the battery cable through or even under the car and you have a crash and the battery cut of switch is next to your seat inside the car When you turn that off you will still have a cable running underneath you that is LIVE. this is NOT GOOD. This can cause a fire. If its in the boot next to the battery then there is no risk of anything bad like a fire or worse happening.

Its deffinatly the most safe place to put it an me and my dad (racing driver and mechanic all his life) highly recommend you put it there,


hope this helps, Harri

This, and other bits of this thread, don't really make sense for this scenario. Basically as I understand it, the guy wants to have a cut-off switch that can be operated occasionally when the car is stood for long periods, so an FIA type switch will be fine for occasional use. Putting it in the boot may make sense for the occasional operation, but in this instance, putting it next to the starter motor will off the same safety as there is at present. Like every other Mini, the battery cable runs back to front unprotected.

Personally, for my race car I have the battery on the cabin with the switch right next to it. It would actually be very difficult to have the battery and the switch in the boot and make the car compliant with the MSA regs. Not impossible but it'd be a faff.

[robsrallymini]

I had a FIA master switch on my previous car for over 10 years with out any problems,
got it from demon tweeks

[stu_cooper]

my mate has one of the red switch type ones shown on the link earlier on. its fitted to his oldschool rally look alike saab which is his usual daily driver. he has never had any issues and his is a cheap halfrauds 1.