Inertia switch behind Wiper drive?

[HersnotHis]

Hi

I have a gold coloured cylindrical device approx 3.5" (90 mm) h x 1.3" (32mm) dia. It is labelled "Inertiaswitch Ltd" and has 2 connections. This is mounted vertically on the bulkhead immeditely behind Wiper Motor. Cannot find reference in wiring dias.

Any info of what this does?

TIA

Thanks

[PBH]

Hi this is the fuel cut off in case of an accident the knob on the top comes up if it is triggered and the fuel pump electric are disabled to sop fuel being pumped into a frontal damage. I is also there to baffle you when the engine wont start as a curb bump or jar can trigger it.

Peter

[DJT]

Sounds like your is from another vehicle or an aftermarket version. The Stag one (also fitted to some Rovers, Jags and other Triumphs of the era) is a grey plastic cylinder. There are several threads on here showing how they work and how they can be dismantled for cleaning. Hopefully your works in the same way and you know how to reset it if necessary.

Stag ones are reputedly in short supply, but this guy seems to have a few stashed away:

http://www.ebay.co.uk/itm/151122629038?ru=http%3A%2F%2Fwww.ebay.co.uk%2Fsch%2Fi.html%3F_from%3DR40%26_sacat%3D0%26_nkw%3D151122629038%26_rdc%3D1

[HersnotHis]

Thanks to both

I think ours is the standard one - it looks just like the linked ebay item except someone has painted it gold at some point in the past!

[TR5convalescent]

It is similar to the one fitted to the TR6. It is placed there so water can get in causing its ball to go rusty thus giving an intermittent current. This can sometime be resolved by giving the ball a good polish with emery paper (stop sniggering at the back). In TR applications it is usually the cause of high resistance in the pump supply causing vast expenditure on injectors pumps fuel lines PRVs and other big ticket items.

I got rid of mine and the car instantly ran and started better.

[Kevin Garrod]

It is similar to the one fitted to the TR6. It is placed there so water can get in causing its ball to go rusty thus giving an intermittent current. This can sometime be resolved by giving the ball a good polish with emery paper (stop sniggering at the back). In TR applications it is usually the cause of high resistance in the pump supply causing vast expenditure on injectors pumps fuel lines PRVs and other big ticket items.

I got rid of mine and the car instantly ran and started better.

Cleaning the ball will have no effect since it plays no part in electrical connectivity. It is just a weight to dislodge the copper connectors.

[hansolo_uk]

I got rid of mine and the car instantly ran and started better.

details ? just removing makes car run fine ? no need to bridge wires with resistors ?

[rac]

Wires need to be linked together as it is simply an off/on switch-not a good idea to remove though

[Staggard]

It is similar to the one fitted to the TR6. It is placed there so water can get in causing its ball to go rusty thus giving an intermittent current. This can sometime be resolved by giving the ball a good polish with emery paper (stop sniggering at the back). In TR applications it is usually the cause of high resistance in the pump supply causing vast expenditure on injectors pumps fuel lines PRVs and other big ticket items.

I got rid of mine and the car instantly ran and started better.

Talking to a man that knows ( assessor) it is also a great get out of jail free card for insurance company's not to pay out on a claim no matter how big or small. Apparently its part of his check list to make sure its present and functioning. Just a thought

[davidf]

A lot of people (including myself) take the power for the electronic ignition amplifier from the downstream side of this switch, so the engine would also cut immediately in the case of an impact.
Interesting to know opinions on this.

[stag8manod]

Sounds a good idea David.
Cheers Ian A

[V Mad]

.............I got rid of mine and the car instantly ran and started better.

Ask your insurance company if you can add it to your list of modifications. The reply might be interesting.

[Motorsport Micky]

In my experience of the commercial world, companies and manufacturers are quite wary of supplying you with devices that allow you to hang upside down unconscious trapped in the car whilst an electric device pumps 10 gallons of petrol onto a car fire !
Strange that - they even go to the bother of supplying you with a device and extra wiring and complexity in the loom which costs them money and then they don't charge you extra for it, I think they've missed a trick, don't you ? Doh !

Micky

[Staggering About]

here's how it works.

http://www.grampianstags.net/inertia.htm

Alan.

[Staggard]

A lot of people (including myself) take the power for the electronic ignition amplifier from the downstream side of this switch, so the engine would also cut immediately in the case of an impact.
Interesting to know opinions on this.

Here is my scenario, you are cruising down the motorway fairly crowded suddenly there is a piece of shredded lorry tyre you have nowhere to go so you run over it with just enough of a bump to jolt the inertia and cut the engine dead. Now I know this can also happen with the fuel pump but with fuel starvation you do get a bit of warning. I personally think it is a bit of a crude piece of kit as its performance relies on the strength of a magnet which must vary and fade over time. Please remember this is a personal opinion just something I would not do