Hey polo people. Can anyone who has changed the stock mechanical fuel pump on a mk2 to an electric pump, advise on the inertia switch please? More specifically, is there a particular switch you can recommend? What's a good position to mount it? At the moment i'm running just a regular disposable plastic fuel filter. Is it worth installing any more than that with an electric pump? 

Thanks for stopping by and any guidance you can give. 

Mk2 bready, 1983, 1043cc

I've been looking at this myself but decided to go a different route.

 

Fuel pump relays on VWs from around then had a sensor wire connected to the HT coil.

This means if the engine stops then so does the fuel pump.

Seems this replaced the intertia switch approch.

 

Personally - I like the sound of both intertia switch and engine running sensors. I suspect the interia switch was discontinued due to them cutting fuel occasionally when hitting potholes etc.

 

If you have trouble finding that type of relay or find them too expensive - look at the fuel solinoid cut relays that are required by law on old LPG cars, these are available well under £10.

 

Let us know what you implement.

1 minute ago, kbs said:

I've been looking at this myself but decided to go a different route.

 

Fuel pump relays on VWs from around then had a sensor wire connected to the HT coil.

This means if the engine stops then so does the fuel pump.

Seems this replaced the intertia switch approch.

 

Personally - I like the sound of both intertia switch and engine running sensors. I suspect the interia switch was discontinued due to them cutting fuel occasionally when hitting potholes etc.

 

If you have trouble finding that type of relay or find them too expensive - look at the fuel solinoid cut relays that are required by law on old LPG cars, these are available well under £10.

Basic plastic fuel filter is fine - just be sure to use the low pressure kind of fuel pump or your float valve wont cope!

Let us know what you implement.

 

Fords in the 90's fitted an inertia switch

I'm using a Ford inertia switch. I tested it by dropping from 1 metre and it cut out and reset simply. It is bolted to bulkhead horizontally.  It's never cut out over a pothole or a Siteguard speedbump (sometimes 12 per day).i

It didn't cut out when I had a queuing low speed frontal prang, but I think it is working as intended.

 

An alternative is a Wells PS121 oil pressure switch, but the wiring's a bit complicated.. 

Cool. Thanks dudes. I'm looking at a facet posi-flo. The low pressure one. Just looking at options to go with it. Thanks again.