whats the best relay and cable to use when re wiring the cossie fuel pump, can i use a pink ford fuel relay (rst/xr3i) as i have a few of them about ?

 

i have just been asking all this as i am fitting a group A pump and thinking bout rewiring her

click on this link

http://www.vehicle-wiring-products.e...e/homepage.php

i am thinkin of going with a 30 amp relay type b the ref number is r20b

but i suppose the relay u said is all ok

 

I used 10mm cable and a 40a rated relay,i ran a positive and a negative.

 

what positive through relay and just a negative wire straight from battery to pump ?

 

2 secs and i'll try and find the diagram m8.

 

how u going to rewire your pump?

 

i'll probably go from battery positive through a 30 amp fuse, then i will use something like a good quality amp wiring kit cable to the spare wheel well, then t off of the knock relay thats already in there for my trigger wire, fix my 70amp 4 pin relay in the boot and connect the wires up, as for negative side i will probably just earth the pump to the floor, but im no expert im just going off what people have done and this is the conclusion ive come to.

 

cool i am going to use a 15/20amp fuse on the feed from the battery run it down the original course of the wiring bring the new wire up to where the cut of switch is and locate new relay there,then cut the wires coming from the cut off switch to the pump and use them as my trigger for the new relay(so it keeps the cut of switch in the loom for safety reasons!)then run the new feed down to the pump following original wiring then feed a new earth agian following original wiring all the way to the battery

 

i used a 40 amp 4 pin relay and 35 amp wire got it all from maplins

i ran 1 live and 2 earths from battery to spare wheel well

used the original fuel pump live as trigger to relay, new live to relay and new earth

then from relay new live to pump and the other earth from battery to pump

works spot on

 

same as me then mate, i see your location is london im only down in oxford (m40)

 

doesnt it make the battery look a bit untidy, also wasnt it a pain to conseal all those wires as they must be quite thick if good quality ?

 

lol yeh mate in enfield if i see black smoke coming from oxford or if u see smoke from enfield we will know wot has happened

 

coswurv

heres a link to my resto where you can see whats involved and how it looks

https://passionford.com/forum/viewto...180&highlight=

i carnt remember where abouts it is but somewhere on pg2 id imagine

cables arnt that thick they dont need to be

 

just seen your thread on year car xr4x4rs so u did not use both the wires coming from the cut off switch to the pump as your trigger for the new relay as a live and earth??

 

here you go mate

 

nice diagram so u have to run 2 earths from the battery then one for the trigger relay, one for the fuel pump?

 

here you go mate this is how ive done mine, i think i got th pins correct but will have to double check as carnt remember at the mo



reason i didnt use my interia switch is becuase i plan to run a stero in te boot and the bass used to knock my switch in my old xr lol

but if alls you need to do is put inline with the new live going from relay to pump

 

Dont run the earth from the battery as you will get alot more resistance use an earth point in the boot

 

hmm so how would do it to keep my cut off switch in ??would have to use the wires coming out of the cut off switch ?but where is the original earth?for the cut off switch

 

how so?

 

the cut off switch uses the live for the pump not the earth

so you need to put this to the new relay

then from the relay the new wire for the live you have to put the inertia switch in

thats how i would do it

but you may be able to keep the original wiring and just take the original live to the new relay

 

i have not looked at the wiring in the boot at the mo so u only have one wire going from the cut of switch to the pump ?then the earth goes from the pump to the earth in the boot?

 

You will build no resistance that is going to make shits worth of difference at this level by earthing at the battery, it's complete crap, but is banded about often.
Use the formula,
R= pL/A to determine resistance, if you want to be fussy.
Copper wire has a resistance of 0.000999 ohms foot@10 Gauge and 20Degress Celsius.
tabetha