Leccy Fuel pump and Relay advice

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Stesaw
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Leccy Fuel pump and Relay advice

Post by Stesaw »

So before I fit my 2.1 I need to fit a electic fuel pump.
I will be running on carb and I've already got the pump.
I also have a tracker fitted with its own relay that can be used to shut off power to coil / fuel pump and I've yet to find a decent place to fit the relay.

What I thought might be easy and neat to do is get the crappy fuel injection loom from the 2.1 that I have and use the double relay box (the one that sits above the coil) to fit the fuel pump relay in as well as the tracker relay.

In terms of wiring it. The relays in the box are both number 53 relays, one for the pump one for injection bits if I understand right?
Could I remove one of the relays and then do some rewiring to fit the tracker relay in its place and use the existing 53 relay to power the pump?.

I've been thinking that I want the tracker relay to kill power to both the pump and coil. Its just knowing what wires I need to add as well as splice into the existing main loom.




 
1985 LeisureDrive 2.1DJ 5 Speed syncro conversion project.
1979 LT 2.0CH Westy project

Stesaw
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Location: Coventry

Re: Leccy Fuel pump and Relay advice

Post by Stesaw »

Well that wasn't do bad. After drawing up some rough diagrams and sorting the pin numbers I've ended up with this. 
Image

Permanent Power into the relays has the inline fuse, which at the mo is 30amp, I will swap this for a 10 or 15amp. I thought about swapping out some of the wires as they are rated at around 17amp, but then again if swap to a 10 or 15amp fuse I guess I won't have to bother.

Tested it with the pump and a spare battery... it functions as I wanted. When I apply 12v to the switched cable the pump runs and when the ground is applied to pin 85 on the tracker relay it cuts power to the pump.

So just need to protect the wiring with some heat sleeve stuff, mount pump, wiring to the tracker. Then figure out where to put the permanent and switched 12v connections.
I am thinking perhaps alternator for permanent and coil for switched?

Also only the permanent 12v has a fuse would I need to also fuse the switched 12v?

(I will be swapping the ground cable for the right colour just incase that upsets someone) ;)
1985 LeisureDrive 2.1DJ 5 Speed syncro conversion project.
1979 LT 2.0CH Westy project

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Mocki
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Re: Leccy Fuel pump and Relay advice

Post by Mocki »

If you are only running on petrol , then the carb should have enough petrol in it to fire up the engine before the pump starts , so in theory you could take your switched feed from the blue wire at the alternator, which would mean the pump would stop as soon as the engine stopped in the event of a stall , or accident ? 

idealy you should use a Rev controlled relay , so that in the event of a  accident or stall the pump stops . 
saying that , I never have , my pump is fed from a relay triggered from the coil . 
Steve
tel / txt O7947-137911
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1989 2.1LpgWBX HiTop Leisuredrive Camper
1988 2.1 Caravelle TS TinTop Camper 
 

Stesaw
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Location: Coventry

Re: Leccy Fuel pump and Relay advice

Post by Stesaw »

Mocki wrote: 08 Jul 2021, 18:36 If you are only running on petrol , then the carb should have enough petrol in it to fire up the engine before the pump starts , so in theory you could take your switched feed from the blue wire at the alternator, which would mean the pump would stop as soon as the engine stopped in the event of a stall , or accident ?

idealy you should use a Rev controlled relay , so that in the event of a accident or stall the pump stops .
saying that , I never have , my pump is fed from a relay triggered from the coil .
Thanks Mocki,

In terms of the permanent 12v, would that be best done from the alternator? or should I run a wire from the battery? 
Running the switched from the coil is something I thought would be the easiest and cleanest due to the relays being sat above the coil, reading up on other threads that should be connected to terminal 1 +ve . Or as I don't have a rev controlled relay would It be "safer" to connect it to blue alternator wire so it would stop the pump in the event of stall etc. Also in relation to the switched 12v should that be fused as well?
 
1985 LeisureDrive 2.1DJ 5 Speed syncro conversion project.
1979 LT 2.0CH Westy project

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Mocki
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Re: Leccy Fuel pump and Relay advice

Post by Mocki »

I don’t think you need worry about the switched live needing a fuse , the pump is only being powered by the perm live , the switched live is merely a trigger for the relay …..

no need to run a wire all the way to the battery , either the starter motor main connection or the alternator main connection will be better . 

like I say , I have mine triggered by the coil , ignition off , pump off ! 
Steve
tel / txt O7947-137911
👀
________________

1989 2.1LpgWBX HiTop Leisuredrive Camper
1988 2.1 Caravelle TS TinTop Camper 
 

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