fuel pump power

[davo]

G Day all i am changing engines from 1600 to 1800 with my son Problem is changing from mechanical pump to electric pump Have pump can someone tell me were i get power from engine bay for pump.Is it a 9 volt feed ? Thanks for any help

[Nick]

there should already be power there as all the wiring harnesses are identical from base model to sl/x sl/e. if not then just run a wire from the ign at the fuse box to the back of the car

[Adam]

Hello Davo,

Nice to hear of a good father/son project. First things first, #DON'T" use a gemini factory pump, they are notoriously unreliable and will fail just in time to REALLY inconvenience you.

However for safety's sake you must pull the power 'trigger' from the original 9 volt fuel pump power feed. It is one of the six wires which comes out of the alternator regulator... I cant remember which one for the life of me, but if you can't work it out I can look it up. (I just worked it out with a test light and multimeter)

I would recommend an external pump, fed a nice healthy 12-14.4 volts by a independantly switched relayed controlled power feed...

Or in english, you take the power from the original battery feed, run it through a switch (so you can turn the pump off if you want), then into the 'trigger' side of a relay. Pull 12 volts from the positive side of the battery STRAIGHT into an inline fuse, then into the 'power' side of the relay, from the other side of which you run a wire to the power feed for the pump.

Again, if you need more help, I can draw a wiring diagram.

Now, for extra-niftiness, get yourself a three way on-off-on type switch and pull 12 volts from the 'accessory' circuit, then use that instead of a basic 'off-on' switch in the trigger side. Run power from the 'acc' circuit to that switch so you can prime the fuel system (useful after carby changes), but do #NOT# run the engine off that, as it ruins any potential safety benefit.

Any questions?

[CuGem]

Yup I have a Q Adam. My twin DHLA40 conversion is almost ready to happen, and Iain Stewart whose tuning them for me and someone else said not to worry about a new pump. Either run as is or put 12V to the TD stocko pump. Have you ever tried that? Bear in mind this is just a show pony street application on a mildly worked G161, with a P&P TX head and 1800 pistons. I'm gonna experiment as is and tell you how it goes.

[Andrew65]

I ran a wire from the tail lights.It got 12 volts but meant you had to have the parking lights on(or better)for the fuel to flow.
The pumps arent weak its the wireing thats sus.

[Adam]

There is a good reason why the fuel pump is wired as it is... By pulling the power feed from the alternator, the fuel pump only runs when the engine is running, thus if you have a crash and you are trapped/unconscious in your car, the full pump will stop and you won't be burnt to death... a fairly good idea I think.

[Woz]

...and seeing that most of us here are the type that boot through traffic, have a high rate of rubber loss on our tyres and generaly have a greater chance of smashing our car weather it be in the bush or getting cut off by a VL (no offence to anyone here with a vl ) id say that running the fuel pump off the alternator is a fine safety idea, that certainly gets my vote .

-woz

[Dracko]

I've just got my fuel pump and altinator replaced. I've got a 100 Amp altinator from a mazda rx7 (i think).

anyway the auto elec had to cut out the resistor that was changing the 12v from the altinator to 9v to get my new external pump to work.

i say do what you have to do to get your car going right

[davo]

I will get back to you when i have it right Like to stick with gemini parts Son has 3gemini 2 on the road I will tell you the full story when i have time Thanks Dracko

[davo]

Thanks for the best reply adam Now the full story We bought a hold 80 model gem for $400 with g1800 5speed good panels etc.(luck i guss) spent 4 months looking (rust in body) Sons car is a 84 model. Keeping in tank pump from 80 model to 84 model Do not want to spent $ on another pump. Do not think 84 model has a power trigger. Did not have a electric pump on 84 befor. Would this change alternator regulator wires ? I happy to run 12 volts to pump safely through a relay Might pay to look it up for me.Will have some parts left over from 80 model exhast panels etc. All in good cond.Wiring diagram would be good. Thanks again Adam

[davo]

New to this site.Son has bought a 80 model gem $400 with g1800 5speed spent 4 months looking(luck i guss) panels good body shell rusted changing everything over to sons 84 model takes time. Son has tx coup just for a runabout till 84 is finish. It is running a standed in fuel tank pump Good pumps but make sure a good earth hope this helps

[davo]

Got my vote too. Only have to work it out hopefully adam can help me out unless you can help out Son has 3 gems 2 on the road. Changing parts around on them Tell you the full story later. thanks for any help

[Racegem]

Welcome aboard Davo,

I know it's probably a pain in the arse to do, but if you have the TE you're ratting bits off, you could always pull the wiring loom and alternator from the TE and install into the TG. That's if you really want to keep Gemini bits. Although it might not be the cheapest option, an aftermarket pump is really the best one. It allows modifications to the motor without having to worry about fuel starvation. There's a limit to what the standard pump will supply.

Another thing too, my first Gemini I owned I had bought and owned for thirty minutes. I was halfway home and the alternator died. And seeing the alternator runs the fuel pump, my brand new set of wheels left me stranded 20 kms from home with no tools.
Food for thought.

Yonnee.

[davo]

looks like anew 12volt pump any idea of cost? Son wants to go that way i was thinking of cost. Thanks