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Installed electric fuel pump, need some help

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I actually posted this yesterday in the thread I started two weeks ago, but it looks like they just scroll off into the past based upon the orig post date, so I apologize for the double posting.

Car is a 1970 with dual 45DCOE carbs

Ok, I put my new Pierburg electic fuel pump, installing it under the car near the right rear axle. It's very quiet compared to the big sucker that was on there, but it not's a full successful effort yet. A couple of things are going on.

First, the big red warning light on the dash, the one that the hand brake illuminates, has been coming on and off since then. That's new. I'm not sure what's it trying to tell me.

After a 15 min drive, I went back and felt the pump. It was pretty hot to the touch. Is this normal?

I'm wondering if the pump is drawing too much current? I fed the pump from a connection off the wiring harness up under the dash near the washer relay. Two green wires ending in a insulated male spade connector that becomes hot when the ignition is in the 2nd position.

I added the fuel filter that originally was on the car to the input of the pump as per the pump installation instructions. Is is possible the fuel filter is installed backwards causing the pump to work too hard? I didn't think the fuel filter had any markings on flow direction, but I could've missed it. Or could it be clogged, causing the pump to work too hard?

I guess the first place to start is to understand what the warning light is saying.

Any suggestions or comments from folks?

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Red warning light is likely coincidental, if your switch behind the brake handle gets loose & moves a little, it could vibrate in & out of contact. I'll throw out 2 ideas for electric fuel pump wiring.

Run a separate 14 ga wire from the battery with an inline fuse to a relay, feed the relay coil from the battery & then tap the oil feed sensor wire & use that to feed the other side of the relay coil, then at least if your motor stops, there is a saftey shut off for the pump.

Only drawback is if the car sits too long & fuel in the carbs dries up, you need a switch to temporarily ground the oil sensor to start the pump, or else you have to crank it for a long time to get oil pressure up.

Do you know from the source you tapped which fuse is inline ?

Have you measured the voltage at the pump ?

Filter is likely to flow good either direction, and the pump is gonna get warm/hot to some degree. & be sure to run wide open at daytona, or else you might get flamed for putting an electric pump on your car. I used to run the ring myself :-)

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So you're saying the red light is only for the brakes? I guess I could pull the connector to the handbrake lever to test that theory.

I don't know what the source is for the connector I pulled from. I like the idea of running a relay and fused line to the pump. I already have the hot lead wired into a inertial kill switch for a safety switch.

And the fuel pump was already there when I bought the car, so I can blame it on the PO. But it was this huge hulking thing that was LOUD and installed in the trunk with a backyard engineering on/off switch under the driver's seat and wiring run under the mats.

I elected to replace it with a pump sourced to run carbs,and mount it under the car where the tii pumps are and properly wire it.

Thanks DanOKC.

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Car is a 1970 with dual 45DCOE carbs

I put my new Pierburg electic fuel pump, installing it under the car near the right rear axle. It's very quiet compared to the big sucker that was on there

the big red warning light on the dash, the one that the hand brake illuminates, has been coming on and off since then. That's new. I'm not sure what's it trying to tell me. = HAVE YOU LOOKED IN THE E-BRAKE

BOOT AT THE SWITCH? AND HAVE YOU LOOKED AT THE LOW BRAKE FLUID RES. FLOAT SWITCH?

After a 15 min drive, I went back and felt the pump. It was pretty hot to the touch. Is this normal? = YES - THE REASON FOR SOME CAR MAKERS

SUBMERGING THEIR PUMPS IN THE FUEL TANK - FOR COOLING AND LONGER LIFE

I'm wondering if the pump is drawing too much current? I fed the pump from a connection off the wiring harness up under the dash near the washer relay. Two green wires ending in a insulated male spade connector that becomes hot when the ignition is in the 2nd position. = WIRES SHOULD NOT BE HOT, AND THE PUMP SHOULD NOT DRAW MORE THAN 8 AMPS . CHECK YOUR WIRING AND GROUND CONNECTOIONS FOR SOLID

CLEAN CONTACTS TO CLEAN BODY GROUND CONNECTIONS

I added the fuel filter that originally was on the car to the input of the pump as per the pump installation instructions. Is is possible the fuel filter is installed backwards causing the pump to work too hard? I didn't think the fuel filter had any markings on flow direction, but I could've missed it. Or could it be clogged, causing the pump to work too hard? - ALL FUEL FILTERS ARE DIRECTIONAL - LOOK AGAIN FOR AN ARROW - BUT IT WON'T CAUSE RESISTANCE IN FLOW

I guess the first place to start is to understand what the warning light is saying.

Any suggestions or comments from folks?

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Two green wires ending in a insulated male spade connector that becomes hot when the ignition is in the 2nd position.

I think he means "hot", like 12 volts present, not to the touch hot, I almost responded to that too.

& yes, check the brake fluid cap, there is a switch in the top, you may find the brake light problem there.

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Two green wires ending in a insulated male spade connector that becomes hot when the ignition is in the 2nd position.

I think he means "hot", like 12 volts present, not to the touch hot, I almost responded to that too.

& yes, check the brake fluid cap, there is a switch in the top, you may find the brake light problem there.

Yes, exactly that. Sorry for being unclear. Pump hot to touch, wires not hot to touch.

Yah, gotta love English...

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Just so there isn't too much confusion - only 74 and later cars had a switch inside the handbrake boot to illuminate the round "brake" light on the cluster, when the handbrake was actuated. All US cars had the low brake fluid switch in the reservoir, though.

Now...this MAY or MAY NOT be related - but Euro cars also had a LOW FUEL level warning function built into the cluster. (Euro sending units have an extra spade connector on 'em. ) Not sure what years had this. Too lazy to check now. :-)

So, I suppose, if that light comes on in a later Euro 2002...you have to just guess what's gonna give out first.....brakes....fuel...or meltdown of the rear shoes!

Paul Wegweiser

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Just so there isn't too much confusion - ...

Now...this MAY or MAY NOT be related - but Euro cars also had a LOW FUEL level warning function built into the cluster. (Euro sending units have an extra spade connector on 'em. ) Not sure what years had this. Too lazy to check now. :-)

Paul Wegweiser

Ah Paul, I think you hit the nail directly on the head there. I'm definitely flirting with low fuel as I was drawing it down prior to installing the new fuel pump and associated lines. I wanted to minimize any collateral damage in case things went wrong. And having the little bit of fuel slosh around as I got on the throttle and off again would perfectly explain the light's behaviour.

I knew you guys wouldn't let me down. Thanks!

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