junkyard racer

Installing a new dellorto carb system, removing a ton of crap from the engine bay, and installing a holley blue fuel pump has led to some issues I am hoping someone can help me with.

Long story short, I have no power to my fuel pump and I can not figure out why.

Can anyone tell me, from looking at these pictures, if I have something disconnected or something that would cause me to not have power to the fuel pump? I drove the car into the garage (the fuel pump worked just fine when I parked it) now it has no power.

Also, when I installed my fuel pump, I bypassed the (what I think) is a one way valve or something??? -basically I have my line straight from the tank to the pump to the carb...well tank > holley pump > filter > holley fpr > carb. Is this ok?



I did not modify this wiring, was like this when I got the car

Rotaryfreak702

So did it run after the holley pump install?

junkyard racer

no. it has not run (had power) since the tear down. somewhere, some how something got messed up that it no longer has power.

RotorMotorDriver

iTrader: (1)

I cant think of anything off the top of my head that would be under the hood that would cause the pump to stop working. Did you check your fuses? Maybe you accidentally shorted something when wiring it up? Dont 84s only pump fuel when cranking?

Just FYI, my pump was a little bogged down running on the stock wiring and the rest of the electrical system was a little strained, so I wired up a relay for it. If you have a volt meter, you should be able to check the wires under the storage bin at the plug and see if its getting power when you're cranking.

~T.J.

junkyard racer

I havent tried it when cranking, but with it in the on position, it has no juice. I will try that. Thanks.

Also, I thought about doing the relay deal...
https://www.rx7club.com/1st-gen-archive-71/fuel-how-install-carter-fuel-pump-holley-fpr-529605/

But I thought if am going to do that, why not build my own under hood harness from nothing? I will start a new thread.....

junkyard racer

Turns out, you sir are correct. 11.xx when cranking. It is not sending fuel through the system though? Maybe the power isnt sufficient to power the pump? I undone the pump, hooked it straight to the battery and she spun no problems. Connected to the harness, nothing, or not enough to push fuel rather...and its not loud, at all. Slight hummm....which from what I am told, holley blue pumps scream.

j9fd3s

iTrader: (3)

on an 84-85 car, the trailing ignitor sends an RPM signal to the emissions control unit, which turns on the fuel pump relay, which then sends power to the pump.

junkyard racer

I read on a boat forum that these pumps dont like moisture, and collect moisture very easily. They had mentioned undoing the bottom of the pump and inspecting it for rust. Turns out, mine had a little corrosion. A light scuff of some sand paper and a tiny dab of grease...I put it back together and went straight to the battery....it spun a little rough at first then got super loud and then spun awesome. I havent had time to put it back on the car, but I am hoping that did the trick.

junkyard racer

so...then removing the emissions crap would cause this then? I am getting power when I crank the engine.

RotorMotorDriver

iTrader: (1)

Not unless you removed the emissions ECU. If you are getting power at the plug for the pump, then its all working fine.

As for the pump, it is a pretty loud pump. I dont like mine too much for that reason. Get it back in the car now that you cleaned it up a little and see if it spins. There SHOULD be enough power at the pump plug to run that blue pump. If you're still having problems, you can wire up a relay back there. Even if it does work, I highly recommend the relay because of the strain it puts on the rest of the electrical system. Heres a picture of mine:



I just used a standard Bosch automotive relay. If your battery is under the hood still, run a fused (7.5 amp or so within 12" of the battery) 10 or 12 gauge wire to the back of the car along the door sill. Connect that to terminal 30 of the relay. The rest of the wires are fine at 14 gauge or so.

Connect the two wires from the stock chassis harness side of the fuel pump plug to terminals 85 and 86 on the relay (doesnt really matter which goes to which here).

Connect the positive wire of the fuel pump side of the plug to terminal 87 of the relay.

Connect the negative wire of the fuel pump side of the plug to a secure ground on the chassis (I used the cruise control computer mounting screw).

Thats it! When you crank the ignition, the relay will see the power signal from the chassis side of the plug, switch "on", and flow the power from the battery at terminal 30 out the other side at terminal 87 down to the pump which is grounded to the chassis.

~T.J.

j9fd3s

iTrader: (3)

my friend had a bridgeported rx3, and you could clearly hear the holley pump over the engine....

the carter is much quieter, although at least mine doesn't flow anywhere near its rated spec

junkyard racer

Figured out my problem, and it is 2 fold.

1) hooked the factory fuel pump up, and she pushed fuel.
2) the line it pushed the fuel through was the opposite line I had connected for my fuel line to my FPR. Switched lines and the car fired right up.

Long story short, the holley pump I bought on ebay listed "worked great on my chevelle" is actually bad. -or the pump somehow went bad between the time he took it off and I put it on.

At least I got my problem fixed. -or know what the problem is/was

RotorMotorDriver

iTrader: (1)

I had a Carter on my 7 before it was stolen. I also run a Carter on my Toyota 4x4. This time I said "why not try out the Holley since I have to buy a new one anyway". I wish I had bought another Carter. Too damn loud, lol.

~T.J.

junkyard racer

SO many stories of what is loud and what isnt. Truth is, I have a rotary with a open carb, somewhat loud exhaust and it will probably only get louder as time goes on.

Why complain about a loud fuel pump? A loud fuel pump also lets me know its working. lol!

RotorMotorDriver

iTrader: (1)

So do I, but the pump is an obnoxious drowning buzzing sound. The Carters are "loud" too (not really), but this is more annoying than anything. I can barely hear the intake/exhaust over the thing at a cruise, and not at all at an idle. All you hear in the car (and standing outside it), is that damn pump.

~T.J.

junkyard racer

Bah I've also read many way to mak it quieter. Wrap it in electric tape, rubber washers.....

RotorMotorDriver

iTrader: (1)

Yeah, I plan to put some more rubber between it and the chassis, but its a little obnoxious when the Carter does just as well (if not better because I had issues with mine too), yet is half the annoyance and doesnt need all the extra work to go back in and make it quieter.

~T.J.

junkyard racer

Sweet. My carter got here less than 24 hours after I ordered it. Granted I am in Indiana and Jegs is in Ohio, I was still very pleased I was able to order my pump after I ate dinner and it was on my door step when I got home from work today. -standard shipping.

RotorMotorDriver

iTrader: (1)

Sweet! Wanna trade for a Holley blue? It works great

~T.J.