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No power to fuel pump


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I have a 82 Brat that i've been restoring. One of the problems it had was a knocking sound behind drivers seat, was told its the fuel pump making noise. So i replaced pump with a simple 12 volt replacement pump, was not the subaru OEM replacement. Car has sat since september when i pulled trans to swap in a five speed. also replaced distributor. Now the work is done and after trying to start found no fuel getting to carb, can't hear pump running, tested and no power.

I have poor info, the repair manual is useless, the electrical diagrams don't match my car. I've learned the pump starts based on the ignition switch position or alternator spinning after it starts. Also found a rev sensor under dash but it seems I'm having trouble tracing wires and matching the colors thru out vehicle. What i did find was one wire with same colors as pump pigtail going to regulator and a pair of wires matching the other wire on pump connecting to rev sensor. So confused, and without good electrical diagrams. Any ideas

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I also checked for spark, cause I didn't  get any kick when trying to start with starter fluid. Don't seem to have any spark at the plug. I know I changed the dirty but was very careful to replace as it came out, with motor lined up on tic. I would still get a spark if I was 180 off, it would just fire on exhaust stroke instead of compression stroke, maybe get some popping out the exhaust. Is my thinking right here, maybe this problem is linked to my not have power to fuel pump. I also checked new pump, it does work.

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No spark = no fuel pumping.

 

Work out the spark first then go from there... It's better to have spark and no fuel when trying to set something started IMO.

 

With the replacement dizzy, points or module? If module replace it. If points make sure it's wired in properly and the gap is adjusted properly too. You may need a different coil for the two setups, I can't remember this exactly as it's been ages since I've played with the two systems.

 

All the best

 

Bennie

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first step is to determine if you have spark signal getting to rev sensor.  You may have messed something up replacing the disty.

 

While cranking, does the tach needle jump a bit?

No bouncing needle tach while cranking

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Ok new information from my end.

 

Last week my brumby stopped dead in its tracks.  Turned out the module in the dizzy died - because the coil let go.  So I killed a good module in the process of working out that the coil was bad.

 

I also ran a jumper wire in the plug for the rev sensor unit that triggers the fuel pump.  I guessed which wires ran the pump, for mine it was the two thickest wires, both black wires, one with a white trace.  This made my fuel pump run whenever ignition was on.

 

Before I got my brumby running again I reversed this mod as it confirmed that the fuel pump was good.

 

New coil then new module (2nd hand one now that I killed the new one :angry:), fired up first kick and hasn't looked back B)

 

Cheers


Bennie

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I'm still stumped. I check for spark directly from coil and have none, I found 12 volts from ignition to coil, I did electrical checks on coil and felt it was bad with readings I was getting,(can't tell what manufacturer it is) and my meter tends to jump around making it difficult to read, replaced it and still no spark. Can't check module in disty so put one from old disty into new disty and still no spark. I had a resistor go bad once, but it would just shut down car and once it cooled car would run again, I don't know what else the is to replace, any help?

 

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Take the cap of the disty and crank the engine.  Watch that the rotor turns.

 

If it doesn't turn, the keyway that hold the worm gear that drives the disty off the Cam may have stripped.

I'm getting no spark from the coil, would the dirty need to rotate to get spark from coil?

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Take the cap of the disty and crank the engine.  Watch that the rotor turns.

 

If it doesn't turn, the keyway that hold the worm gear that drives the disty off the Cam may have stripped.

Dirty is spinning with the engine

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Dirty... love it :P

 

The issue is either module or coil.

 

I don't think you should have a resistor in the system since it's got a module. Someone correct me if I'm wrong!

 

Cheers

 

Bennie

The resistor thats been there the whole time, I drove around my front yard before I put it on jacks last fall, is between the coil positive terminal and a ground on the head

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May I suggest you check the voltage regulator. At one time fuel pump would not run if the alternator was not energizing the regulator after started was disengaged This was to prevent the pump fro running after the engine died

 

Mike

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Haven't made any progress figuring out the no spark problem, checked every suggestion and found nothing. Frustrated with manuals contradictory into, but I'm working on another problem. I put 5 speed tranny in and an trying to attach wiring connectors. There were two switches on the old four speed and the newer five speed has three switches. I've checked continuity on all three switches and all show no change in continuity when tranny is placed in reverse or 4 hi/low. According to the manual I should have a backup light switch on left side of case and a neutral start switch right next to it or on the clutch pedal. I have no neutral start switch in either location, the backup light switch, if thats what it is, shows no change in continuity if tranny is placed i reverse. The other two switches are both near top of case and seem to have something to do with 4x4 function, due to location? Also with no wires connected to tranny the FWD light is on. Can anybody clarify what switch is which,  Thanks

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I have good news, I solved the tranny wiring problem and that led me to find out that now I have a spark and it started right up, still not sure what I did but after hooking wires to two sensors on tranny 

, when turned on the key i noticed the fuel pump running. Anyway now it running and thanks for all your help!

 

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I have good news, I solved the tranny wiring problem and that led me to find out that now I have a spark and it started right up, still not sure what I did but after hooking wires to two sensors on tranny 

, when turned on the key i noticed the fuel pump running. Anyway now it running and thanks for all your help!

Figured out what the problem was. I finally took it for a drive and didn't make it down the front drive, found that when i connected the ignition module I placed the female end of wire on the male end, but had the male post between the rubber boot and connector on female side.

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