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1981 Brat Starts But Does Not Idle


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So My brother and I have been trying to get my Brat running

 

It's a 1981 4wd EA81 with the dual range.  We can start the car but when you let go of the ignition switch the motor just dies.  Before we swapped some of the ignition wires around the car would start and run but you could not turn the motor off.  The brat would run until it ran out of gas.  We have a orange spark coming from the coil. 

 

"At the risk of repeating myself....

 

Put a test light on coil -.

It should light up and pulse w/cranking.

Light but no pulse = bad module

No light on coil - or + = power problem

No light on coil -,but,lights on coil + = bad coil

 

It is almost impossible to prevent an EA81 dizzy from turning."

 

fasdfasdfasdf

 

We ran these tests and were not able to get any readings, from any of the leads.  I used a tested ground above the coil and ran the test with the ignition switch in the off, on, and acc positions. 

Edited by brat69
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Its been so long since ive touched the older ignitions. Pretty sure during cranking full battery voltage is put too the coil and in run/on the voltage is run through a ballast resistor befor the coil. So:

Your ballast resistor is bad

You have a wiring problem

Your ign switch is bad.

The spark from your coil should be loud and blue.

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Its been so long since ive touched the older ignitions. Pretty sure during cranking full battery voltage is put too the coil and in run/on the voltage is run through a ballast resistor befor the coil. So:

Your ballast resistor is bad

You have a wiring problem

Your ign switch is bad.

The spark from your coil should be loud and blue.

So do you believe its a combination of all these problems or just one or the other?

 

Do you know where the ballast resistor is located? 

 

How can you test the ignition switch? 

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Start with a voltage check at the coil there should be about 7 volts with ignition in the run position and 12 volts when in the start position.

The Ballast resistor is usually a long rectangular ceramic item mounted on or near the coil that has a wire coil winding tucked inside it much like a electric radiator element winding and operates the same way shedding voltage via heating up the wire element.

 

The Idea is that you run a Coil designed to nominally operate on 7 volts and the start position of the ignition switch bypasses the normal coil power for run mode that goes through the ballast resistor and gives 7 volts to supply 12 volts in cranking start mode for a stronger spark when cranking.

 

Seems your 7 volt circuit is either not supplying power or hooked up wrong, Get a multi meter and check voltage supply at all the wires near the coil and ballast both cranking power and run power should supply 12 volts at the wiring and when hooked up you should see 7 volts out of the ballast resistor that goes to coil positive terminal as well as a straight 12 volt supply from the wire powered up only when cranking that also goes to coil positive terminal.

 

Negative connections are to distributor and tachometer only obviously they seem to be OK as it does start

 

If you measure the power as explained above and both 12 volt supplies are found in the wiring at both crank and run modes then the ignition switch is OK if only one 12 volt can be found look at the ignition switch wiring 

Edited by coxy
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I don`t think 81 BRATS have a ballast resistor.

Even if they did,coil voltage would be 12 volts regardless of key position(except off) with the engine stopped.

(there is no current flowing thru the coil w/engine stopped and therefore NO voltage drop across the resistor)

 

I think the engine would not stop because a faulty voltage regulator is backfeeding voltage to the coil w/the key off.

 

Test the switch by seeing if it passes/doesn`t pass voltage/current as required.

 

Spark colour is irrelevant.

Orange just means there is some sodium present.

Test spark strength by seeing how long of a gap it will jump.

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Start with a voltage check at the coil there should be about 7 volts with ignition in the run position and 12 volts when in the start position.

The Ballast resistor is usually a long rectangular ceramic item mounted on or near the coil that has a wire coil winding tucked inside it much like a electric radiator element winding and operates the same way shedding voltage via heating up the wire element.

 

The Idea is that you run a Coil designed to nominally operate on 7 volts and the start position of the ignition switch bypasses the normal coil power for run mode that goes through the ballast resistor and gives 7 volts to supply 12 volts in cranking start mode for a stronger spark when cranking.

 

Seems your 7 volt circuit is either not supplying power or hooked up wrong, Get a multi meter and check voltage supply at all the wires near the coil and ballast both cranking power and run power should supply 12 volts at the wiring and when hooked up you should see 7 volts out of the ballast resistor that goes to coil positive terminal as well as a straight 12 volt supply from the wire powered up only when cranking that also goes to coil positive terminal.

 

Negative connections are to distributor and tachometer only obviously they seem to be OK as it does start

 

If you measure the power as explained above and both 12 volt supplies are found in the wiring at both crank and run modes then the ignition switch is OK if only one 12 volt can be found look at the ignition switch wiring 

I don't ever recall seeing a resistor, though in the Haynes manual it shows one in the diagrams.  We picked one up and are trying to figure out how to wire it in.

We tested the wires going into the coil(2 from disty, 2 from ig?) and the test light does not go on with the tool grounded.  But if I hook up the test light to the battery + one of the wires will light up from the ig.  There is a blue wire in the round harness that goes to the metal chunk that is constantly hot.  

 

I don`t think 81 BRATS have a ballast resistor.

Even if they did,coil voltage would be 12 volts regardless of key position(except off) with the engine stopped.

(there is no current flowing thru the coil w/engine stopped and therefore NO voltage drop across the resistor)

 

I think the engine would not stop because a faulty voltage regulator is backfeeding voltage to the coil w/the key off.

 

Test the switch by seeing if it passes/doesn`t pass voltage/current as required.

 

Spark colour is irrelevant.

Orange just means there is some sodium present.

Test spark strength by seeing how long of a gap it will jump.

Okay, how do do we go about testing the switch? 

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I fear were confusing the O.P.

 

 

So do you believe its a combination of all these problems or just one or the other?

Im sorry this was meant to be a trouble tree of things to test for. Doubt it would be all of them, just one.

You probably have a hitachi disty. Since you say there is 2 wires going from the disty directly to the coil Ide say he doesnt have the old style external module. Hence no ballast resistor. The manual you have shows the resistor because its generic and  showing the Nippondenso setup.

Brat69, Do you know if your ignition module is external or under your disty cap?

I do not have a wiring diagram for your 81 so I cannot offer any specs on where the system gets its power. 

 

 

Before we swapped some of the ignition wires around the car would start and run

What exactly did you "swap around"?

With the switch in the "run/on" position does anything else work? Have you checked your fuses?

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I fear were confusing the O.P.

This is true.

 

I believe it is the internal ignition module. I took off the disty rotor and tested it for shaft play; there was none. 

 

IMG_2887.jpg

IMG_2888.jpg

 

We dont remember but, I think we moved the Black wire to the "ig" spot on the switch. The car would turn on then turn off.  Then we left and it stopped working, then we ended up moving to something else then along the way, I found a blown fuse (the fourth one from the bottom 25amps).  

 

There are 4 wires coming from the ignition harness black, blue, white, and black/yellow. We know that the white goes to the battery and that the black/yellow goes to the starter.   The other two, we have no idea, so if you have an idea, please let us know! 

 

edit: ran the test again, and now we are not getting any power to the coil.  or we have a "power problem"

Edited by brat69
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Module is under the cap.

 

http://www.ultimatesubaru.org/forum/topic/147150-brat-electrical-qs/

 

Sorry guys I had missed your old thread. You did not mention that mess. Since this has been stumping you for over a year now its time to get serious. Forget just getting it started. Even if you do get the car running how long will it run and how many other lil electric gremlins will you have? This needs some rewiring and you need some new tools and materials. Like an ohm meter, soldering iron, wire, heat shrink, etc. If you just need to get the car moved you could rig something up with a fuse and a switch.

Also your car is a 1st gen body style. Perhapse the historic guys will be of more help to you with diagrams an such.

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I put this in your other thread, (Post 21 I believe), but I'll put it here and add a bit more.

 

 

A = Accessory; Blue wire 

B = Battery +; White wire

I = Ignition; Black wire

S = Starter; Black/White wire (wire stripe may look Yellow from aging)

R = Resistor; Only used on Point/Condenser type distributors to feed full Battery voltage to distributor to aide starting. Engine then runs on 1/2 Battery voltage when key is released to "Run" position.

 

When Ignition switch is in the;

"Run" position, both the "I" and "A" contacts are fed power. This powers all of the vehicles electrical systems, minus the "Start Circuit".

 

"Accessory" position, only powers a few circuits. IE; heater fan, cigarette lighter, and a few others. Usually, dash gauges, alternator charge circuit, coil circuit are not powered.

 

"Start" position, feeds power to the starter solenoid and the "I" for the coil. Also feeds the "R" position, and is the, "ONLY TIME",, "R" is fed power.

 

I would seriously start looking for a replacement wiring harness for that BRAT. It has been hacked way to much. You will be chasing wiring issues for a long time.

 

 

edit;

 

To add more info...

 

If you have the Black and Blue wires swapped around on the switch, you may not be feeding power where it needs to be fed during Starting. Same with switch in the Run position.

This may cause odd things to happen, like fuel pump not getting power when needed.

A carbureted vehicle will start and run, "IF",, there is fuel in the float bowl. But if the fuel is not being replenished, it will stall out due to lack of fuel.

Edited by TomRhere
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I put this in your other thread, Post 21 I believe), but Ill put it here and add a bit more.

 

 

A = Accessory; Blue wire 

B = Battery +; White wire

I = Ignition; Black wire

S = Starter; Black/White wire (wire stripe may look Yellow from aging)

R = Resistor; Only used on Point/Condenser type distributors to feed full Battery voltage to distributor to aide starting. Engine then runs on 1/2 Battery voltage when key is released to "Run" position.

 

When Ignition switch is in the;

"Run" position, both the "I" and "A" contacts are fed power. This powers all of the vehicles electrical systems, minus the "Start Circuit".

 

"Accessory" position, only powers a few circuits. IE; heater fan, cigarette lighter, and a few others. Usually, dash gauges, alternator charge circuit, coil circuit are not powered.

 

"Start" position, feeds power to the starter solenoid and the "I" for the coil. Also feeds the "R" position, and is the, "ONLY TIME",, "R" is fed power.

 

I would seriously start looking for a replacement wiring harness for that BRAT. It has been hacked way to much. You will be chasing wiring issues for a long time.

Thank you. We will hook it up after work and see what happens.  

 

My brother took off the disty cap and rotor.  He noticed that there were two ball bearings.  Where are these things from or did we drop them in by accident?

 

IMAG0468.jpg

 

 

 

Anyone have a wiring harness for sale!?

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I think we have to take the dash apart to figure out why we are not getting power to the coil.  Took a look at the ignition module  to see where the bb's go and found a few odd things. 

 

When we took off the reluctor, we found a total of 3 bb's and the spacers that go beneath the pick up coil and control unit were just laying around.  And the reluctor had a few small chips out of it. Whats weird is that the spacers are found on the turbo charged breakerless systems but our disty is the "late hitachi system."  In the Haynes manual, it shows a single piece spacer.  I don't know if its brass too or if it really makes a difference. But while the disty was slightly taken apart we did a resistance test.  And it failed. 

 

Could a bad pick up coil and unit be our problem? This wouldn't be part of the reason why the coil isn't getting power right? 

 

IMG_2890.jpg

IMG_2891.jpg

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thought of this post yesterday when starting a , or rather Willys new 78 Brumby. Here I am cranking away, trying to start the old girl...can't hear the fuel pump rattle away, poured some two stroke fuel down carb throat..good battery and know engine sounds right just won't run or fire - until, I noticed, it was running when I backed switch off th starter position to rest in IGN ON position far is this normal for GEN1's ? asks he in a GEN2 section !!

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  • 2 weeks later...

It lives!

 

The problem with the coil not getting power was a dirty/loose connection at the fuse and/or a cut in the line grounding out.  Cleaned and patched it up and cleared things up just a bit. 

 

Replaced the ignition control module because it didn't have any resistance to the disty body and took out the 3 ball bearings.  

 

Now we can start it and shut it off at will, for the most part!  The engine runs for a good 30 seconds before dying.  The idle sounds alright and seems to be running fine but then it just shuts off like it runs out of gas.  When I turn the key over to the start position we do not hear the fuel pump priming.  But how are we able to get the car started? If its running off of vacuum then wouldn't it just continue to keep sucking?   

 

Suggestions?

Edited by brat69
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Stock, the fuel pump on your car should be powered by the voltage regulator to prevent it from running if the engine is not turning. Without looking at a diagram I cannot tell you if that is bypassed during cranking (for priming). Again could be similar to what you have already been through. Wiring, the regulator or alternator. the voltage regulator could have easily been fried due to the current condition the harness is in. It may simply not be hooked up correctly. Maybe the pump could be intermittent or poorly grounded. Once this is is solved will the gremlins continue?

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Stock, the fuel pump on your car should be powered by the voltage regulator to prevent it from running if the engine is not turning. Without looking at a diagram I cannot tell you if that is bypassed during cranking (for priming). Again could be similar to what you have already been through. Wiring, the regulator or alternator. the voltage regulator could have easily been fried due to the current condition the harness is in. It may simply not be hooked up correctly. Maybe the pump could be intermittent or poorly grounded. Once this is is solved will the gremlins continue

 

Stock, the fuel pump on your car should be powered by the voltage regulator to prevent it from running if the engine is not turning. Without looking at a diagram I cannot tell you if that is bypassed during cranking (for priming). Again could be similar to what you have already been through. Wiring, the regulator or alternator. the voltage regulator could have easily been fried due to the current condition the harness is in. It may simply not be hooked up correctly. Maybe the pump could be intermittent or poorly grounded. Once this is is solved will the gremlins continue?

I will take a look.  Its getting power.  Not sure if the filter or the lines are clogged.  But once this is fixed there are a few gremlins to be smashed.  Turn signal switch, hazard switch, we don't even know where they go, the horn/steering wheel, marker lights, tail gate handle, steering knuckle(currently a 3wd or 1wd brat), few tiny bits of rust, resealing the windshield.  im hoping to be able to drive it and not be towed around it, for once. 

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you should be able to start any old carby engine without a fuel pump - so long as fuel in the carby bowl is at the correct level. It should be able to start, run and accelerate for a small time before fuel runs through and depletes. IF it was efi, can still start without the pump operating, so long as the line pressure remains from last operating moment, and then as pressure drops off engine will falter and cut out.

 

When you say in first post that engine would not stop when switched off - you don't say how many revs it was idling at - incorrect speed , like info, can produce bum steers

Edited by jono
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you should be able to start any old carby engine without a fuel pump - so long as fuel in the carby bowl is at the correct level. It should be able to start, run and accelerate for a small time before fuel runs through and depletes. IF it was efi, can still start without the pump operating, so long as the line pressure remains from last operating moment, and then as pressure drops off engine will falter and cut out.

 

When you say in first post that engine would not stop when switched off - you don't say how many revs it was idling at - incorrect speed , like info, can produce bum steers

We were too excited to take note of idle speeds when it engine would continue to run.  We'll take note of it next time.  Might take a look at the carb to see if it needs a cleaning/rebuilding.  The air cleaner was filled with a bunch of gunk  and some loose debris. 

Edited by brat69
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  • 2 weeks later...

I'm brat69 brother and I'm trying to finish her up for him. Right now I'm stuck on why the gas pump is not staying on when the car is running. There's no relay I can find. The voltage regulator works. And the lines are not clogged. So I'm thinking about running a hot from the battery to the pump with a toggle switch to turn on/off. I would love to keep it factory. But has anyone Tryed this and anything else I should check before doing this?

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If the voltage regulator works and you have a wiring diagram then I would guess you could run a jumper wire from the regulator to the pump. I dont have a diagram handy so I will not be giving you specifics. If you really wanted to bypass the stock setup then some means of keeping the pump from running while the engine isnt should be used. This is not just for safety, and anyone equipped to properly install such a setup would probably simply repair the factory wiring. I dont know if you guys are equipped to properly tackle this. The wiring on that car is in an unfortunate state, and needs some reworking. If you choose to simply run a switch and wire all the way to the fuel pump, it would be best to use a keyed source and obviously a fuse. After winning the fuel pump battle, I fear other issues will come up/continue. I have played with vehicles that had a small fire or rat infestation and it requires more than a test light, but connectors, and wire nuts. Im not making fun of you guys, simply feeling your pain. Befor you rig it Ide try to figure out whats going on with the wire from the regulator feeding the pump.

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I would love to keep it stock. So I started to follow the wires back again from the regulator to tge fuse box then from there to the pump. I found at least 7 wires fully exposed and touching one another. Going to pick up wire today and patch it up. Keeping my fingers crossed this is the reason the pump won't stay on. And thanks for all the info guys n gals really helpful!!!

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Quick update: fixed the exposed wires. Replaced the broken electric choke with manual choke. Put on a clear fuel line to carb to see if I lose fuel and to see if the pump was lacking pressure by sight.

So this morning I started the brat. When I cranked it I seen the fuel go to tge carb very quickly and stayed thereso I assume there's no leak. But with the choke closed it idel at 2k rmp. Is that normal? As it warms up I can half choke and it'll drop to 1k rpm. I would have let it run but the exhaust pipe isn't connected so the smoke in the garage was getting dangerous. So I think I'll just push it out tonight and start it.

Also if the pump isn't running would the fuel from the line in just drain? Before when I took it off it was dry not even a drip unless we had it just running. Thanks in advance!

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you should be able to start any old carby engine without a fuel pump - so long as fuel in the carby bowl is at the correct level. It should be able to start, run and accelerate for a small time before fuel runs through and depletes. IF it was efi, can still start without the pump operating, so long as the line pressure remains from last operating moment, and then as pressure drops off engine will falter and cut out.

 

When you say in first post that engine would not stop when switched off - you don't say how many revs it was idling at - incorrect speed , like info, can produce bum steers

 

Before with a broken choke it would idle at 100rpm. Put manual choke in now it sits at 2k rmp and jumps down to 1k rpm after warming up and I put it on half choke. Suggestions or is this normal rpm?

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