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Discussion Starter #1
79 Spider that has been sitting about 6 months since I had a leaky fuel line. Finally got around to changing the lines, but it wont start. Confirmed fuel is getting to the Spica pump. However, fuel is not getting to the engine. It'll burn ether, but no fuel. Dry plugs and the four Spica ports, for lack of a better term, that you see when the air filter is off are dry as well. Any suggestions?
 

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When you re-connected the fuel lines did you install them correctly? The hose coming out of the front fuel filter should go to the rear fitting of the injection pump (no restrictor in the fitting) and the return line goes to the front fitting (with restrictor). If you hook them up backwards or have the restrictor fitting in the rear, the internal fuel gallery will not pressurize. Also, since the actual fuel line will be pressurized (but not the injection pump), the fuel low pressure light will be off indicating normal pressure. When you disconnect the return hose and put it in a bucket, does fuel flow out when the supply pump is running?

If that stuff is normal, loosen the fuel pipe fittings at the fuel injectors and crank the engine. Remove the spark plugs to lessen the load on the starter motor.
 

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Discussion Starter #3
When you re-connected the fuel lines did you install them correctly? The hose coming out of the front fuel filter should go to the rear fitting of the injection pump (no restrictor in the fitting) and the return line goes to the front fitting (with restrictor). If you hook them up backwards or have the restrictor fitting in the rear, the internal fuel gallery will not pressurize. Also, since the actual fuel line will be pressurized (but not the injection pump), the fuel low pressure light will be off indicating normal pressure. When you disconnect the return hose and put it in a bucket, does fuel flow out when the supply pump is running?

If that stuff is normal, loosen the fuel pipe fittings at the fuel injectors and crank the engine. Remove the spark plugs to lessen the load on the starter motor.
All is together properly. We did not unhook the return line, only the supply line and fuel WAS flowing out of it. So if we unhook the return line, will that tell us if fuel is running through the pump?

Also,if we loosen the fuel pipe fittings at the injectors and there is fuel, does that suggest the injectors may be plugged?

One last question, if the cold start solenoid is bad, might that completely cut off the fuel supply and kill the entire system?

Thanks!
 

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All is together properly. We did not unhook the return line, only the supply line and fuel WAS flowing out of it. So if we unhook the return line, will that tell us if fuel is running through the pump?
Yes

Also,if we loosen the fuel pipe fittings at the injectors and there is fuel, does that suggest the injectors may be plugged?
Yes, it will tell you that the Spica is producing pressure and delivering fuel up to the injectors. But I never heard all four injectors to be plugged at the same time.

One last question, if the cold start solenoid is bad, might that completely cut off the fuel supply and kill the entire system?

Thanks!
No not the cold start solenoid, but that could happen with a no working fuel cut off solenoid, or a defective and stuck mircroswitch. The FCS is the front most solenoid on your pump . Just remove the cable on top of it and put some insolation around the cable to avoid electric hazard. With a defective mircroswitch you should have permanent electricety on this cable once the ignition is on. Just try to start the engine without that cable attached.

There is on other thing which can prevent fuel going from the spica to the engine. A broken retainer spring at the barometic sensor will lean out the mixture completely.
Just download the beautiful guides from Roadtrip here:

http://www.alfabb.com/bb/forums/carburetors-fuel-injection-air-intake/335530-spica-technical-guides.html

Good luck and salutations from the Baltic sea

Bernhard
 

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Discussion Starter #5 (Edited)
Thanks, Bernhard! So, the return line is producing fuel, so that is fine. We pulled the FCS (which is what I meant btw) and it still wouldnt start on its own. It DID start with ether and then started running on gas. Clearly responded to throttle input. After it ran for a minute or two we hooked the FCS back up and it died within a few seconds. Unhooked the FCS and it wouldnt start on its own. Added ether and it started, but a bit roughly and died. Also, retainer spring is fine. Small pool of oil at the bottom below the spring that does not have a strong gas smell. Thoughts?

Forgot to check the injectors, but since it clearly started running on gas, I assume the injectors are not a problem.
 

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I agree with Bernhard.

1. Is the fuel pressure warning light working normally? Does it go OUT a few seconds after the ignition is switched ON? Does it stay out after the engine starts? If the fuel pressure is insufficient (<7 psi) the engine might actually run but very poorly and show signs of fuel starvation. It sounds to me from you're description that you have a fuel supply problem of low fuel pressure. Just because fuel comes out the hose, doesn't necessarily mean it's fine. You need at least 7 psi in the system to feed the injection pump barrels and plungers.

2. Confirm that the outlet fitting with the restrictor is in the front part of the injection pump.

3. Spica fuel injectors almost never clog because they operate at such high pressures (350-400 psi).

4. Disconnect the FCS wire and leave it off while you're troubleshooting.

5. The Cold Start Solenoid will not lean the mixture. It enriches the mixture and sometimes can cause starting problems if it is sticking. Anyway, to remove it as a troublemaker, disconnect the wire and try a start.

6. Hook a test light to the FCS feed wire and see if it's getting constant current. Sometimes if the feed wires to the microswitch get rubbed raw, they can short and send a constant fuel shutoff signal to the FCS.

Try another start and get it running. Are you sure that the ignition timing is correct?

If unable to start, remove the Barometric Compensator (triangular plate on the top of the logic section). when you do this, it will just lift out of the body of the injection pump. Be careful not to damage it. DO NOT move the throttle while it is out of the pump. Look down into the forward section of the pump and confirm that the small vertical spring is attached at both the top and the bottom. It's ok to poke it a little to be sure.
 

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Discussion Starter #7
I agree with Bernhard.

1. Is the fuel pressure warning light working normally? Does it go OUT a few seconds after the ignition is switched ON? Does it stay out after the engine starts? If the fuel pressure is insufficient (<7 psi) the engine might actually run but very poorly and show signs of fuel starvation. It sounds to me from you're description that you have a fuel supply problem of low fuel pressure. Just because fuel comes out the hose, doesn't necessarily mean it's fine. You need at least 7 psi in the system to feed the injection pump barrels and plungers.

2. Confirm that the outlet fitting with the restrictor is in the front part of the injection pump.

3. Spica fuel injectors almost never clog because they operate at such high pressures (350-400 psi).

4. Disconnect the FCS wire and leave it off while you're troubleshooting.

5. The Cold Start Solenoid will not lean the mixture. It enriches the mixture and sometimes can cause starting problems if it is sticking. Anyway, to remove it as a troublemaker, disconnect the wire and try a start.

6. Hook a test light to the FCS feed wire and see if it's getting constant current. Sometimes if the feed wires to the microswitch get rubbed raw, they can short and send a constant fuel shutoff signal to the FCS.

Try another start and get it running. Are you sure that the ignition timing is correct?

If unable to start, remove the Barometric Compensator (triangular plate on the top of the logic section). when you do this, it will just lift out of the body of the injection pump. Be careful not to damage it. DO NOT move the throttle while it is out of the pump. Look down into the forward section of the pump and confirm that the small vertical spring is attached at both the top and the bottom. It's ok to poke it a little to be sure.
1) I dont think it has worked in years. My dad bought the car new and said he does not recall it working in quite some time. So, you may be right.

2) We are good there.

3) Understood

4) 10-4

5) Will do.
6) Will do.
 

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Discussion Starter #8 (Edited)
So, CSS unhooked with FCS unhooked. No joy. CSS hooked back up and FCS unhooked. I coughed and sputtered a few times like it wanted to start, but no joy. Makes me think you may be correct with the fuel pressure. Does it make sense to think if its making just shy of enough that a little may get there, but not enough to fire and keep running?

How would pressure be diagnosed? In line gauge or just buy a new pump since the pumps are original? Which pumps?

Also, when we checked the amount of fuel that came out, it had to be an ounce in less than 2 seconds. Although I suspect that doesnt tell us anything.
 

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Read the Fuel Supply System Guide.

Until the ignition system and fuel supply system is good, you're wasting your time trying to start the engine. And in fact, may be damaging your injection pump by pumping a lot of particulate matter into it. The Spica pump section is very dependent on clean fuel . . . hence the TWO fuel filters.

If you have an original fuel supply pump, I can almost guarantee you that it's unserviceable, especially if it sat derelict for years. I would not trust an old OEM pump. In fact the entire fuel system, tank to engine and back needs to be inspected and cleaned. One of the surest ways to wreck a Spica system is to leave it derelict, although 6 months isn't too bad . . . rusty fuel tanks, clogged fuel filters, gummed/varnished up fuel supply pumps, front fuel filters/pressure relief valves, and injection pumps.

You can use an inline gauge (between the front fuel filter and the injection pump). With the engine off you'll get a steady reading. With the engine running, unless the fuel pressure gauge is dampened, you'll likely see wild pressure fluctuations due to the pumping action of injection pump itself. Depending on the gauge, you might be able to make out a "mean" reading. The salient fact is that the low pressure warning light needs to be out, indicating >7 psi. Normally, I like to see 10 psi with the fuel supply pump running on only battery (12v) and 13-15 psi with the engine running and alternator supplying around 14 volts. The supply pump is VERY sensitive to voltage in how much pressure it puts out. That's why it's very important to have excellent electrical connections to it (both power and ground connections) with no line voltage loss.
 

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Discussion Starter #10 (Edited)
I agree with Bernhard.

1. Is the fuel pressure warning light working normally? Does it go OUT a few seconds after the ignition is switched ON? Does it stay out after the engine starts? If the fuel pressure is insufficient (<7 psi) the engine might actually run but very poorly and show signs of fuel starvation. It sounds to me from you're description that you have a fuel supply problem of low fuel pressure. Just because fuel comes out the hose, doesn't necessarily mean it's fine. You need at least 7 psi in the system to feed the injection pump barrels and plungers.

2. Confirm that the outlet fitting with the restrictor is in the front part of the injection pump.

3. Spica fuel injectors almost never clog because they operate at such high pressures (350-400 psi).

4. Disconnect the FCS wire and leave it off while you're troubleshooting.

5. The Cold Start Solenoid will not lean the mixture. It enriches the mixture and sometimes can cause starting problems if it is sticking. Anyway, to remove it as a troublemaker, disconnect the wire and try a start.

6. Hook a test light to the FCS feed wire and see if it's getting constant current. Sometimes if the feed wires to the microswitch get rubbed raw, they can short and send a constant fuel shutoff signal to the FCS.

Try another start and get it running. Are you sure that the ignition timing is correct?

If unable to start, remove the Barometric Compensator (triangular plate on the top of the logic section). when you do this, it will just lift out of the body of the injection pump. Be careful not to damage it. DO NOT move the throttle while it is out of the pump. Look down into the forward section of the pump and confirm that the small vertical spring is attached at both the top and the bottom. It's ok to poke it a little to be sure.
Read the Fuel Supply System Guide.

Until the ignition system and fuel supply system is good, you're wasting your time trying to start the engine. And in fact, may be damaging your injection pump by pumping a lot of particulate matter into it. The Spica pump section is very dependent on clean fuel . . . hence the TWO fuel filters.

If you have an original fuel supply pump, I can almost guarantee you that it's unserviceable, especially if it sat derelict for years. In fact the entire fuel system, tank to engine and back needs to be inspected and cleaned. One of the surest ways to wreck a Spica system is to leave it derelict . . . rusty fuel tanks, clogged fuel filters, gummed/varnished up fuel supply pumps, front fuel filters/pressure relief valves, and injection pumps.
That is what I was worried about. Ran fine until the fuel line developed the leak. Not sure how I would get it to Nasko in Portland since it doesnt run. Im thinking Ill just order new pumps and filters, install and see where we are from there. Can only improve things since the pumps are original.

Are these the ones I need? Happy to order elsewhere if there is an Alfabb supporting advertiser.

https://www.centerlinealfa.com/fuel-system/1181

https://www.centerlinealfa.com/store/1175

https://www.centerlinealfa.com/fuel-system/1097

https://www.centerlinealfa.com/store/1099
 

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Discussion Starter #11
BTW - I took the low pressure sensor wire and applied it to a ground. No light. I then grounded a test light and applied it to the sensor. Test light did not light up.
 

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BTW - I took the low pressure sensor wire and applied it to a ground. No light. I then grounded a test light and applied it to the sensor. Test light did not light up.
You should not ground a test light, the sensor is switched on ground. So you need to apply the test light to a positive teminal and then test the low pressure switch it should light up with the ignition turned on and should go out after a couple of seconds, as soon as there is enough pressure in the fuel system.

And John is right, and I did post the link in my first post, you should read the:

http://www.alfabb.com/bb/forums/attachments/carburetors-fuel-injection-air-intake/586562d1405965707-spica-technical-guides-spica-fuel-supply-diagnostic-guide-ver-8-final-aug-13.pdf

Everything is explained there.

The pumps and filters do look right to me.

All the best and salutations from the Baltic Sea

Bernhard
 

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You should not ground a test light, the sensor is switched on ground. So you need to apply the test light to a positive teminal and then test the low pressure switch it should light up with the ignition turned on and should go out after a couple of seconds, as soon as there is enough pressure in the fuel system.

Bernhard
Ah! OK. Since the sensor works off a ground, the way the light works is opposite in a sense. Put the light on a live wire and the ground on the sensor.
 

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Ah! OK. Since the sensor works off a ground, the way the light works is opposite in a sense. Put the Testlight on a live wire and the ground on the sensor.
Using a testlight you will have to use on one side a live wire and the groundwire is the Fuelpressure sending switch.

Sorry for my poor english.

Bernhard
 

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Using a testlight you will have to use on one side a live wire and the groundwire is the Fuelpressure sending switch.

Sorry for my poor english.

Bernhard
Your english was perfect! I checked it as you said and the light lit up off the sensor. So, probably just a bulb. Gotta figure out how to get it out. Hoping I dont have to take the dash apart.

Also, the light turned off after approx 8 seconds which leads me to believe the sensor thinks pressure is ok. COnfirmed it three times.

Thanks for the help!
 

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8 seconds is pretty long for the fuel low pressure light to go out. I'd like to see a lot more like 2 seconds. I think you got a clogged system or a weak fuel supply pump or bad wiring to the pump. If you have an in-tank boost pump test it. You MAY deadhead check the in tank boost pump, however never deadhead the main pump. It puts out too much pressure if deadheaded.
 

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8 seconds is far to long.
Even with my car sitting for three month in a row it will be only a blimb and the light will go out.
Go for the filters first and second for the pumps.

Good luck

Bernhard

Edit: Every time when I change the rear fuel filter I will cut the old one in half to see wether or how much dirt it in the filter. Good control for a bad or dirty fuel tank as well
 

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8 seconds is far to long.
Even with my car sitting for three month in a row it will be only a blimb and the light will go out.
Go for the filters first and second for the pumps.

Good luck

Bernhard

Edit: Every time when I change the rear fuel filter I will cut the old one in half to see wether or how much dirt it in the filter. Good control for a bad or dirty fuel tank as well
Picked up a filter about 45 minutes ago. Will install tonight and report back. Thanks!
 

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Discussion Starter #19
OK. Im going to fall on my sword here in an attempt to continue educating the board. Anyhow, last night I noticed when I checked the fuel pressure light that the red low fuel indicator was lit. Added 5 gallons, primed the fuel pump and it fired right up. Yes, Im an idiot. Had filled the tank prior to the leaky line and drove 40 miles. I had NO idea all fuel had leaked out. Probably lucky it didnt ignite on the exhaust while on the freeway as it had to dump at least 6-8 gallons.

Anyhow, I am still going to replace the filters and pumps. Thanks to all that responded. And to those who have similar questions, make sure you have enough fuel to make the pressure you need.
 
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