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Discussion Starter · #1 ·
Hello all,
Title pretty much says it all. I have:

Flushed the fuel tank.
Replaced all rubber fuel hoses from the tank to the FI pump.
Replaced the fuel pump.
Replaced both fuel filters.
Replaced the low fuel pressure sensor.
Replaced both air filters.
Replaced the distributor cap.
Replaced the rotor.
Triple-checked the connection of spark plug wires.

I didn’t replace the points or redo the timing — too lazy at this point. It was running fine until the low fuel pressure came on, hence my replacing pretty much everything that could be the culprit. I also tried with the CS solenoid disconnected— no joy.

At this point I’m at my wits end. Any words of wisdom…?

Many thanks,
Bob

PS
Is it possible to attach a video clip here?
 

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Have you verified the timing on the SPICA ? When I got mine I spent a bunch of hours trying to start her until a friend told me to never assume the guy before you did anything right. The timing on the pump was 180' off. he timed it off cylinder 1 IT TIMES OFF #4 ( SNEAKY ITALIANS)
 

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I would:
1) verify ignition timing and pump timing.
2) ensure CS if functioning properly and not stuck - may be too much fuel (over rich mixture) on start up.
3) verify TA and cold gap
 
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I'd do the following, assuming everything was running great, you got FP light on and motor died, then you did all the above
a. Remove the fuel inlet hose from SPICA, put the hose in a bucket, and turn the ign switch to RUN. See if you get a nice clean steady stream of gas out
b. Use your air compressor and blow out (gently but firmly) the return line from Spica back to the gas tank
c. Check your wiring, CSS wire goes to starter solenoid, FCS wire to micro switch
d. Check spica timing (it will usually run just fine if its 180 out
e. Check and recheck your distributor / plug wire order
f. Check to make sure the FCS is NOT energized (no 12V) when the car is trying to run
g. Failing all the above, back to basics -- compression test, etc
Make sure the long and short rods are connected on both ends!
 
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Discussion Starter · #7 ·
Have you verified the timing on the SPICA ? When I got mine I spent a bunch of hours trying to start her until a friend told me to never assume the guy before you did anything right. The timing on the pump was 180' off. he timed it off cylinder 1 IT TIMES OFF #4 ( SNEAKY ITALIANS)
If the timing is off by 180’, it wouldn’t have run fine for a year until now, no…?
 

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ive seen many spica cars with the timing 180 out that run just fine.
 

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You may have a kink in your fuel line or you may have a bad pump. Your low fuel pressure light is telling you that there's not enough fuel pressure. You may have enough fuel getting to the SPICA pump to start the car and get it to run for a short amount of time, but it seems to be starving for fuel.

Hook up a fuel pressure gauge to the hose coming from the fuel pump (best place is right before it goes to the SPICA pump. Have someone crank the starter and watch the pressure. When it's running, you'll most likely see the fuel pressure drop, right before it stalls.

Here's something to consider. We often confuse fuel pressure with fuel flow. For the car to run, you need both. With the motor not turning, your fuel pump should build pressure and the FP light turns off. As soon as fuel is being pumped thru the SPICA system, your fuel pressure may drop, because there isn't enough fuel being pumped to the SPICA pump. If this happens, you know the cause - low fuel flow to the SPICA pump. Now you have to find out why. Is it due to poor flow to the pump or a weak pump? The easiest is a visual check on the fuel lines from the tank to the pump. It could be restricted from a kink in the hose or even a twisted hose. It's also possible, but rare to have a hose delaminate from the inside and block some of the flow, but it's not likely to happen. To check flow to the pump, cut a section of hose and attach to the fuel pump inlet and to a test fuel tank (can make out of a container), but make sure gravity will feed the pump. If the car starts and runs, then there's a blockage from the tank to the pump. If the car starts and stalls, then you have a bad pump ... or you may have a blocked hose from the pump to the SPICA pump, but most likely it's okay.

Here's a easier way to check, but it's not as reliable. Open the gas cap and turn the key to run, but don't start the car. You should hear a strong flow of fuel returning to the gas tank. When you crank the starter and the car starts, keep listening and if the flow is the same, then the fuel pumping system is good and the problem is in the SPICA FI system or the spark. If you hear the fuel flow slowing and the FP light turns on, then you have a flow problem.

I hope this helps.
 

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Discussion Starter · #10 ·
So, I performed a few troubleshooting tasks today:

1. Applying 12v to the CSS yields the expectedm“click”. Ditto for the FCS.

2. I got this when I tested fuel flow:

1690223


This is what used to contain 5 liters of Croatia’s finest table wine. 😂. Just before entering the SPICA pump, this much fuel was pumped into the jug in about 40 seconds — I’d say about 2.5 liters.

1690227


This is a 9-ounce plastic cup. On the output return side of the front fuel filter, this much fuel was pumped in about 3 seconds.

1690229


This is a 1-liter container that was filled slightly more than halfway in about 10 seconds just before entry into the fuel tank on the return side.

In all cases, flow was strong. But what I DID NOT hear is the gurgling in the tank as fuel passed through the nipple on the top of the tank. My mistake — I supposed it’s possible that there is a blockage in that nipple. I need to check that tomorrow. Unfortunately, I don’t have access to a compressor to blow out any blockage. I’ll have to blow through a small piece of hose attached to the nipple.

I also tweeked the short linkage rod to get my best guess as to what “slightly open” butterflies means. Now when I start the car, it runs for about 5 seconds before stalling, but at a more normal (but rough) speed than the roaring idle from yesterday.

1690239


1690240


I pulled the plugs — sooty black, but not wet. I cleaned them, re-gapped them at .025”, reinstalled them, and started the car. Same behavior — stalls in 5 seconds.

Tomorrow I’ll check ignition timing and adjust as necessary…
 

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yeah check the return into the tank -- if its clogged, you will run rich -- once that checked and OK, its then onto mixture. For sure you are running very rich as evidenced by the plugs black and sooty
 
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yeah check the return into the tank -- if its clogged, you will run rich -- once that checked and OK, its then onto mixture. For sure you are running very rich as evidenced by the plugs black and sooty
Couldn't you just run the return line into the jug, and see if it keeps running? Maybe it takes 5 seconds for head pressure to exceed what the pump can provide?
 

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Yep but be careful… rather know if return in clogged, easy to Dx
 

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Discussion Starter · #14 ·
Problem solved… sorta.

First, the two hoses on the right-hand side of the front filter were crossed — input to return, return to input. 🤦‍♂️
Second, fiddling with the short linkage rod to reach that “just closed” sweet spot.
Third, the ignition timing was way off. Again, I fiddled with the distributor (which BTW wasn’t tightly bolted down and probably drifted to a position of bad timing over time) until I got the timing close enough to be able to start and keep it running.

Still, a few oddities, though. First, after starting, the revs surge very high for a few seconds and then drop to a more reasonable level. The idle is still higher than normal — how to tweak that? Second, should I be able to hear the gurgling of returned fuel with an ear at the filler neck? I don’t hear it. Third, I wanted to check the FCS for 9.5 full turns, but it’s REALLY tight… like 2 days of Blaster, slip-joint pliers, and vice grips — not a budge. I don’t think it’s ever been moved in its 50 years in existence. It looks like there’s an indexed nut at the base, but even a heavy-duty screwdriver and a BFH did nothing. HELP!

Almost there,
Bob

P.S.
I did want to confirm that there was no blockage at the fuel tank return nipple. Lacking a compressor, I MacGyver’ed a source of air pressure — a bicycle pump, a short piece of hose, and a copious amount of electrician tape to join them together. Worked like a charm — I heard lots of gurgling. 😁
 
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