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As I stated, the fuel pressure light will not go out until the main Spica pump is full of fuel. Until the body is full, the pressure in the feed line will be below the 7 psi necessary to trigger the switch for the light.

Since liquids are essentially incompressible, the instant the pump rotation starts, fuel will be sprayed from the injection nozzles. A short distance from the intake valve.

I’m well aware that the electric pump achieves somewhere around 10-12 psi prior to engine start and the system voltage comes up.

The question here is “when does fuel start coming out of the injectors?”. Assuming the pressure light is out, fuel starts spraying from the nozzles almost the instant that the injection pump starts rotating.

Fuel pumped out of Webers doesn’t get efficiently pulled into cylinder for at least a few rotations of the engine. The fuel is in the throat of the carb, and airflow is too low to move it forward very effectively.
 

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“when does fuel start coming out of the injectors?”. Assuming the pressure light is out, fuel starts spraying from the nozzles almost the instant that the injection pump starts rotating.

OK. We can make assumptions about the characteristic of the check valve to the hard lines based on experiences - which may differ.
 

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As an experiment, I deleted the check valve in inlet fuel line. If I did not wait until the low pressure light went out, cranking was longer. If I waited, starting was very quick.

With the check valve in the line, obtaining light-off was quicker than without.

All of this supports my contention that a Spica CAN produce a very quick start if all components are in place, working as intended, and adjusted correctly.
 

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I had a gear reduction starter installed- -it starts immediately- infinitely better than with std starter
 

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Discussion Starter #25
Hiya all, being completely satisfied with my love life, I suppose that I must be a SPICA man and will head off to the relevant sections of the forum immediately to begin learning the essentials of SPICA maintenance. My understanding from limited current knowledge is the first three things to check are (1) pump gap, (2) cold start solenoid operation, and (3) thermostatic actuator function. For good measure I will also check the fuel filter / pressure regulator and measure the fuel pressure delivered to the SPICA pump. Then report back with tears of either joy or despair.
 

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I would read up on the sequence of things to check first.
 

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Hi there, Spica is generally a start at the beginning of the setting process and go all the way through. It's not hard, could be a bit time consuming but almost always rewarding. So then 1) Ignition system is great. 2) Fuel supply system is great with correct operating low fuel pressure light. 3) Start spica system setting with checking throttle stops being correct and then go from there. Having a dummy thermostatic actuator is super handy. John Stewart used to have a stop checker tool but he isn't on the BB anymore but can probably be found. He may also have a manual for your car if you don't have the Wes Ingram book.

Cheers,
 

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Assuming everyone follows instructions, you don't crank a Spica car until the low pressure light goes out.

I'm learning something every time I read about Spica problems... I never knew I had to wait until the light goes out. I got my car without an owners manual, however, I have many shop manuals plus all the old Alfa magazines as well as special tools... but... when I start my car I need to slightly depress there throttle to open up the butterfly valves otherwise the engine doesn't rotate/start as easily. Then when it fires up, I can't depress the throttle until it warms up a bit. Once that happens it idles and runs beautifully. What do I need to do to improve the starting process?




Thus, the very instant you start cranking a healthy Spica system, high-pressure, largely atomized fuel is spraying directly at the back of the inlet valves. Having the CSS adjusted carefully is the key to getting reliable starts when either hot or cold. AND, the FCS needs to be adjusted for the correct mixture. If either or both are out, you'll get long starts.

My 77 Spider, which I think sat for most of 20 years, generally starts on the first piston stroke, unless the starter fails to engage, but that's a separate problem. It's rather astonishing, actually. Just bump the key and I've got a motor running.

This car was dealer maintained until the owner stopped driving in his late 80s, then it sat.
 

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You have described the published starting procedure.

Key on, wait for pressure light to go out.
Slightly depress pedal
Crank - hopefully gat a quick start
Sit there slightly opening throttle for about 5 - 10 seconds
Relax.

Cars that are perfectly on spec will generally start and idle without adding throttle. Still need to wait a few seconds after start before doing anything else.
 

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You have described the published starting procedure.

Key on, wait for pressure light to go out.
Slightly depress pedal
Crank - hopefully gat a quick start
Sit there slightly opening throttle for about 5 - 10 seconds
Relax.

Cars that are perfectly on spec will generally start and idle without adding throttle. Still need to wait a few seconds after start before doing anything else.
Thank you for this information. I'm committed to he SPICA as I have all the tools... but more importantly this engine pulls with a flat power curve, like a diesel. Strong and powerful. Of course adjusting the valve timing made a big difference.
 

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My experience tracks with most folks with properly set up Spica pumps: Touch the key and go. But, as stated previously there are a lot of variables and not just the pump. It is a good idea to work thru each system. It's fair to assume the pump and TA are good as they are recent Ingram rebuilds. Replace both fuel filters. Go thru the Spica set up procedure, check your ignition (cap, rotor, wires, plugs, coil, timing), do a compression and leak down test, check your cam timing.
 
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