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With the reference screw missing, that presents a real challenge to get the injection pump calibrated correctly, since everything depends on the "zero" of the reference screw. In order to to a proper technical calibration of the reference screw, the pump has to be removed from the engine and put on a test bench.

That said. Here's what we're going to do from a practical, albeit not perfect standpoint. I'm going to send you a new machine screw that is cut so that when screwed into the casting boss, and snugged enough to hold, that it sticks out .125 - .130" from the boss, which is right at what the several pumps that I have run at. That will be very close to correct calibration and permit a rational approach to tuning, vice what you're doing now which is "screwing with it until it runs." Screwing with it till it runs has been a favorite with owners for years, but rarely results in an acceptably running engine. You will be surprised at how responsive and fuel efficient a properly tuned Spica system is.

When you get the screw install it with a bit of locktight. Do not use a washer or that will throw off the calibration. Just "snug" it into the boss, not "tighten" it. The boss is soft aluminium and the machine screw will bite into it if you use a lot of force.

Once the new reference screw is installed, then we can go through the lockstep tuning procedure and see what we get. I think that you're system is very badly setup and obviously completely out of proper tune. And, of course, the ignition system MUST be correctly tuned and timed BEFORE any attempt is made to tune the fuel injection system.

Send me a PM with a mailing address and I'll send the new reference screw to you.

With regards to the vent system leaking gas and oil, it sounds like it may be plugged up. Also, check your oil sump for gasoline. When Spica injection pump wear badly, they leak fuel past the barrels and plungers in the pump section and into the oil sump. I could be that your injection pump is completely shot, and in that case needs rebuilding by Wes Ingram. Look at the tech materials I sent you. Remove the Barometric Compensator and check for gasoline smell in the logic section of the injection pump.
 
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