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Help adjust the Spica BC

1K views 1 reply 1 participant last post by  bill in denver 
#1 ·
Hello I have an issue with the barometric (altitude) compensator on the Spica pump in my 69 Berlina.

Problem: The adjustment of the BC threaded stud where it goes thru the FCN lever has been lost and the car is very hard to start. (Dont ask how this happened but the lever and triangular housing sure is clean)

Engine is a 2L from a 74 spider; injection pump is a 237/1 (no fuel cut off solenoid) rebuilt by Ingram at some point.
I live in Denver at 5280 ft elevation (or altitude if you prefer).
The BC bellows looks normal, not extended.
The Compensator Link spring is intact

When I move the Compensator Link Arm, push back and move up or down the arm moves freely and retains the location it was put in but the ratcheting doesn’t feel really positive, I have not tried to count clicks down from top is this typically possible without putting eyeballs on the ratchet teeth? How do I know where to start do I move the arm all the way up then start counting down from there?

I have these two approaches in mind both leave to pump installed on the car: 1) adjust the length of the BC on the bench from end of pin to the bottom of the flange what should this length be for ~ 5000ft elevation? Set the link arm to just below this then rev/close throttle so the arm self adjusts.
2) Position the link arm to the 9th notch down (Is this correct for Denver?) then install and adjust the bellows so it just touches the link arm.

Will either of these procedures work? Can anyone fill in the blanks on length of the BC and number of clicks down for Denver?

Thanks in advance for any help!
Bill
 
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#2 ·
Well I ended up removing the pump. Evidently in my adjusting of the link arm I disengaged it from the serrated lever the hat spring rides on. Now I understand why later pumps have the set screw and lock nut on the end of the pump, its is a mechanical stop to prevent the BC link from disengaging.

I decided to cleanup the 74 spider Spica pump for installation. It looks clean inside, I'll keep my fingers crossed that its a good pump since the BC did smell gassy when I initially looked at it but it was sitting for a long time (years). I think I will replace the FCS microswitch. The one I removed looks like a Crouzet 83.132 which I think I can buy online for $6.43 or find in my local electronics store.
 
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