Re: Spica/Marelli engine lost power

[Hirsch <Catenary@domain.elided>]

Costel Vasiliu writes:

> Crank the engine, starts beautifully! Yee-haaa! :-) Let it
> warm up for a while at fast idle. When it went back to normal
> idle, I connect the fuel cut off solenoid wire. Guess what?
> The engine stops right away!

I had this happen to me once. Problem turned out to be the
fuel cutoff solenoid (FCS) microswitch. Here's the story:
 =

So I'm getting the '78 Spider ready for our local Spring
Alfa event in Washington Missouri. Part of the process
includes spraying the engine with degreaser and washing
it off with lots of water...

Next morning, the car starts right up and runs well for
about 30 miles. Then a stumble that lasts for about three
seconds. After that the car would alternate between running
well and stalling. The car seemed to be OK as long as I
accelerated, but on just holding the gas pedal steady,
the car would lose power. After about four miles of battling
the car, I decided to pull off the road and see if I could
find anything wrong.

When I pulled off the road and let off the gas the car died
immediately and would not restart. Since I had been fighting
with my Spica pump for the last month or two, I suspected that
it was the problem. To make a long story short (too late for
that!) I did manage to get the car running again by unscrewing
the fuel-cutoff solenoid a few turns to richen the mixture. I
then limped home.

A few days later, when I checked the Spica pump at home, I
found that the fuel-cutoff solenoid was constantly being
supplied 12v by the micro switch and that this was causing
the fuel mixture to be much too lean. So once again the Spica
pump would have to come off. One and a half hour later, the
pump was on the bench. When the micro switch cover was
removed, I noticed a stream of water coming from the micro
switch compartment! Apparently, when I washed the engine,
water had gotten into the micro switch compartment. Checking
the cover, I noticed that the seal was poor. Consequently,
water could get into the compartment and did not drain out.

I took apart the microswitch (it comes apart quite easily)
and cleaned out the coagulated crud (old grease that had
hardened?). After the switch was clean and the internal
spring made to work, I put in a little grease and reassembled
the switch. The switch was then put back on the pump and
adjusted for 1mm clearance as per the AROC Spica Tech Notes
book. On replacing the cover, I used some silicone RTV
gasket sealer to try to discourage water from entry in
the future. (Before reassembly, make sure that the rubber seal
in the microswitch compartment is is good condition. If it's
not, replace the seal. On another occassion I've had this
seal crack and as a result I lost a lot of oil.)

Moral: Don't use much water around the Spica pump when
you're washing the engine! And, if you're in limp-home
mode, disconnect the wire to the cutoff solenoid.
 =

Rich Hirsch
'87 Milano
'78 Spider
'67 Duetto
'66 Sprint GTV
Editor, i Saluti, St Louis AROC
Website: http://www.catenary.com/isaluti

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