the reason my cold start didn't work

[Kjell]

I couldn't understand why the cold start
on my 73 GTV didn't work, so I started
to inspect the FI pump. The T/A had been
replaced for the PO by a "professional"
alfa mechanic. This person just slapped
in the rebuilt T/A and didn't bother with
checking the pump gap...... It turns out
that the new T/A was a newer unit and
should have had a shim installed under
it. So, as far as the pump was concerned,
the engine was always hot! Therefore,
no cold start. I have machined a shim.
No doubt many other adjustments are
also off, the timing was off by 50 degrees. Funny thing, she ran very
well......... BTW, the shim is 5mm thick.

[Kjell]

I also made up this simple dummy T/A.

[vangos]

Hi Kjell,
That's a nice looking shim. Did you machine it yourself or did you get it from somewhere? My rebuilt T/A also extends a little too much so I need to use a similar shim to get the gap adjusted perfectly.

Thanks,
Vangelis

[Roadtrip]

27mm T/As (extended length at 170 deg) were used until about 1976. Now only the T-260/1 and newer (29-31mm) model T/As are available now. On early SPICAs the flange to tip distance cold (68deg) should be 23mm (+/- 1mm). If it's not, then a shim can be added to make it so. A simple washer can be used. You might have to file two side in it to clear the mounting screws.

As far as the pump timing goes, it's not unusual that the engine to run ok with a badly timed pump, although here's some symptoms:

1. Sluggish performance
2. Flat spots
3. Poor fuel mileage
4. Need lots of throttle to maintain speed
5. Black tailpipe
6. Difficulty in setting mixture

When replacing the T/A, set the pump gap with a dummy actuator, NOT the T/A itself. Using a dummy is the only reliable way of setting the pump gap correctly. Although if you heat the engine (and maintain that during the procedure) to the point that the T/A is protruding exactly 27mm, you could use the T/A itself.

[Kjell]

Hi Vangelis, I just made it in my spare time at work.... A tool for adjusting the
mixture is next.