73 Spider - SPICA

~Zaitsev wrote:
>
> In the cold (rich) position is the plunger up? One would expect that
> if it operates on heat, then, upon heating, the fluid would expand and
> depress the switch and turn the fuel enrichment plunger down (off).

'Cold', the plunger aught be "up" ... fully retracted , rich
'Hot' , the plunger aught be "down" ... fully extended , lean

I'd opine that the heat-expanded fluid 'volume' ,
with engine running at rad_thermo 'temp',
is enuf to fully 'extend' this plunger/piston ,
which then depresses the Spica internal 'lever
to it's factory "set", full lean position ...
full F/A mix lean position.

Internally,
the "lever' acts upon a rack/pinion gear system ,
which controls the crank "throw' of the Spica's internal fuel-pumping
pistons ...
.. more 'throw' = rich
.. min 'throw' = lean , hot running F/A mix

Envison a outer crank bearing, ...
and within 'it' ,
yet another 'inner' bearing.

The inner bbg is mounted to/on 'a' crank journal ... 1 of '4' ...
The outter bbg is "captured" by the piston rod 'halves'.

If the inner crank bbg is mounted off-center ,
within the 'confines' of the outter bbg ,
&
the outer bbg is mounted 'centered',

Any rotation of the "inner" bbg will increase/decrease
the actual 'throw' of the entire [piston/rod/bbg] assembly ,
depending upon the degree of rotation of the inner bbg.

The 'TA',
acting upon the 'lever' ,
acting upon a rack/pinon gear assembly,
which rotates this inner , crank bbg ,
increasing/decreasing the 'throw' of the fuel-pumping piston ,
thus,
incresing/decreasing the amount of fuel injected, per intake cycle.

'Simple' , 'qed', when seen disassembled ...
but "dont".

Essentially,
the inner bbg allows the center of the crank journal
to rotate =within= the confines of the rod 'halves', and it's outter
bbg,
and further, within a prescribed circle .

This 'rotation' controled by the rack/pinion arrangement .
inturn ,
controlled by the 'lever'
inturn ,
controlled by the 'TA' piston.

The TA fluid-expansion 'piston'
moves this internal 'lever' up/down
moves this rack/pinion as required ...
hot to cold, & the reverse.

I cant quite recall whether the rack is 'fixed',
or the pinions are 'fixed',
and the "other" moving , controlling the effective crank 'throw'.



> Or, is just the opposite?
> Or....does my physics suck?

Nope.
Nope. ( ... and, spatial aquity )

Ed

That's why I published some links down this thread.
Just bother to follow them and you already had your answer.
http://www.alfamontreal.info/Montreal/TAextension.jpg

--
Ciao from Holland
AlfistaGJ (Gert-Jan)
Now:
Rosso Radicofani GT 2.0JTS (2005)
Golden Montreal 1428700 (1973/4)
And former owner of:
156SW / 2 155's / 75 / Giulietta / 2 33's /
3 Sud's / Alfetta GT / Montreal / 2000GTV /
1300GTJ / 2 Giulia Super's

"~Zaitsev" > schreef in bericht
...
> In the cold (rich) position is the plunger up? One would expect that
> if it operates on heat, then, upon heating, the fluid would expand and
> depress the switch and turn the fuel enrichment plunger down (off).
>
> Or, is just the opposite?
>
> Or....does my physics suck?

Using the TA:

Am I to understand that the screw/bolt is adjusted for a 'cold' start
then readjusted manually once it warms up?

~Zaitsev wrote:

>
> Using the TA:
>
> Am I to understand that the screw/bolt is adjusted for a 'cold' start
> then readjusted manually once it warms up?

No, the original unit will make the adjustment automatically, in the manner
of the old automatic chokes, or more modern cold start enrichment systems.
--
Catman MIB#14 SKoGA#6 TEAR#4 BOTAFOF#38 Apostle#21 COSOC#3
Tyger, Tyger Burning Bright (Remove rust to reply)
Alfa 116 Giulietta 3.0l (Really) Sprint 1.7 75 TS 156 TS S2
Triumph Speed Triple: Black with extra black bits
www.cuore-sportivo.co.uk

Wait, now. What I have existing (I got the courage to take it off) is
a hollow brass sleeve with the mounting assembly on it and a brass
screw extending down into the FI pump. It appears like the end of the
sleeve at the very tip was threaded at one time but has stripped. But
in its original position measured 27mm which checks out with the book.

Catman, when you say the 'original unit', do you mean the cold start
solenoid, the FI pump itself or the TA?

Thanks

W Roberts

On Sun, 05 Jun 2005 21:05:37 +0000, Catman
> wrote:

>~Zaitsev wrote:
>
>>
>> Using the TA:
>>
>> Am I to understand that the screw/bolt is adjusted for a 'cold' start
>> then readjusted manually once it warms up?
>
>No, the original unit will make the adjustment automatically, in the manner
>of the old automatic chokes, or more modern cold start enrichment systems.

~Zaitsev wrote:

> Wait, now. What I have existing (I got the courage to take it off) is
> a hollow brass sleeve with the mounting assembly on it and a brass
> screw extending down into the FI pump. It appears like the end of the
> sleeve at the very tip was threaded at one time but has stripped. But
> in its original position measured 27mm which checks out with the book.
>
> Catman, when you say the 'original unit', do you mean the cold start
> solenoid, the FI pump itself or the TA?

The TA.

--
Catman MIB#14 SKoGA#6 TEAR#4 BOTAFOF#38 Apostle#21 COSOC#3
Tyger, Tyger Burning Bright (Remove rust to reply)
Alfa 116 Giulietta 3.0l (Really) Sprint 1.7 75 TS 156 TS S2
Triumph Speed Triple: Black with extra black bits
www.cuore-sportivo.co.uk

"~Zaitsev" > schreef in bericht
...
>
> Using the TA:
>
> Am I to understand that the screw/bolt is adjusted for a 'cold' start
> then readjusted manually once it warms up?

That's one way to us it, just screw it in as far as the original TA would
extend at 80-85dgr C (see graph at
http://www.alfamontreal.info/Montreal/TAextension.jpg)

How does it do that? By disengaging the cold-start solenoid?

On Mon, 06 Jun 2005 05:55:00 +0000, Catman
> wrote:

>The TA.

At 80 deg C the chart shows 29mm for Montreal and early 1969. 27mm
for late 1969 thru 1974. I have no idea if this is a Montreal or a
'regular' Alfa. It's just a Spider as far as I know. Anyone know how
to tell the difference?

Thanks, yet again.

W Roberts
San Antonio, TX

On Mon, 6 Jun 2005 09:00:43 +0200, "alfistagj"
> wrote:

>That's one way to us it, just screw it in as far as the original TA would
>extend at 80-85dgr C (see graph at
>http://www.alfamontreal.info/Montreal/TAextension.jpg)
>

I'm having a machinist fabricate a dummy TA ($40 bucks). If it
doesn't work, I'll spring for a remanufactured one. But when I
remount it, should I add change any lube oil in this section or just
reinsert it and bolt it down?

Tnx,

WR