[alfa] Spica timing & tools

[alfacybersite <acs@xxxxxxxxxxxxxxxxx>]

Possibly I should have made the subject: Spica Diesel unit timing. Might
have received a few more replies.

Sorry, another Biba smart-ass comment.

Actually the three I received were very helpful. I especially like Jon
Pike's since it means I'm through except for slipping the belt on.

Since I've misplaced Wes's manual I opened an official Alfa manual for
the Spica unit (Maintenance Manual for AR 2000 Spider Veloce Fuel
Injection Models / 49 States Version 1977 Model Year - Public # 2546 -
6/77).

It states: "...follow this procedure to time the injection pump and
reinstall the drive belt:

"Turn the crankshaft over so as to bring #1 piston to the T.D.C.; remove
the spark plug from cylinder #1 to check that both valves, intake and
exhaust, are in the open position (overlap stage). (If the valves are
closed, turn the crankshaft over by one more revolution).

"In this condition, the mark "P" on the crankshaft pulley will line up
with the pointer.

"Rotate the crankshaft counterclockwise by 70 degrees, i.e. in such a
way that "I" on crankshaft pulley and pointer line up."

Then it goes on to say to line up pump pulley marks and install belt -
rotate either way a half tooth as necessary.

Being a visual person I kept trying to get the valves to look like the
drawing - meaning both were wide open. Finally the little 'duh' light
came on, I set my beer down, realizing the overlap is considerably more
visually subtle than that.

Unnh, I think I now know why it's okay to have the distributor pointing
to #4. Turned the page in same book and there is a neat drawing which
I'd never paid attention to. Might help some other's who are more than a
bit confused as to what is happening when on their Spica.

The drawing is done in a decreasing spiral: Freudian looking drawing of
the injector squirts at "I" / 70 degrees before T.D.C. Valve overlap
begins at 21 degrees 54 minutes before T.D.C. Exhaust valve stays open
for 15 degrees 14 minutes after T.D.C. then there is the induction
stroke ending all the way around at 69 degrees 54 minutes after B.D.C.
Then the compression stroke and the plug fires before T.D.C. (doesn't
give degrees and believe this varies as I'm sure the '75 / '76 CA Spica
fires after T.D.C.). then it goes on regarding the power stroke ending
at 15 degrees 14 minutes after T.D.C.

Yup another nail biter.

I'm going to check this out a bit further with the other two posts I
received on the subject - just to verify.

Thanks all.

Oh yeah, I believe I read or someone told me (heard Wes speak many years
ago at an AROSC meeting) that you can be 180 degrees off on the Spica
timing and it will run, just not as well. Don't understand how that is
possible, but wanted to avoid that situation - especially since I always
install Spica belt covers.

********

Someone recently posted they had received a number of Alfa specific
tools and wanted to know what other tools Alfa made / advised to use. In
the back of the above book there are very nice drawings of 24 tools for
the Spica. Interestingly I've seen (and wanted) a particular Spica
alignment tool which wasn't shown.

Biba
Irwindale, CA USA
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