'71 Snag without power

[Stephen Woolverton <stephen@domain.elided>]

Hi All:

I have a '71 US Stag. It was running just fine (at about 80mph) when a 
clack came from under the hood.* Later I discovered the mounting screw 
for the condenser in the distrubitor had come out and bounced around 
inside the distributor.* I replaced the mechanical ignition with a 
Lumenition Ignition kit (but not the coil) and the Stag started right 
back up. *

But here's the catch... 
Under a cold-choked condition the engine has _some_ power. 
But when the engine warms up it has no power...just enough to free idle; 
put it in gear and it pops and stalls out.

I'm guessing the fuel mix is too lean. 
(ie.: engine runs near poorly when cold and choked, pops, caughs and 
stalls when warmed.)

I have checked: 
a) the timing is set to four degrees before TDC (set at idle when 
cold-choked); **
b) vacuum advance moves the plate with 15 inches of vacuum;
c) the diaphrams at the top of the carbs are in good shape (a pair of  
Z.S. 175 CD-2);
d) as far as I can tell the timing chains are on the correct cogs...
     each cylinder has compression;
e) fuel supply is up (as checked at the out end of the engine compartment 
filter)
f) the CV (crankcase ventlation) hoses will be replace this evening with 
tightly fitting ones
g) [the big clue] the vacuum actuated valves in the SU's never seem to 
lift 
     more than 3/8" even when throttled up (with no load) to 4,000 rpm.

Does anyone have any suggestions? 
What should I check/adjust next?

I am nearing the point of taking the car to one of those professional 
mechanics 
and that would take all the fun out life.

Thanks for your suggestions


* To make a long story short I won't share the part about blocking a two 
lane thoughoufare for three hours on Sunday morning when all the church 
goers were migrating or the part about the flames that shot out 
alternating between the carbs and the broken exhaust pipes or how my 
eardrums got blown out when one of the spark plugs blew out of the head 
or the part about the tow truck driver who let my MG Midget crash into 
the side of my garage or the part about the other tow truck that later 
collected the Midget or the kids that slashed a new tire on the Beetle or 
what happened when I hit the gas instead of the brake pedal and ran the 
Stag into the 6X6 support in the basement (and I thought only those 
people with the "Unexplained Acceleration" in their Audi 5000's were 
incompetent drivers.)

** The distributor's adjustment (two bolts at the block) is max'd out in 
one direction. I had thought for a while that maybe the distributor 
jumped a tooth down in the engine; this I have not looked into.)





Stephen
- - - - - - -
Stephen Woolverton
Marathon Computer, Inc.
80 Fesslers Parkway
Nashville, TN 37210
615/242-9700
615/255-8040 fax
www.marathoncomputer.com