Dean:
Engine won't hold an idle, even when fully warmed. I can
only keep it running by blipping the throttle or pulling
out the enrichment knob. Otherwise, it just slowly dies.
"Enrichment knob"--is that a choke knob? If the idle returns to normal when
you pull it out, I would suspect either a vacuum leak or dirt in a carb.
But first, at idle, throw your timing light on each spark plug lead and make
sure you see solid, even flashes on each plug. If you see anything but,
look into your ignition system. If you see nothing suspicious there, look
for vacuum leaks. They almost always hide in rubber hoses, so check your
brake booster hose and its attachment points, the vacuum advance lines, and
any other rubber hoses on the intake side of the engine. I'm betting you'll
find something after a bit of examination. Keep in mind that you can often
hear a vacuum leak, so use your ears. Sometimes, using a piece of plastic
tubing as a stethoscope works well. Put one end in your ear and move the
other down the length of the hoses. If you can't find anything in the
hoses, then begin looking at the mating surfaces on the intake side: where
the carbs mount, where the intake runners attach to the head, etc. A good
way to find leaks at mating surfaces is to use an unlit propane torch. Put
the end of the torch near a suspected leak and slowly open the valve. If
there is a leak, the engine will suddenly run better. If not, close the
valve, let the gas dissipate for a few seconds and try another spot. No,
this test isn't OSHA approved.
If, after a thorough examination, you don't find any leaks, then I would
suspect that one of your carbs has a clogged jet orifice. It happens.
Fixing that would probably require tearing down and cleaning or rebuilding
the carb.
Rich Wagner
Montrose, CO, USA
'82 GTV6
--
to be removed from alfa, see http://www.digest.net/bin/digest-subs.cgi
or email "unsubscribe alfa" to [email protected]
