Troubles starting

[Vancouver '66]

Diagnosis please!

Car was recently tuned and running great. Ran for about 8 outings not a problem. Left it for a week, then couldn't start it to save my life.
Engine turned over and almost started, but just wouldn't catch.

After hooking up to another vehicle for a boost, repeated tries eventually got it to start...with huge backfires at low rpms and idles (cleared up over 2000 rpms).

Since then, it starts after about 20 or 30 tries, then runs awful at low rpms... again, backfires and popping. After it warms up, the backfires stop, but idle is still rough.

Ideas? I have no clue what to do.

Michael

[WFBowen]

Michael:
First check for any vacuum leaks - especially vacuum take-offs or plugs at the carb bases. Check your ignition - sometimes a faulty plug or wiring can result in a cylinder(s) loading up with gas (& the exhaust port) then when it does fire you get a major backfire & make sure your ign. points have sufficient gap. If you pull the spark plugs when it "almost starts" you can sometimes tell which plug isn't firing and at least isolate the problem cylinder.
If this doesn't help, re-check valve adjustment, timing, etc. At this point, you'll probably want to check the carbs for a stuck float valve or maybe clogged jet.
Do you ever smell gas when it won't start?
Bill.