List,
A "hard starting" question to ponder please....not a big deal - more of a
nuisance now that the weather is colder and I don't run the Spit as often as
in summer.
After a week of no use, the Spit needs to crank 3 or 4 times before firing
up....when it does, the exhaust note is normal (no billows of black smoke
from an overly rich choke mixture). I didn't experience this in summer even
after a rare one week without use. Ignition, plugs, etc, all OK - engine
runs fine after short warm up. Restarts after the engine has been running
are always very quick - like one or two crank revolutions!
Is it possible that fuel is somehow purging into the intake manifold from the
carb bowls (twin SUs) after an extended period of shutdown during colder
weather? Honestly, it sounds (no coughing, no spitting - just cranking) like
there's no fuel reaching the cylinders until after 3+ medium crankings.
Could a weak fuel pump diaphragm "stiffin up" in the cold causing weak pump
pressure. Perhaps the fuel level in the bowls is slightly lower than it
should be. Given that there's probably always some fuel evaporation from the
bowls, the cold-affected pump can't fill the bowls quickly enough to get a
"fast start"???
I'm really reaching for causes - it's probably something more obvious!
TIA,
Chip Krout
'76 TR6 CF57822U (Being Reborn For Y2K)
'70 Spit Mk3 FDU78512L
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