Chris,
How many miles on that engine and what's the compression readings? My 68
2000 kept failing emission inspections and I would have to tune the carbs
real lean to get it to idle correctly, otherwise it would just sort of flood
out (bog down). It wasn't until I replaced the stock air cleaner assembly
with a couple TR6 chrome round ones and rerouted the valve cover hose into a
custom configuration did I discover the cause of all my problems : BLOWBY
from a few weak rings was being injected into the idle mixture making it
extremely rich, thereby making for a rough idle and failed inspections. I
suspect you have a bad ring or valve stems that are letting compression past
and it gets worse when you race the engine, which is why even a 2,000 rpm
idle still doesn't prevent it from stalling.
There's no real way to fix it without an engine rebuild except to run the
hose down the side of the engine and vent into the atmosphere like old Chevy
trucks used to through a " breather pipe", so it was called.
Mine was nowhere near as bad as yours in that I only had to raise the idle
to 1,200 rpm to keep it running.
You can check the amount of blowby by holding your finger over the tube from
the valve cover and see how much and how fast pressure builds up. You will
probably be able to see some slight smoke coming out. If this is the case I
bought an inexpensive filter for a Chevy at the parts store that has a felt
filter and design to hold oil accumulation...fits in the hose and works
somewhat until you can tear the engine down.
My 2 cents worth.....
Marshall
> ..My '69 1600 boggs and will stall when the breather from the valve cover is
> attached to the airfilter housing. the tube is not clogged, and the engine
> runs absolutely fine without it attached. if i raise the idle to maybe 2000
> rpms, it runs fine unless i quickly rev it and then it will stall. any
> ideas?
>
> thanks so much,
> Chris Gray
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