The main leaks on a K-jet system are at the idle speed control valve,
the boot on the throttle body, and the hose at the cold start valve.
Note that a cold start valve failed open will flood the engine badly
at idle.
Here's what I would do:
Remove the air filter housing and verify that the air meter flap is
all the way up with the engine off. If it's not, you will have to
remove the fuel distributor and find out why. Even slightly depressed
below zero position will cause the engine to flood at idle. If it's
rubbing on the venturi it will also run lean immediately on throttle
opening until it unsticks.
If it's all the way up, press down gently (engine off, but fuel
pressure). It MUST move smoothly with no hangs or roughness and MUST
return fully to the zero position all by itself. If not, the pivot or
pressure pin is binding. If you see any problems, remove the fuel
distributor, take the boot off, and pull and clean the pivot pin.
Should restore normal function (this is a problem with cars that have
had a bad air filter or a big vacuum leak). You may need to pull the
regulator pin on the bottom of the fuel distributor and clean it,
possibly replace the seal if there is fuel leaking.
Check to make sure you didn't use a long screw when putting the boot
back on the fuel distributor in the one spot you have to use a short
one, as this will crush the position sensor and cause all sorts of
problem with the computer. Also verify that the computer connections
are clean and properly installed.
Verify that the idle control valve hoses are not cracked or loose on
the barbs of the idle control valve. Chronic issue with them, they
split down the mold line for me and I've replaced them three times on
the TE so far. I ended up using hose clamps, solved all sorts of idle
problems. Might flush the idle control valve out with carb cleaner,
they are usually dirty.
Verify that the boot from the air flow meter to throttle body is
actually over the back side of the throttle body, it's a HUGE pain to
get it right. Always install the back side first, then pull it over
the lip on the fender side where you can see what you are doing. If
it's not over the lip all the way around, you are going to have fits.
Check for fuel in the vent line from the regulator to the crankcase
ventilation hose. If there is any fuel in there, the regulator has
failed and can be over-pressuring the system, which will flood.
It is very unlikely that the fuel mixture needs to be changed --
almost always, you have another issue causing the problem.
Test the cold start valve. You can pull it out of the hose while
still attached just after shutting the engine off, if its' dripping,
replace it. If you have a helper, have them start the car with the
valve out of the hose but still connected, it should puff a very short
squirt unless it's very cold, then stop completely. Dribbles will
flood you out.
If nothing seems wrong and it still runs rich, I would clean the pivot
and regulator pin on the old fuel distributor, fix the vacuum leaks
(likely a hardened boot and idle control valve hoses) and re-install
it. Sadly, sitting unused causes serious problems with K-jet fuel
distributors, and in the worst case the diaphragm corrodes through.
This results in fuel pouring into the engine, just as you describe. A
stuck meter flap will do the same thing, though, and is easier to fix.
Peter
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