At 04:00 PM 7/19/2000 -0500, George Cahlik wrote:
>.... '74 MG Midget, ....
>....
>.... After about 45 minutes of abuse, and a stall, I tried to start up the
car, and it startd to run rough and backfired. .... couldn't achieve the
power to go above 40 mph.
>
>.... took a few pictures .... What I think happened .... is that the hose
from the fuel filter came loose or broke ....
>
>.... webpage with my images ....
>http://home.earthlink.net/~styloroc2000/midget.html
>....
The canister is not a fuel filter, but a fuel vapor absorbtion device
filled with carbon granuales. It is conected to the vent/overflow
connector on the carburetor(s), and also to a vent tube for the fuel tank,
and to the engine air intake. It is intended to absorb fuel vapors from
the carbs and fuel tank when the car is not running, and to later release
these vapors into the engine to be burned when it is running. Having
liquid fuel running out of the absorbtion canister indicates that the fuel
level float valve in the caburetor is stuck in the open position, allowing
fuel to run continuously into the float chamber and to overflow through the
vent tube into the vapor absorbtion canister.
On your carburetors the float chamber is on the side of the carb with hoses
attached to the cover of the chamber. If you disconnect the vent hose from
the cover(s) you should see fuel running out of the offending unit when the
engine is running. Remove the cover from this float chamber and inspect
the float valve. It works like the shut off valve in a toilet tank, with
the rising float pushing the fuel inlet valve to the closed position.
Leakage here can be caused by a punctured float that does not float because
it is filled with fuel, or by some dirt in the falve, or by the valve
becoming dislodged from its seat.
Now from an old codger who is not fully up to speed on either Midgets or
emissions controls, it appears to me from the picture that your carbon
canister is a part from a later model Midget, 1977-1979 (not that it makes
any difference). That lower tube fitting would be connected to an anti-run
on valve. The functional idea is that when you turn the engine off the
anti-run on valve applies a vacuum to the vapor venting system, which in
turn causes a vacuum in the carb float chambers, whin in turn prevents fuel
from entering the main jet in the carburetor, so the engine stops
gracefully for lack of fuel.
Sometimes wishing I could afford a newer car,
Barney Gaylord
1958 MGA with an attitude
http://www.ntsource.com/~barneymg
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