Good day;

I've got a 1986 MTD lawn tractor with a B&S 18 HP twin cylinder engine (sorry, I can't make out the model number -- the engine cowling was painted over).

The left cylinder seems to be fairly dead. Here's the symptoms:

- Runs rough with reduced power

- Pulled the plug wire from the left cylinder with minimal change in RPM.

- Pulled the plug wire on the right cylinder and engine dies or barely runs unless full choke is applied.

Here's what I've done to date (after reading several similar questions here and elsewhere):

- New plugs (some improvement, the old ones were pretty bad)

- Compression on both cylinders ~100 - 110 PSI

- Connected plug wire from "dead" cylinder to "good" one (other one won't reach); engine runs as before with "bad" cylinder plug wire disconnected

- Squirted a bit of gas directly into "bad" cylinder, replaced plug, disconnected "good" cylinder and started. It back-fired (of course), then kicked over ran (poorly), then nearly died until fully choked.

- Dead cylinder plug does not appear to be wet or fouled from running.

I'm new to small engine repair, so please forgive me if I've missed something.

Summary:

Compression is good.

Spark seems good (confirmed by switching wires).

Plugs are new.

Bad cylinder's plug isn't wet after short runs (though it is hot).

Bad cylinder alone runs (poorly) with full choke.

Seems like a fuel problem; does the carb have separate feeds for each cylinder?

Any suggestions?

Many thanks for your help (including the earlier postings).

Cheers!