Power Washed H Now Runs Rough

I am brand new to tractors. I have a few friends that antique pull and thought I would try my hand. I bought my first one last week, a 1941 Farmall H. Anyhow the motor ran like a swiss watch and started after half a turn before. Well I power washed it and now it runs quite rough and blows black smoke. I checked the distributer cap and it didn't seem to have any water in it but I dried it out and took the coil cover off to dry for most of the day. I also checked all the plug wires and I didn,t knock any loose. It seems to idle fine but when I run it up it runs rough and smokes like a chimney. I am a pretty good auto mechanic but his is my first foray into diagnosing a tractor. Could it be a governor problem? Any help is greatly aprreciated

Oh also is has the original Magneto and was NOT converted to 12v. The mag was rebuilt just a couple months ago.

I have not been around H's and M's too much but sound like you may have hit the lean/rich adjustment on the carb with your power sprayer. The old Case I used to have did not have any friction left on the adjustment screw (carb was old and needed rebuilt). I used to put a wire tie around it so it would not vibrate out of adjustment. The symptom you describe is too rich of a fuel mixture, turn the adjusting screw (about 1/2 turn at a time) in with the engine at 3/4 to full throttle and see if it mellows out.

Did you get the air cleaner full of water?

You may have gotten the plug wires wet and on the
mag's cap too. Some may have gotten inside the mag. Take one plug wire off one at a time and dry them then reinstall it so you don't get the wires crossed. Remove the cap and see if any water entered it. Hal

If you allready checked the mag and you say it is indeed dry I would then have to agree with the gentleman below. It's likely a restricted airflow from carb to air cleaner (water in air cleaner). Easiest check would be to pull the hose off the carb that runs to the air cleaner and then fire the engine. If the symptom disapears the problem is in the air cleaner. If not it's possible that water got past the air cleaner hose into the carb intake, I have had that happen before as well. As for the governor, unless a part inside failed at the same time you powerwashed it I would say no. The governoring mechanism is all internal all the way to the carb so powerwashing should not have affected it.

I used to always have problems like this when I powerwashed my tractors. I now use a garden hose hooked to a hot water faucet, a good hot bucket of soapy water and a wash rag for the tinwork and a good commercial degreaser and a heavy scrub brush for the frame and places where the grease is. My problems have all but disapeared keeping the powerwasaher away from the tractors. Just some food for thought.

It's shaping up like water, on either the fuel or the ignition side. If you blew enough water in under an old gasket on your fuel tank cap, you could be drawing water down to the carb from there. If you got enough in through the air cleaner, you could have overfilled the oil cup at the bottom and be drawing water in from there.

On the distributor cap, wiping it down and anything inside, then spraying with WD-40 (the WD refers to its water-drying abilities) and wiping that down and letting it air dry a few minutes might just do the trick. do the same with the sockets on the coil and distributor caps for the wires in an out of them, pating attention to the location of your plug wires. I'd be really surprised if you got any water in by the coil cover or the internal cover between the dist cap and the internal cavity where the condenser and points are, but couldn't rule it out. Is it possible that you saturated the insulation on the wire that grounds your magneto enough that it's giving you a weak, intermittent ground making it run rough? -- that would be most likely near where the insulation frays near either the ground stud on the mag or near the switch.

Taday it seems to run much better. I consulted a local and he said I probably got water in the intake like a few have suggested. I took it down the road today and wound it out; no more smoke or missing. I am just glad that it wasn"t something too bad. The power washing did let me know where all the leaks are now LOL. Have to change the water jacket plate gasket, and a couple other little things. Thanx to all for the help.