Honda GX670

[Art Dotson]

I'm new here and I'm looking for some guidance.

I have a Honda GX670 motor on a sawmill that is stored outside year round. It is usually covered with a tarp to keep the weather out, however last winter the tarp was blown partly off and while replacing it, it caught on the hose connecting the air filter to the carburetor. The hose got turned upward and funneled snow melt or rain down into the motor. BAD LUCK. I cleared the water from the crankcase and cylinders and added new oil and filter. The motor turned over and started seemingly without issues. It ran a little rough initially but smoothed out quickly and seemed to run fine. Next day I went to use it and it wouldn't turn over. Checking things I found that the crankcase and cylinders were full of gasoline. I'm thinking the float stuck open and it siphoned itself full over night. I cleared all of the gas and added new oil and filter and added a fuel shutoff valve inline for safety's sake. It started and ran OK, a bit rich it seemed. I was able to saw a couple of logs with only a few backfires. Next day I went to saw again and managed a couple of cuts with no problems till I got to a tough spot in the log and the governor opened and I got a lot of smoke out the exhaust. That cleared and I tried it again and again when the governor opened I got lots of smoke. I shut it down and noticed a lot of oil residue in the exhaust system. I'm about to tear into this to see what's amiss and would like some ideas on things to look for to indicate what may have happened. I'm guessing some of the water froze solid at some point and either cracked something or displaced a gasket or seal. What do you people think?

[okie]

Hello Art

One of the first things I would do is (before tear down) run a leak down test. If you don't have a guage with a pressure dial, you can get a pretty good test by ear.

Travis

[bobodu]

Yep....run the piston all the way up and hold the crank. Introduce so air in the sparkie hole and listen for it to come out. Might just be a head gasket.

[Greyfox]

Also you said it got water into it, do you know if the water made its way into the cab?