I have a strange problem - I have a 19.5hp opposed twin I/C on a Craftsman LT1000 that used to run great. I had busted up the hood, and took it off, and then when mowing up against a bush, I cracked the flange that holds the carburetor on the fuel manifold. I had a spare 18hp opposed twin that I bought to fix up, so I stool the manifold off of that. The cracked manifold was silvery cast metal, but the 18hp had a shiny black painted manifold. The manifold fit fine, and the engine started up fine. After about 30 minutes of cutting, it stalled out, and when I looked, the manifold was covered in condensation was quite cool to the touch - I wondered the fuel was evaporating in the manifold, and I was getting some kind of vapor lock keep fuel mist from getting the engine. I tried insulating the manifold with aluminum foil, and that didn't seem to help much. Then I tried insulating the two exhaust pipes and muffler. and I am still getting stalling after 30 minutes of cutting, and the manifold is always dripping with condensation. I don't ever remember that happening before I changed the manifolds. Any thoughts on what's causing either the condensation or the engine to die out after a short cutting time. It restarts easily, and usually will run for 10 or 15 minutes before dying out again.
Your engine is running cool all the time since you removed the hood, with hood on engine will reach normal operating temperature faster & more efficient.
#3
StarTech
Ever of heard carburetor icing? It can occur as warm 70F+ especially with ethanol fuel blends. I even had 100LL fuel to ice over a carburetor at 80F when flying.
Ever of heard carburetor icing? It can occur as warm 70F+ especially with ethanol fuel blends. I even had 100LL fuel to ice over a carburetor at 80F when flying.
Just for the record, the condensation issue was not the sign of vapor lock or anything weird like that. I found some small grass clipping debris in the bottom of the gas-tank. The mower would run for 20 minutes, then the debris sucked up against the exit hole in the tank, and tractor died out. It would start almost immediately, but would die out in shorter and shorter time intervals. Once I drained and cleaned the tank, the problem went away.
