Snake Under the Hood

[robertm]

I have a B7500 with only about 35 hours on it. Recently, in colder weather start-ups, I notice a hissing noise when I first start-up the tractor. After it warms up, it goes away. It sounds like its a blow-off somewhere around the engine, but I can't define it. I am used to a waste gate opening on my Powerstroke when it's cold, but is there such a thing on a little Kubota? Hiss Hiss Hiss. /w3tcompact/icons/laugh.gif

 

[Woodbeef]

Could just be an exhaust leak caused by metal contraction during colder weather. Once it warms up and expands it goes away.

 

[snowman]

My B7500 does the same - has never caused a problem that I'm aware of - a little over 200 hours now

 

[JimMc]

I had a four wheeler once my grandfather rode from hi house to ours every morning and back to his place each evening (about 100 yards). When I rode the four wheeler for a longer period it would hiss and finally got to the point where the hissing got louder and would kill the engine. Turns out the short trips would create condensation which settled in the muffler. As the engine warmed up it boiled the water and expelled the steam. Once we ran it long enough to evaporate all the water it stopped. We began to let it run each weekend for a couple hours to keep the moisture from accumulating and it never happened again. Mechanic told us that's why most four wheeler exhausts rust out. They don't get run long enough in winter. If you only make short runs in winter could be your situation too.