I've now had two 17.5HP vertical shaft riding mower B&S engines lose their oil from a crack in the bottom of the crankcase. My theory is that the engines need to be mounted on rubber mounts, because today's flimsy chassis frames will flex when you have one wheel of the mower raised from approaching uneven terrain. Then the engine gets stressed from the twisting of the chassis?
#2
sgkent
crack or bottom gasket? Lots of folks here have had issues with the crankcase gasket failing.
Leaks with V twins, OP needs to post engine model numbers when asking an engine questions as there are at least two 17.5 hp B&S vertical shaft engines completely different, maybe 3 come to think of it.
Walt Conner
Being belt driven flex as you describe is not a problem that would cause the oil to drain from the crank case.
Broken gaskets , failed oil seals , loose dip stick tubes , blown head gaskets , holes in crank cases , worn out piston rings will all cause the oil level to drop .
One of the big downsides of ash less synthetic oil is most do not burn & those that do not burn do not smoke as it blows out the muffler.
So where does the oil accumulate on your mower ?
A bad gasket will cause it to pool on the engine bay floor .
A bad bottom seal will run down the shaft, pool on the pulley then get flung over the side rails
A bad top seal will blow all over the sides of the engine because of the effect of the cooling fan.
And as Walt has already asked, we need the engine numbers, mower make , model & serial number .
We also need to know what you are doing with your mower.
consuming the oil in the sump is a very rare occurence, to have it happen twice makes we wonder if it is operator related.
Very hilly properties must be mown with a horozontal shaft shaft or two stroke engine
