L have a toro rideon with onan engine l have replaced the starter motor and now l am getting oil up the breather pipe in to the carburetor and since this is happening l wish to know if this will hurt engine or not.
Or if l can get the problem fixed.
Cheers
Malcolm

Hi,
Sounds like unrelated items. You are getting air into the crankcase that forces oil up the breather on the piston downstroke. This pressurizes the crankcase causing oil to blow by the breather. You did fail to give any engine info, so that is about as complete an answer possible. Could be a bad breather.
Peace,
Clarke

Cheers for that Clarke.
L have drained oil and replaced oil and oil filter as l cheaked oil level and seen it was higher then it should have been.
The engine is onan b48g-ga020/4051c
If that helps you with your answer with my problem.
The mower now starts first time every time but still have oil in breather pipe not as much as l did before but still there.

Hi,
Sounds as if you had gas in the oil raising its level. It could have damage the flapper on the breather, or it could be clearing itself out. You should be able to get a parts breakdown at Toro with the model number off the machine at:
https://lookup3.toro.com/partdex/index.cfm?xCaller=Toro&lang=us_en
Peace,
Clarke