There is a lot of oil leakage from both pumps on the top side. I have purchased new hose, and also the o-rings for the 4 fittings where the lo-pressure hoses attach. Looking at the parts diagram I also see an o-ring at the top (HG 9004101-1340) and another larger one where top head attaches to the lower housing (HG51232). Is it possible to replace those 2 o-rings without removing the pumps from the mower? If it is possible to remove the top head to get at that housing o-ring with the pump still on the mower it may be worth the trouble.