Have a problem with hydraulic drive on one side fading out after mower gets hot. Reservoir is full, no leaks and hex lug on pump is tight. This only happens after operating for about 2 lawns when it's hot. If it cools down it functions ok again until hot. The mower is under warranty but my dealer is closed until after the new year. Just wondering if anyone has experienced this or have an opinion what it could be. Thanks for any input.