Hydraulic pressure blows out dipstick tube

[Smokeydog]

Small cracks on a rubber elbow on the suction side of the hydraulic pump allowed air in but very little oil out on my Kubota B26. Enough air to foam up and expel hydraulic oil out vent when hot. Design flaw that Kubota eventually redesigned suction line from filter to pump. Check all suction lines and filter.

 

[rScotty]

The mud dapper wasps are terrible for plugging vents.

That's a common reason & what I'd look for too. The vent is often a short tube on the highest point of the rear casting - often under or behind the back of the seat. Irresistable to those mud dauber wasps. Clean out the mud & put a screen over the end.

 

[LouNY]

I have used the inexpensive clear in line fuel filters at times.