Hydraulic oil leaks from cap, normal?

[dirtyb115]

Hi all. Noticed i had quite a bit of hyraulic oil on the side of my 763 while i was working on an incline over the weekend. It all seems to be coming from the cap, is this normal, or do i need a new one?

 

[thetool]

The cap is vented. If it has a filter in it (new, like a white sponge) that gets oil-soaked, you might want to replace it. There is also a gasket between the cap and tank.
It shouldn't leak unless it's overfull or foaming up, but I guess it depends on your work angles.

 

[tsak]

Thought I had the same problem on my 873. Turned out to be a pin hole leak in the oil cooler. Look inside the fan vent above the oil fill cap with a flashlight, if the fan is covered in oil it may be the cooler. Also look at the site glass on the oil tank, my oil started to look dirty real fast. Every time you shut down the pin hole sucks air and dirt into the cooler as it drains oil back to the tank. Has anyone ever tried to repair a leaking oil cooler? The new one was $300

 

[Tazza]

Thought I had the same problem on my 873. Turned out to be a pin hole leak in the oil cooler. Look inside the fan vent above the oil fill cap with a flashlight, if the fan is covered in oil it may be the cooler. Also look at the site glass on the oil tank, my oil started to look dirty real fast. Every time you shut down the pin hole sucks air and dirt into the cooler as it drains oil back to the tank. Has anyone ever tried to repair a leaking oil cooler? The new one was $300

If you can find the leak i see no reason why you can't silver solder the crack/hole up. Even if you need to remove a few cooling fins to do it. You really have nothing to loose, if it fails you have to buy a new one, if you succeed you spend a little time and a few dollars of silver solder.