overfilled hydraulic fluid

[eric5324]

hey guys, my hydraulic fluid was a little low and i dumped some in. so i went to work and checked it a while later and it was coming out the dipstick. do you think this is bad?? i guess i'll have to drain some more out before i use it again. oh yeah it a ck20 hst. thanks, eric

 

[TedLaRue]

Did you check the level after you "dumped some in" ? And did you wait 15 or 20 seconds before checking the level. You apparently overfilled it, possibly because you were on a slope when you checked it, but also possibly because you didn't wait long enough for the fluid to drain down into the sump and level out.

I think you're wise in planning to drain some out before using it again. Engine oil can foam if the crank dips down into an over-filled crankcase and stirs it up. I don't think that would be a problem for your hydraulic oil, but having it leak out the dipstick hole is a problem that probably should be fixed.

 

[IslandTractor]

I managed to do that a couple of times with my CK20 before figuring out what the problem was. If you check the hydraulic fluid before you start the tractor sometimes the dipstick will read falsely low. Best to check it after you've started the machine and moved it a bit. Not sure exactly what the issue is but likely some sort of vacuum in the dipstick tube that needs to be equilabrated with atmosphere before reading.

You probably shouldn't leave extra fluid in as when it gets hot it can come bubbling or foaming out of the dipstick tube. Don't ask how I know.

Open the drain plug slightly until it flows out but the plug is still in place. Remove about as much as you put in then tighten the drain plug and check the level again. You can also use one of those dipstick tube pumps to suck extra fluid right out the dipstick tube if you don't like getting underneath the tractor.

 

[darkviper]

I managed to do that a couple of times with my CK20 before figuring out what the problem was. If you check the hydraulic fluid before you start the tractor sometimes the dipstick will read falsely low. Best to check it after you've started the machine and moved it a bit. Not sure exactly what the issue is but likely some sort of vacuum in the dipstick tube that needs to be equilabrated with atmosphere before reading.

You probably shouldn't leave extra fluid in as when it gets hot it can come bubbling or foaming out of the dipstick tube. Don't ask how I know.

Open the drain plug slightly until it flows out but the plug is still in place. Remove about as much as you put in then tighten the drain plug and check the level again. You can also use one of those dipstick tube pumps to suck extra fluid right out the dipstick tube if you don't like getting underneath the tractor.

I can duplicated the issue of not reading on the dipstick everytime i get on my CK20. You dont have to crank it. Simply take the dipstick out and wipe it off with your fingers. Then insert it and you will get the right reading. I talked to a few of the local farmers and they have seen this on thier machines sometimes to. Nobody has an answer as to why this happens but it does

 

[Ricktx]

I have noticed on my CK30 that the level of the hydraulic fluid on the dip stick is consistently low on the first pull of the dipstick. clean the dip stick and re-check. Everytime after that it is consistent. Possibly the dip stick tube is getting a slight pressure and keeping the fluid out yielding a false low level.

Just my 2 cents worth.

 

[malk315]

I've seen the same behavior on my CK-20.

To get the stick to read correctly before pulling it after the machine has been sitting for a while, you can loosen the red filler cap by the seat which will allow things to equalize. When the dipstick or filler cap are allowed air to pass, things read normally.

When my HST system used to pressurize due to a clogged vent, the red filler cap always needed to be loosened first or I would get the same behavior eric describes, but that was due to pressurization, not being overfilled. The red cap would release like opening a 2 liter bottle of soda.

It wouldn't hurt to make sure the vent isn't clogged. It's behind the gas tank (about mid tank I think tucked under a mount of some type) and it's about 1/4 - 3/8" diameter tube that's like an upside down letter "J" like a gas vent for an underground gas line. There's no way to look up in there w/o removing the tank and unscrewing the vent, but you could perhaps use a piece of wire to just make sure it's clear.

Mine was clogged by a mud wasp that sealed it off. I have a post if you search for posts by me that describes the whole event... geyser of HST oil out of the dipstick and all over the dash, foot deck area, and mower deck...

Best of luck.

-Eric