Bobcat 440 hydraulic fliud type?

Help Support SkidSteer Forum:

Eric lyle

New member
Joined
Feb 5, 2023
Messages
4
Hello, hoping for some guidance here. I have a bobcat 440 and I want to change out the hydraulic fluid do to the fact that it has foamed up and started overflowing. Im hoping this was do to running low on fluid. I added fluid but it has still foamed up and overflowed several times.I figured changing fluid and filter is the easiest thing to check first. I've been using Oreilys premium universal tractor fluid. Any help is greatly appreciated. My questions are:
1, am I correct in thinking that after that much air has entered the system it needs to be replaced because you can't get the air out?
2, is this brand of fluid ok to use?
3, is there a better option other than bobcat fluid?
3, how does one drain all the old fluid out. My maintenance book says drain the Reservoir but I don't see how to get the rest of it out.
 

brdgbldr

Well-known member
Joined
Jun 1, 2012
Messages
1,165
I won't get into what type of fluids to use because it always get out of hand on here and there are several posts on here you can refer to.

Bobcat machines self bleed air out of the system. Run the machine, let the foam settle, fill reservoir, repeat.

Foam can happen for many reasons. One is that some fluids do not have an anti foaming agent in them. Another is water in the system and another is that you have a leak somewhere and could be sucking air into the system.

The only way to drain all of the fluids out of the system is to remove the hoses and then disconnect the cylinders and cycle them. Another option is to change what you can and run all functions on the machine for some time and then change the fluid again.
 
OP
OP
E

Eric lyle

New member
Joined
Feb 5, 2023
Messages
4
I won't get into what type of fluids to use because it always get out of hand on here and there are several posts on here you can refer to.

Bobcat machines self bleed air out of the system. Run the machine, let the foam settle, fill reservoir, repeat.

Foam can happen for many reasons. One is that some fluids do not have an anti foaming agent in them. Another is water in the system and another is that you have a leak somewhere and could be sucking air into the system.

The only way to drain all of the fluids out of the system is to remove the hoses and then disconnect the cylinders and cycle them. Another option is to change what you can and run all functions on the machine for some time and then change the fluid again.
Thanks for the help. Seeing as how it keeps foaming up on me I'm guessing it's probably a leak causing the issue.
 

volkswagenvan

Member
Joined
Sep 16, 2018
Messages
18
Hi Eric.
I`m a little late here but, I have had the same issue with my 440.
Foam in the oil and overflowing just about the same as you. Drove me crazy trying to find the problem!

On Mine, I had to replace the Pintle shaft seals. Not to hard to do. Pintle shafts are what steering arms hook to.
Replace both at the same time. I just removed the snap ring and put a screw into the old seal and pulled it out with vice grips.

Here Is the info.
Seal Part Number 16253-214
Brand nok seals
Size 0.875X1.497X.252
TCV 22.22 X 38.02 X 6.4mm NBR

I am using 10w engine oil in that old system!

Hope that helps!
 
OP
OP
E

Eric lyle

New member
Joined
Feb 5, 2023
Messages
4
Hi Eric.
I`m a little late here but, I have had the same issue with my 440.
Foam in the oil and overflowing just about the same as you. Drove me crazy trying to find the problem!

On Mine, I had to replace the Pintle shaft seals. Not to hard to do. Pintle shafts are what steering arms hook to.
Replace both at the same time. I just removed the snap ring and put a screw into the old seal and pulled it out with vice grips.

Here Is the info.
Seal Part Number 16253-214
Brand nok seals
Size 0.875X1.497X.252
TCV 22.22 X 38.02 X 6.4mm NBR

I am using 10w engine oil in that old system!

Hope that helps!
Thanks. How did you find out that was the problem?. Was there leaking around them?. Also, I'm finding it very difficult finding any parts for this thing. Where are you finding parts. For the seals do I just Google now seals? Again, thank you for any information🙂. I currently have the pump,motor,tank and bracket by the handles ripped out. This is very frustrating for sure.
 

volkswagenvan

Member
Joined
Sep 16, 2018
Messages
18
Lots of research on the internet led me to the seals being the problem.
There was no leaking around the seals and I was skeptical if they were the problem at all. Changed them and everything was instantly good again.
Parts are hard to find. Ebay was my friend for the seals.
 
Top