Erratic Hydraulics

[TRH]

There don't seem to be any leaks on the loader. It's surprising that there is absolutely no leaking fluid on any of the cylinders. All of the connections are old, but dry.

The movement is never jerky. It's very smooth when it moves, regardless of how long the engine has been running.

 

[Gary Sweat]

There don't seem to be any leaks on the loader. It's surprising that there is absolutely no leaking fluid on any of the cylinders. All of the connections are old, but dry.

The movement is never jerky. It's very smooth when it moves, regardless of how long the engine has been running.

Next time you get a chance, raise the loader about half way up, do whatever you need to with the bucket to cause the problem. Then, with the loader still up, grab hold of the bucket and see if you can move it up or down any at all. It shouldn't move but if it is getting air into the cylinders, you will be able to move it to some degree. The more air it has, the more you will be able to move it.

Do this from the side of the bucket just in case it should decide to drop.

 

[SPYDERLK]

If your numbers are somehow accurate, they indicate a 0.85 gpm pump flow at 1000rpm, and 1.1 gpm at 2000rpm....
accordingly flow is by passing somewhere.....go and get the pump tested during pressure (flow meter at both 1000rpm and 2000rpm), so we can get that pump eliminated from trouble shooting...

Perhaps you forgot to multiply by 2 ?
larry

 

[AKKAMAAN]

Perhaps you forgot to multiply by 2 ?
larry

Input and output numbers in yellow...

at
https://spreadsheets.google.com/ccc?key=0AgccLk48zZpwdHE2bjBLekE5cTZWMV9GalcyS0RvZFE&hl=en

Please check so my math is ok!!:thumbsup:

 

[Gary Sweat]

Input and output numbers in yellow...

at
https://spreadsheets.google.com/ccc?key=0AgccLk48zZpwdHE2bjBLekE5cTZWMV9GalcyS0RvZFE&hl=en

Please check so my math is ok!!:thumbsup:

So that would be x2 for two cylinders?

 

[tthopskin@yahoo.ca]

Sounds similar to the problem I have with my bucket dumping. If I let it dump too fast, it will take a couple of seconds to continue moving once the load has emptied from the bucket. Determined that the pump is not keeping up with the cylinders. I think this is caused by the loader valve being to big and lets the oil move through the system faster than the pump can supply oil back to the opposite side of the cylinders.

I will either have to put flow control valves in the lines or go to a smaller loader valve gpm to correct it. This may not be your problem but it sounds similar.

Currently I have a 10gpm valve on a 4gpm pump and 3/8" lines.

you have a air lock in your cylinders hard to get out you have to bleed them

 

[SPYDERLK]

So that would be x2 for two cylinders?

Yup ... double the pump output numbers calculated.