Problems on home built FEL

[Gary Sweat]

I have been out learning how to use the loader and testing it. Everything with the loader seems to be working alright but two things have shown up that I didn't expect. Tractor is a YM1900.

1) Hydraulic oil from the transmission is seeping out around the shifter boot. I am assuming it is being caused by the return adapter I made in order to route the loader valve tank port back to the transmission. Since I never had this problem before I put the loader return line into the oil fill hole, I'm pretty sure it is the cause. Not sure why or how to stop it. (See photos of the adapter)

2) When dumping a full bucket of dirt, the bucket will speed up once it passes the break over point. Then it will take a few seconds before I can move it further down. I am guessing it is creating a vacuum in the cylinder and the pump can't keep up with the flow rate going out. I am reasonably sure this is not a good thing and could use some help or ideas on how to correct it.

 

[kennyd]

I have been out learning how to use the loader and testing it. Everything with the loader seems to be working alright but two things have shown up that I didn't expect. Tractor is a YM1900.

1) Hydraulic oil from the transmission is seeping out around the shifter boot. I am assuming it is being caused by the return adapter I made in order to route the loader valve tank port back to the transmission. Since I never had this problem before I put the loader return line into the oil fill hole, I'm pretty sure it is the cause. Not sure why or how to stop it. (See photos of the adapter)

2) When dumping a full bucket of dirt, the bucket will speed up once it passes the break over point. Then it will take a few seconds before I can move it further down. I am guessing it is creating a vacuum in the cylinder and the pump can't keep up with the flow rate going out. I am reasonably sure this is not a good thing and could use some help or ideas on how to correct it.

Can't help with #1.

#2-Can you refresh my memory...what valve did you use? It sounds like you are in the regen (regenerative) position on it.

 

[Gary Sweat]

The valve is from Baileynet PN 220-910 and as far as I know does not have regen capability. It's just a straight forward 2 spool, 4 position valve. I could be wrong but I don't remember anything being said about regenerative capability when I bought it. I'm concerned about it possibly creating a vacuum in the cylinder and eventually sucking air into the system past the seals.

 

[wdchyd]

Gary'

#1.....? Is the trans case/reservoir vented..?...it maybe venting thru the rubber boot.....the adapter fittings are very creative, nice work.....would like to see a piece of tubing incorporated in it to deliver the return oil below the oil level to alleviate turbulence at the fitting creating air/foam.......

#2.......Possibly overrunning load creating suction in hyd lines (pump flow slower than load inertia)......flow control may help...Parker F600S Flow Control Valve.....

Hope this helps....

 

[Gary Sweat]

Gary'

#1.....? Is the trans case/reservoir vented..?...it maybe venting thru the rubber boot.....the adapter fittings are very creative, nice work.....would like to see a piece of tubing incorporated in it to deliver the return oil below the oil level to alleviate turbulence at the fitting creating air/foam.......

#2.......Possibly overrunning load creating suction in hyd lines (pump flow slower than load inertia)......flow control may help...Parker F600S Flow Control Valve.....

Hope this helps....

#1... I can add a tube extension as I don't see anything directly below the opening down to the oil level in the transmission. The only vent that I am aware of sits on top of the 3pt assembly. It's a small curved tube. I have not checked to see if dirt dobber's have plugged it up. We have a problem with them here in Oklahoma.

#2... The pump on this tractor only puts out 4gpm which works the loader well enough but may be the problem as you suggest. Would I be able to put the flow control valve in just the bucket lines? The loader goes up and down just fine and a full load does not have the same effect on those cylinders. I don't know enough about hydraulics yet to understand exactly what is going on but I don't like it

 

[wdchyd]

Yes, you can add a flow control valve in just one of the circuits(metering the hyd oil as it comes out of your tilt cyls, ie: meter out) the valve has an adjustment for one way(tilting down) and unrestricted the other direction(tilting up).....

Only one would be installed between the FEL control valve and the tee that splits to the tilt cyls (rod end).....a great valve for tuning and tweaking.....

 

[PILOON]

Wondering if the speed up at breaking point might not be caused by some air lock in the cylinders?

I know that cycling cylinders generally purges things but depending on hose placement there always could be possibility of some 'air lock' in there.

Might try cracking the fittings on the tilt cylinders to bleed out any air.
ie; when fully retracted crack the bottom end fitting and when extended crack the rod end fitting.
A show of bubbles will prove the point.
Either way, nothing to lose. (maybe couple ounces of fluid)

Good luck!

Suggest that placing some rugged object under the bucket and using down pressure til reaching full retraction before bleeding otherwise you'll let in more air and the object is to compress the cylinder fully to force out oir.

Kinda like bleeding brakes on a car.

 

[jlsmith]

Hey Gary, like another member said add a line where u installed the return to go fuller into the trans. This should stop the leak and cut down on the air bubbles which is not good to have in the oil.

 

[Gary Sweat]

Yes, you can add a flow control valve in just one of the circuits(metering the hyd oil as it comes out of your tilt cyls, ie: meter out) the valve has an adjustment for one way(tilting down) and unrestricted the other direction(tilting up).....

Only one would be installed between the FEL control valve and the tee that splits to the tilt cyls (rod end).....a great valve for tuning and tweaking.....

Thanks, I'll order the valve and see if that cures the problem. If I only push the bucket lever about half way to lower the bucket, the bucket will go down ok and doesn't cause the delay in getting it to move again but that is aggravating trying to get just the right position on the lever.

 

[Gary Sweat]

Wondering if the speed up at breaking point might not be caused by some air lock in the cylinders?

I know that cycling cylinders generally purges things but depending on hose placement there always could be possibility of some 'air lock' in there.

Might try cracking the fittings on the tilt cylinders to bleed out any air.
ie; when fully retracted crack the bottom end fitting and when extended crack the rod end fitting.
A show of bubbles will prove the point.
Either way, nothing to lose. (maybe couple ounces of fluid)

Good luck!

Suggest that placing some rugged object under the bucket and using down pressure til reaching full retraction before bleeding otherwise you'll let in more air and the object is to compress the cylinder fully to force out oir.

Kinda like bleeding brakes on a car.

I'll try your suggestion tomorrow. Maybe it is just air. I had to cycle the cylinders the very first time about a dozen or more times until I could stand on the bucket without it moving a fraction of an inch or so. I've been concerned about how to get all of the air out of the lines and maybe this will work. The bucket will raise the tractor off the ground without hesitation but that may not mean there isn't still air in the lines.