new holland 7703 loader. lifts 1/2 way.

[stevejepsen]

Rear pto and hydro. work just fine. front bucket stops at about 3' high. Good power / lift from the ground to 3'. TC30 is hydrostatic drive, also working just fine.
Check fluids no problem. Checked for obstructions in the housing for the loader, nothing.

When the bucket stops lifting the hyrdo makes a noise similar to when I try to lift something too heavy. Felt hoses when bucket stops, they have plenty of pressure, I can feel it in the rubber hoses coming off the metal lines.

Bucket itself is fully operational, meaning it rotates without noise or issues.

Thought maybe it's a safety switch somewhere. Used the tractor a few days ago to move gravel without issue.

Ideas ? stevejepsen at hotmail.com use @ instead of 'at'

 

[J_J]

Re-seat the QD's to the lift circuits. You have no fluid flow to the lift cyl. The whine is the system going into relief.

If the QD's are bad, you may have to replace them.

 

[Localmotion]

Welcome to TBN :welcome:

First it might help to know what you were doing before it stopped working? Did you try lifting something heavy, have you recently changed any seals or even oil etc...?

If you can hear the hydraulic pump struggling (such as when lifting too heavier load) I doubt it is a safety switch. My guess would be that either something is preventing the loaded from lifting (such as catching on something) or maybe a blockage in the hydraulic lines somewhere. I have had similar with tipping trailers when an o-ring has slipped and clogged the spool block - it then effectively moved with the oil and stayed at the same point in the system so that when I raised the trailer the spoolblock would clog up at the same point each time.

Another thought is whether you have a slave ram (to keep the bucket level as you lift). If so this may have got out of sink and be causing a problem. Easy way to test is to lift until the loader stops, then tip or croud bucket slightly to reduce pressure on the slave. You should then be able to lift the loader a bit more.

My final thought is bent rams - although you should know if this is the case as it will be the result of either lifting something too heavy or an accident!

These are only my first thoughts - there are lots of more experienced mechanics than me here so hopefully someone will have some other ideas... :thumbsup:

 

[stevejepsen]

Last time used it was to spread gravel. Loads were heavy, sometimes too heavy to lift so i would dump some out.

Rams do not appear damaged.

Two interesting new pieces of info.

1: I used to be able to lift the front tires up off the ground using the bucket. No more. When I drop the bucket to the ground and try to lift the front end up I hear the same straining sound from the hydro as I do when I try to lift.

2: I raised the bucket to it's full height of 3 feet up. Then using a 2x6 and car jack tried to lift the bucket higher. I put the bucket into neutral first by moving the control stick all the way forward. I ended up lifting the front tires off the ground. Bucket is firmly limited to 3' high.

I thought it may be a pump problem until I performed the actions in #2. In neutral I should be able to lift that bucket past the current stopping point.

THANKS FOR THE REPLY !

 

[J_J]

Plug a gage into the cyl ports at the lift cyl and try to lift, and tell me what pressure you have.

 

[RickB]

Re-seat the QD's to the lift circuits. The whine is the system going into relief.

.

The QD for the hose connected to the rod end of the lift cylinders is partially unseated or faulty as J_J suggests. Disconnect and re-connect the couplers before doing ANYTHING else.

Simple stuff first.

 

[J_J]

stevejepsen, You said this " In neutral I should be able to lift that bucket past the current stopping point".

In neutral, nothing should happen. All the fluid is just recirculating through the hyd circuits to tank.

 

[RickB]

stevejepsen, You said this " In neutral I should be able to lift that bucket past the current stopping point".

In neutral, nothing should happen. All the fluid is just recirculating through the hyd circuits to tank.

He wasn't in 'neutral'. by his description, he had the lever in 'float' and tried to lift the bucket via external mechanical means. It wouldn't raise because THE OIL CAN'T LEAVE THE ROD SIDE OF THE LIFT CYLINDER CIRCUIT BECAUSE THE QD IS UNSEATED OR FAILED!

Gotta love guys that come here for advise and ignore the easiest, cheapest solution (that often works).

 

[Don87]

Last time used it was to spread gravel. Loads were heavy, sometimes too heavy to lift so i would dump some out.

Rams do not appear damaged.

Two interesting new pieces of info.

1: I used to be able to lift the front tires up off the ground using the bucket. No more. When I drop the bucket to the ground and try to lift the front end up I hear the same straining sound from the hydro as I do when I try to lift.

2: I raised the bucket to it's full height of 3 feet up. Then using a 2x6 and car jack tried to lift the bucket higher. I put the bucket into neutral first by moving the control stick all the way forward. I ended up lifting the front tires off the ground. Bucket is firmly limited to 3' high.

I thought it may be a pump problem until I performed the actions in #2. In neutral I should be able to lift that bucket past the current stopping point.

THANKS FOR THE REPLY !

Your bucket wasn't in nuetral, that's the float position(bucket will float up or down depending on the terrain, but the 'curl function' is still operable.

My first suggestion would be to learn the functions of the equipment.

Not trying to be a smart *ss, but what you are describing is operator malfunction.

EDIT: I'm going to let the first statements stand in case any newbies are watching.

But did I understand your post correctly? You put the loader in 'float' then jacked it up, and raised the wheels off the ground?

If that's the case........JJ is right............change the QD's, they are bad.

 

[stevejepsen]

The bottom inner quick connect was disconnected. I removed the three other connections and the release was clean and had a snap to it. The last one, bottom inside did not disconnect the way the others did. I was sitting inside the connector, but I could see the connector was not closed.

The hose was one of the bucket lines.

I could not reconnect it becuase the line had pressure on it. Once I opened the line (funny story here, dangerous but funny) I will not go into it. Lets say I needed to change cloths afterwards.

Once connected, all 4 of them the bucket worked great./

THANK YOU EVERYONE for the help !! Even the fellow who mentioned operator error

Hope I can return the favor some day on this forum.