L4630 3 pt slow to lift

[Bill in the U.P.]

Hello. My first post here. Very glad to have found this site. I have a L4630 GST. My 3 point has a time lag in the lifting operation. I am using a back blade for snow removal. It is now necessary to come to a complete stop, lift the lever and wait for the back blade to rise. Maybe 3 to 5 seconds or more. I have the valve below the seat to full open. My hydraulic fluid level is good having just replaced a quick connector at the back of the tractor that had leaked out almost all my hydraulic fluid before I noticed. The FEL seems to operate fine. Thanks in advance for any help you can offer.

 

[GreensvilleJay]

have to ask how COLD is it where you are ? My D-14 hydraulics need to get 'warmed up' before the rear blade goes from 'snail to rabbit mode'.
also check the specs on the oil you used ! some aren't good in cold temps.

 

[Bill in the U.P.]

have to ask how COLD is it where you are ? My D-14 hydraulics need to get 'warmed up' before the rear blade goes from 'snail to rabbit mode'.
also check the specs on the oil you used ! some aren't good in cold temps.

Thanks for the reply. I'm in the UP of Michigan so it will get below zero later in the year but so far into the teens. This is my 3rd winter with the tractor and this is a new issue. I'll check the fluid I bought from the local Kubota dealer.

 

[lugbolt]

and what hydraulic fluid is being used? Super UDT or cheap stuff? It makes a big difference. Also how long's it been since the filter's been changed?

hydraulic power (force) is due to pressure, if you have plenty of lifting force you have plenty of pressure. Hydraulic SPEED is a function of the amount of fluid that is pumped, IOW, flow rate. There are things that can reduce the rate of flow going to the 3ph. An internal leak can cause it. So can a mashed exterior hydraulic tube.

 

[pokey1416]

Welcome Bill from the warmer part of the state. Lot's of great info on OTT, I'm definitely not an expert but when you added fluid is it possible your still low and have some trapped air that has to work out?

 

[Bill in the U.P.]

Welcome Bill from the warmer part of the state. Lot's of great info on OTT, I'm definitely not an expert but when you added fluid is it possible your still low and have some trapped air that has to work out?

Thanks for the welcome. You might be right. It was fine before the whole leaky coupler and adding fluid event. So, maybe it will get better with use?

and what hydraulic fluid is being used? Super UDT or cheap stuff? It makes a big difference. Also how long's it been since the filter's been changed?

hydraulic power (force) is due to pressure, if you have plenty of lifting force you have plenty of pressure. Hydraulic SPEED is a function of the amount of fluid that is pumped, IOW, flow rate. There are things that can reduce the rate of flow going to the 3ph. An internal leak can cause it. So can a mashed exterior hydraulic tube.

Using the Kubota brand hydraulic fluid the local dealer recommended. I suck at mechanic work so rarely do service stuff (embarrassed emoticon here) - so I've never changed filters (oil or hydraulic). I did purchase Kubota oil and filter last week and plan on getting to that soon. I will also attempt changing the hydraulic fluid and filter too. Which brings up another question about service manuals. I really need to get one (Idiots Guide available?). But seriously I'm open to suggestions about a SM

 

[pokey1416]

I bought the work shop manuals (WSM) for tractor, loader, backhoe on pdf from the dealer. Came on a CD and is a must even for us novice mechanics. I think I paid $210 for all of them (including the operators manuals).

They're model specific so none of mine is going to help you or I'd include some pics etc in this thread. There's a different site that people mention on here once in awhile that has manuals too and I thought there wasn't a charge but I could be wrong. I had a leaking hose in BH when brand new and service tech came out and put in half gallon of UDT2 after tightening hose. I still had to top it off occasionally after that for awhile. It's amazing how fast a pressure leak can lose. Anyway, after awhile it was fine on keeping level. I did have to top a little when I took BH off this fall and installed all 3PH linkage and my ballast box.

 

[Bill in the U.P.]

An update. I think you may be right about air working out pokey. I ran the tractor for awhile yesterday and the 3 pt lift response seemed to be improving as time went on. I'll keep an eye on the HF levels as well. Happy New Year to everyone.

 

[whitetiger]

An update. I think you may be right about air working out pokey. I ran the tractor for awhile yesterday and the 3 pt lift response seemed to be improving as time went on. I'll keep an eye on the HF levels as well. Happy New Year to everyone.

Check the suction hose at the hydraulic pump for cracks or pinholes. I have found several of them sucking air there causing a slow response of the steering, loader, and or 3 point.
The 3 point knob that you referenced is for Rate of drop only, it has no bearing on the lift.