JD Log Skidder 440A- 440B

[steveferg70]

My dad past away and left me his JD 440A or 440B Skidder, it start ok and run very good, the problem is after runnig for about 20min the blade starts to shake and takes a long time to come back up and i start to have steering problmes i check the hydraulic oil and it's full there are some very small leaks under the bottom,been trying to get a manual on the skidder but not able to fined one, called JD they told me the first thing i need to do is replace the the hydrualic lines for the blade, they told me it would be about $3000.00 to replace the lines, BS i've already looked in to that found a place that can make them under $800.00. bottom line i think it's in the pump or something connected to the pump, how could i get the pump rebuild, bad thing for me is that i'm going to have to take it out my self, any help guys Thanks.
Steve

 

[northmanlogging]

greetings, Not real schooled on hydraulicks but it could be the valve bodies, the pistons, the pump, and maybe water in the system or air... should be a hydraulick repair shop near by that could probably get you going a lot cheaper than JD dealer ever could. maybe even the overload valve is sticky?

 

[redprospector]

Sounds kinda like air in the system. There is a bleeder valve on the left side of the steering valve, under the cowel. Turn the steering wheel all the way to the left, open the bleeder valve (a little bit) then very slowly turn the wheel back to the right. If the machine actually starts to turn, you're going too fast...slow down. When only fluid comes from the bleeder close it.
Have you checked the fluid level in the transmission? It only holds 5 gallons, a small leak will run you out of fluid pretty quick putting air in the system. Lift the blade all the way up, and then let it all the way down several times to work the air out of that part of the system (after you make sure the fluid is full).
You have to stay on top of the leaks on 440's, just not much fluid to leak.

Good luck,

Andy

 

[redprospector]

Almost forgot.
There are a lot of better places to buy parts than John Deere. The only parts I buy from them is what I can't find somewhere else.
Last year I put a hydraulic pump on mine. JD wanted $2400 for a rebuilt one, I found one on the internet for a little over $1200.
The way I was told to check the pump was to rig a hydraulic pressure gauge to the down pressure side of one of the blade cylinders (I think it was 1/2" o ring boss, to whatever the gauge is). Try to lift the front of the skidder with the blade. Pressure should read between 1800 and 2200 psi., if less than 1800 the pump needs replacing. Mine was only putting out 700 or so psi.

Andy

 

[floyd]

When was the last time the fluid & filters were changed?