4240 hydraulic issues

Cduke88

Member
Good morning. I have a 4240 that has been acting up for awhile. I changed the screen and filter Friday and had quite a bit of shavings in it. I added oil and it worked for about 2 minutes. No hydraulics would work. Steering power lift and bucket were all dead. I noticed that before it quit that the power lift would l if the motor down when going down. I adjusted the pressure screw on the pump and it works somewhat. Maybe 25 percent. The weird thing to me is when the powerl off is down I have no hydraulics. When I raise it they somewhat work. I am thinking it is the pump but want some advice before a spend more money on this money pit. Thank you.
 
The filings you found are in the system,,and probably has the stroke valve stuck,,some times you can back the stroke valve screw (
the pressure setting screw under the front pump) out a bit while the tractor is running and then screw it back in and it will
jigger free...but the bottom line is you are going to need to find where the filings are coming from and fix that and clean the
filings out of the system, magnets can help..
 
(quoted from post at 11:33:20 02/18/18) Good morning. I have a 4240 that has been acting up for awhile. I changed the screen and filter Friday and had quite a bit of shavings in it. I added oil and it worked for about 2 minutes. No hydraulics would work. Steering power lift and bucket were all dead. I noticed that before it quit that the power lift would l if the motor down when going down. I adjusted the pressure screw on the pump and it works somewhat. Maybe 25 percent. The weird thing to me is when the powerl off is down I have no hydraulics. When I raise it they somewhat work. I am thinking it is the pump but want some advice before a spend more money on this money pit. Thank you.

That pump screw is a de-stroker. to allow easier cold weather starts by taking the front hydraulic pump out of stroke.
It has only two positions . Dialed in to de-stroke while starting. The rest of the time backed all the way out onto it’s back seat so it doesn’t weep oil.
Has anyone allowed anything other than Hy-Gard to be in the transmission ?
 
We use only hygard oil. After unscrewing the screw on the pump and screwing it all the way back in and backed out 2 turns it works about 25 percent. I am leaning towards the hydro pump being bad. It's just weird that with the power lift down it shuts all hydraulics off.
 
I'm not talking about the de-stroking screw,, I'm talking about the pressure control valve screw "Under" the pump..backing it off and then running it back in while the tractor is idling can loosen the stroke valve from what ever is holding it open,,"some times".. The priority valve located on the right front corner of the rockshaft, where the pressure line goes in will shut down the rear hydraulic flow when the stand by pressure dips below 1750 PSI,,,and if the stroke valve is stuck your pressure will drop.....and if you have filings floating around in the system there will be a lot of problems developing...and the primary source of filings is the brakes...it will be worth the time to pull the final drives and take a look...
 
That's right. Unopened the pressure control valve screw until it almost fell out. Started the tractor then shut it down and screwed it almost all the way in. And I got some movement but not much.
 
Then the stroke valve is "stuck" real tight,,you can get them in and out with out removing the pump,,but it's ornery.. the plug on top needs removed as well as the large plug holding the valve in,, the a 5/16" bolt or punch in the top hole and drive out the valve, it will be 2 piece. And you will get oil in your arm pit,,so have some one else do it while you hold the light ;^)
 
How hard is it to check the brakes? Does the tractor have to be split? They work good but something is making shavings. Not all super big but a bunch of finer ones. I guess that would be the first step?
 
You need to pull the final drives,,if you have a cab remove the rear cab bolts and lift and prop it up a bit,,about 2 inches,drain the oil of course, you can use a floor crane as a cradle, jack the one side of the tractor up ,,slip the floor crane legs under the tire, and use the boom to steady it all, remove the final drive bolts and roll it apart,, I have a wheel dolly here to make it easier,,and it seems like I pull a few every week,,so practice makes perfect...getting rid of the filings is the big problem,, you can't do much about them from the final drive side,,you can pull the PTO outer and inner shaft and reach into the differential area to swab out some,,pulling the plug on the lower clutch housing drain will get some too,, I get what I can with swabbing and magnets and then stash some magnets into where ever I can,, I use Cow magnets they are small and strong,, I like the square ones that you can get from Tractor supply,, about #3 apiece ,they are about 3/4" X 2 1/2"
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If your brakes are bad ,,you can get A&I pads and rivets to replace them,, Deere wants to sell you a high priced up-grade...Tell us what you find and I can help you with ideas for relining them..
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I will definitely let y'all know. Is it rare that the pump itself goes out? What do the brake shavings actually look like? I'm trying my best to narrow this down as far as I can before having to spend money. [/img]
 
There will be shiny pieces of metal and some black soft pieces of brake lining,, the brakes are the number one source of filings. I pulled the final drives on a 4630 last week that had a axle seal leaking and the pads were just about to tear loose..we did both sides on it. I pull a lot of them apart just to look,,it's the only way to know for sure.
 
By power lift are you referring to the 3 point? Did you happen to take the plug out of the differential that is behind the right hand SCV? It takes a half inch extention and breaker bar to remove the plug, once out shine a light in the differential when the 3 point is up and then down to see if there is oil just trickling out of the rockshaft valve or massive leak and oil spraying all over in there while the tractor is running. Also does this tractor have lift assist cylinders on the three point? Also feel the rockshaft valve while the tractor is running to see if there is a warm/hot spot anywhere on the housing.
 
First off thank y'all for your help and advice. Whatever was stuck or plugged up freed itself and hydraulics are working again. I am gonna have the brakes replaced and fix it right. Sometging is causing thr shavings and after talking in here i believe yall are right about the brakes. I live south of San Antonio.
 
By the way. I got a quote of 2000 to dobrakes. Does that sound reasonable?I really don't have the proper tools or time to try myself.
 
(quoted from post at 16:16:12 02/19/18) First off thank y'all for your help and advice. Whatever was stuck or plugged up freed itself and hydraulics are working again. I am gonna have the brakes replaced and fix it right. Sometging is causing thr shavings and after talking in here i believe yall are right about the brakes. I live south of San Antonio.

Just wondered . The term "Lift " or "Power Lift" instead of "rock shaft" or " three point hitch" tends to be a European or British Commonwealth phrase.
 

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