# 1977 410 hydraulic help



## Rodeopepper (Dec 28, 2021)

I have an old 1977 JD 410 and recently had something strange happen with the hydraulics I can’t figure out. The front bucket just suddenly got super slow (like in less than 5 min) but all the other hydraulics work completely fine. The back bucket, outriggers and steering respond fine and have plenty of power. I recently replaced all the hydraulic fluid and changed out the hydraulic filter thanks to a hose failure. Before I rip out the control valve for the front bucket I figured I would see if anyone had any suggestions.


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## jd110 (Nov 23, 2015)

You need to check the main pump hydraulic pressure. The steering and backhoe have priority and will work fine when pressure gets a little low. If pressure is good then the priority(pressure control valve) may be stuck. If pressure is low, then it can be adjusted on front pump stroke control valve, or stroke control valve may need replacement. I highly doubt a problem in loader control valve. Believe pressure should be 2300 psi, but I don’t have a book on the 410.


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## Tx Jim (Jul 28, 2020)

Welcome to the TF
I agree with jd110 that hyd stand-by pressure needs to be checked. I also think you need to check to be sure relief valves in FEL control valve are functioning as designed. Tractordata states 410 hyd stand-by pressure @ 2350 psi


https://partscatalog.deere.com/jdrc/sidebyside/equipment/83634/referrer/navigation/pgId/259990




https://partscatalog.deere.com/jdrc/sidebyside/equipment/83634/referrer/navigation/pgId/259952


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## Rodeopepper (Dec 28, 2021)

jd110 said:


> You need to check the main pump hydraulic pressure. The steering and backhoe have priority and will work fine when pressure gets a little low. If pressure is good then the priority(pressure control valve) may be stuck. If pressure is low, then it can be adjusted on front pump stroke control valve, or stroke control valve may need replacement. I highly doubt a problem in loader control valve. Believe pressure should be 2300 psi, but I don’t have a book on the 410.


Well winter got me before I could get the pressure checked but I finally got it. Pressure was 1400psi so definitely low. I looked through my manuals and can’t seem to find the front pump stroke control valve. Can you give me a little help on finding it or what else it might be called in the manual?


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## Tx Jim (Jul 28, 2020)

Stroke adjusting screw on frt hyd pump is item 33 & locknut is item 32 


https://partscatalog.deere.com/jdrc/sidebyside/equipment/83634/referrer/navigation/pgId/213819


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## Rodeopepper (Dec 28, 2021)

Tx Jim said:


> Stroke adjusting screw on frt hyd pump is item 33 & locknut is item 32
> 
> 
> https://partscatalog.deere.com/jdrc/sidebyside/equipment/83634/referrer/navigation/pgId/213819


Adjusted it all the way in (1-1/2 turns) and 1-1/2 turns out but the pressure didn’t change.


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## Tx Jim (Jul 28, 2020)

How many hrs use since hyd filters were changed & suction screen checked/cleaned?
1st thing you need to do is diagnose if trans pump is supplying 5+ GPM of oil to frt pump. Frt pump can't suck oil & must be supplied oil by the trans before any high pressure can be created. Does your tractors hyd pump have a destroking screw or electrically controlled valve?


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## Rodeopepper (Dec 28, 2021)

Just changed the filter within 3 hrs of this happening. Had a hose blow by the hydraulic filter and had to pull it all out. Was laying in a wet field in the 30s so I was more just trying to get it back up and skipped pulling the screen (knew I’d regret it). Everything worked fine after I got it back together for about 3 hours and then the front buck lost all hydraulic power but everything else was fine.


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## Tx Jim (Jul 28, 2020)

What location on hyd system are you attaching gauge to check pressure?


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## Rodeopepper (Dec 28, 2021)

Tx Jim said:


> What location on hyd system are you attaching gauge to check pressure?


At the pump. Right side top plug. Close to where the stroke vale adjustment was at.


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## Tx Jim (Jul 28, 2020)

Checking hyd pressure at pump eliminates other possible valves that could cause low pressure. I suggest to remove supply line from power steering valve, cap pressure port & check pressure again.


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## jd110 (Nov 23, 2015)

Most likely you will need a new stroke control valve. part number RE10712. If you have a destroking screw on top of pump, try turning it in while running and then back it off. If a piece of debris gets in the valve seat, that might flush it out and bring things back to life. Since you mentioned the steering and backhoe seem normal, I suspect you will find flow from transmission pump to be ok, but you should check to be sure.


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## Tx Jim (Jul 28, 2020)

jd110
Does backhoe get hyd pressure in front of pressure control valve? If so pressure control valve could be blocking flow to FEL.


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## jd110 (Nov 23, 2015)

Yes it gets flow first, just like the steering. Original poster said he had 1400 psi at pump. That is not enough to open the pressure control valve.


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## Tx Jim (Jul 28, 2020)

I realize PCV remains closed at 1400 psi that is why PS & BH operate but FEL won't operate.


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## Rodeopepper (Dec 28, 2021)

Rodeopepper said:


> I have an old 1977 JD 410 and recently had something strange happen with the hydraulics I can’t figure out. The front bucket just suddenly got super slow (like in less than 5 min) but all the other hydraulics work completely fine. The back bucket, outriggers and steering respond fine and have plenty of power. I recently replaced all the hydraulic fluid and changed out the hydraulic filter thanks to a hose failure. Before I rip out the control valve for the front bucket I figured I would see if anyone had any suggestions.





jd110 said:


> You need to check the main pump hydraulic pressure. The steering and backhoe have priority and will work fine when pressure gets a little low. If pressure is good then the priority(pressure control valve) may be stuck. If pressure is low, then it can be adjusted on front pump stroke control valve, or stroke control valve may need replacement. I highly doubt a problem in loader control valve. Believe pressure should be 2300 psi, but I don’t have a book on the 410.


Ok I have a new symptom that may help with all this. I decided to get it in the barn to work on and decided to try and jack the bucket up with a 3 ton floor jack. Well I jacked the bucket off the ground along with the entire front end. I tried relieving pressure on the front bucket by pulling back on the bucket control and nothing. Started it and tried again but still nothing. It looks like either I have a stuck piston or something in the hydraulic system is blocked?


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## Tx Jim (Jul 28, 2020)

Will power steering & BH operate?


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## Rodeopepper (Dec 28, 2021)

Tx Jim said:


> Will power steering & BH operate?


Yes BH and PS work fine.


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## Tx Jim (Jul 28, 2020)

You need to concentrate on getting stand-by pressure up to factory spec's. Then that higher pressure will overcome(open) pressure control valve therefore supplying oil to FEL control valve. PS & BH should operate better with higher hyd pressure


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## Rodeopepper (Dec 28, 2021)

Tx Jim said:


> You need to concentrate on getting stand-by pressure up to factory spec's. Then that higher pressure will overcome(open) pressure control valve therefore supplying oil to FEL control valve. PS & BH should operate better with higher hyd pressure


I agree I have a pressure issue but I’m a little confused on why I can’t release pressure from the FEL and raise it manually. I want to get it inside before ripping apart the hydraulics to solve the pressure issue but with the FEL stuck in the down position I can’t do that. I thought lifting the FEL with a jack would have worked if I tried to release the pressure with the lift control but it’s not.


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## Rodeopepper (Dec 28, 2021)

Rodeopepper said:


> I agree I have a pressure issue but I’m a little confused on why I can’t release pressure from the FEL and raise it manually. I want to get it inside before ripping apart the hydraulics to solve the pressure issue but with the FEL stuck in the down position I can’t do that. I thought lifting the FEL with a jack would have worked if I tried to release the pressure with the lift control but it’s not.


Well a little persistence got me there. Finally got the bucket up. So sounds like the first suggestion is to try and pull the stroke control valve? I think I read there was a screen next to that valve. Should I pull that first and check if it is clogged?


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## Tx Jim (Jul 28, 2020)

I've very rarely seen pump filter clogged BUT if you don't check it probably will be clogged!!


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## Rodeopepper (Dec 28, 2021)

Tx Jim said:


> I've very rarely seen pump filter clogged BUT if you don't check it probably will be clogged!!


Ok ran into a bit of an issue here. I figured I’d check what a new pump would cost me and the pump for a 410B doesn’t match my pump. So now I’m a bit confused and wondering if this is even the right pump on here. The pump was definitely changed at some point before I got it. The odd thing is that the manuals pump has a connection towards the front mine doesn’t have. 
My pump








manuals pump


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## Tx Jim (Jul 28, 2020)

1st let me state over the yrs I seen/heard of several hyd pumps being replaced without PERFORMING GOOD DIAGNOSTIC PROCEDURES to determine that the pump replaced was NOT AT FAULT. Pump depicted in your parts photo is a replacement pump with serial # tag not an original hyd pump.


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## Rodeopepper (Dec 28, 2021)

Ok so I ended up buying a rebuilt hydraulic pump, dropped all the fluid, and flushed my lines. The hydraulic filter was totally clean but the transmission filter had a small pile of really fine metal flakes in it. I’m starting to think my transmission oil pump is toast and that debris is coming from it. So 2 questions here. First I was told to check the hydraulic pump inlet pressure to see if it’s getting enough fluid. Second if it turns out to be low I’m going yo have to split this thing to get to the transmission pump. Normally to split a tractor I’d use a splitting stand but this thing doesn’t have anywhere to attach one. The manual says to attach it to an A-frame by lifting points on the head. Anyone have any recommendations on how to split this thing apart if I’ve got to go change that pump?


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## Rodeopepper (Dec 28, 2021)

Forgot to mention it drives completely fine and I’ve had no issue with any power loss from the drive train. Forward and backward work just fine.


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## Tx Jim (Jul 28, 2020)

Fwd & reverse clutches receive their hyd pressure from trans pump therefore I doubt trans pump is source for metal in hyd filter. As I previously stated one should perform good diagnostics """before replacing hyd pump not after replacing hyd pump"".


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## Rodeopepper (Dec 28, 2021)

Tx Jim said:


> Fwd & reverse clutches receive their hyd pressure from trans pump therefore I doubt trans pump is source for metal in hyd filter. As I previously stated one should perform good diagnostics """before replacing hyd pump not after replacing hyd pump"".


Fair enough. The new pump did provide better lifting of the bucket so probably not a bad replacement in the end assuming what ever else is going on doesn’t trash the new one. Also it got the pump outlet pressure up to 1900-2000 psi Vas the 1000 psi the old one was at. Any suggestions as to what else to check? The only other suggestion I’ve got was to check the pump feed pressure but the manual has some sort of flow measuring tool that I can’t seem to find anywhere or get any info on. Based on the schematic of the hydraulic system the destroker solenoid seems like the only other possible source if it’s getting enough flow from the transmission pump.


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## Tx Jim (Jul 28, 2020)

I can fully understand how FEL performance is better with 2X the hyd pressure. Photos below shows 2 types flowraters. Shade tree mechanic trans pump test is to remove hyd oil filter cover of plug if ported filter cover. With clean ,empty container rotate crankshaft/pump shaft with starter for 15 seconds. There should be around 1.25 gallons of oil in container. Have you checked to be sure hyd filter relief valve isn't stuck open? Trans pump pressure should be 155-165 psi


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## Rodeopepper (Dec 28, 2021)

Tx Jim said:


> I can fully understand how FEL performance is better with 2X the hyd pressure. Photos below shows 2 types flowraters. Shade tree mechanic trans pump test is to remove hyd oil filter cover of plug if ported filter cover. With clean ,empty container rotate crankshaft/pump shaft with starter for 15 seconds. There should be around 1.25 gallons of oil in container. Have you checked to be sure hyd filter relief valve isn't stuck open? Trans pump pressure should be 155-165 psi


I’ve read about the bucket method for testing the pump but a couple things are unclear to me. 1. How do you crank for 15 seconds without the engine kicking over? 2. I’m scared to death of the engine kicking over and having no oil in the high pressure pump. 

How do you check the trans pump pressure? I had someone tell me to check the high pressure pump inlet pressure at the fitting below the standby pressure port but it sounds like you’re talking about taking it somewhere else?


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## Tx Jim (Jul 28, 2020)

My knowledge of JD industrial tractors is limited due to my having been employed by an AG only JD dealer for 21 yrs. Disconnecting electrical wire from inj pump solenoid should keep engine from starting. I think one can check trans pump psi at reverser control valve.


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## Rodeopepper (Dec 28, 2021)

Tx Jim said:


> My knowledge of JD industrial tractors is limited due to my having been employed by an AG only JD dealer for 21 yrs. Disconnecting electrical wire from inj pump solenoid should keep engine from starting. I think one can check trans pump psi at reverser control valve.


Well the saga has come to an end. The destroke valve was the culprit. Thanks for all the help as I learned a ton from all your input.

I do have one final question that I think you can help with. I put the test plug in the destroke valve position and started it up with a pressure gauge on. It immediately went to 2400psi … and then 2500 and then 2600 and then I shut her down before I blew a hose or the back side of my pants out. The fluid is cold but that seems a bit higher than I expected and got me kinda scared. Do I need to adjust the destroke control valve to bring the pressure down and if so do I turn it in or out?

Once again thanks for all the help as I’d still be scratching my head on this.


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## Tx Jim (Jul 28, 2020)

Yes you need to adjust the "stroke control valve". Turn screw out for less PSI & ion for more psi.


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