JD410 needs some work

[fighthouse]

Hi Everyone!

Been lurking for a few months now ever since my neighbor gave me a great deal on a JD410. Considering I would probably break even if I scrapped it, I was surprised that everything important "works" on it.

I've done some small jobs with it on my property, and would really like to get some things operating better on it to make future jobs easier. The biggest gripe I have with it at the moment is that most of the hydraulics on it are slow. It can take 5-10 seconds to tilt the bucket, and the dipper cylinder was inching along when I used it earlier today. Some of the hydraulics are pretty snappy, like the stabilizers and swing cylinders.

In hopes of improving hydraulic speed, I changed out the hydraulic and transmission filters last weekend, made sure the screen in the bottom of the transmission looked fine, and switched out about 7 of the 20 gallons of hydraulic fluid in it with Hygard. Disappointingly, none of this seemed to improve the hydraulic performance on the machine.

What are some of the other causes of partial slow hydraulics on backhoes? I'd love to get this machine grooving again so I really put it to work.

 

[Delmer]

how much water and rust settled out of the oil you drained? Do you still have the old hydraulic filter? cut it open and check for debris, youtube has lots of videos to show you how. What kind of debris was on the screen? Are the hydraulics smooth, or jerky? How does the front loader operate?

It's kind of the nature that the swing seems fast, but the stabilizers don't seem like they should be fast from what little I know. And 5 seconds seems slow to tilt the bucket. What RPM are you running it?

 

[fighthouse]

Didn't see too much in the old filters, and the screen didn't have any questionable buildup or debris on it. I was actually hoping to find a lot of crud on these items to hopefully have an easy cheap fix to the hydraulic speed.

When I run the hydraulics, I have the engine at full throttle, but I'll have to get the exact number of the tachometer later.

Also, the stabilizers aren't "fast" per se, just faster than most of the hydraulics on the machine. I'd actually describe their speed as normal. The swing cylinders do seem fast, I have to be very gentle with the levers or else the whole machine shakes when it comes to a stop. I can get a video together later of all the hydraulic operations on the machine.

 

[Delmer]

Your swing speed sounds right. I don't know why the stabilizers would be faster than the bucket curl, unless you're low on fluid once you extend the stabilizers, and it's sucking air trying to operate the bucket and dipper?

If you do a video, take a shot of the serial number plate and do a quick walk around, so we can figure out what we're dealing with if there's any questions.

There's two ways to see that filter debris better, rinse it off in solvent and let it settle, or cut a chunk of pleats and squeeze them in a vice to press out the excess oil, then you'll be able to see the debris much better.

Do the hydraulics seem smooth, or jerky? the video might show that, try to catch it on camera if you can.

 

[Willie B]

Do you have a 410, or is there a letter suffix?
I had a 410, worked flawlessly at first, then 1/2 hour later it behaved like you describe. That one proved to be bores too big in the backhoe valve casting.
The fix seems simple; replace two valve sections. JD said No Longer Available. In 2000 the price of the whole backhoe valve assembly was $7000. (close to the value of the tractor).
A hydraulic shop offered to supply an aftermarket valve. They eventually did, it took six months. When it arrived each section was 1/4" narrower than the original. The joystick mechanism wouldn't fit. I spent 1-1/2 days building a new one to fit.

This spring I bought a 410C. It behaved much like the first. That proved to be like the first in that the needed part is NLA.

 

[fighthouse]

Here's a video of the hydraulics in action. All of them were run wide open, except the boom swing cylinder. As you can see, most of them run slower than they should

 

[mg2361]

On the left side of the hydraulic pump is a solenoid called the destroke solenoid. Remove that to see if any of the o-ring's are blown. Also make sure there is no voltage to the solenoid while the engine is running. If all that is good then you need to check charge pressure and standby pressure.

 

[fighthouse]

Destroke solenoid o-ring looks good. I'll try to test the voltage on it with a multi-meter later.

How do I check the charge pressure and standby pressure? I see some tutorials on youtube, but they are for smaller and newer tractors.

 

[Delmer]

start at 23:27

This is for ag tractors with a similar pump and system design. Yours obviously won't have a rockshaft or SCV's or PTO clutch, but you can get the idea of how the system works from the manual. The JD manual for your backhoe will show how to test the same things with better pictures, and detailed lists of tools and adapters needed.

On your front hydraulic pump, there should be two ports, one will be a medium pressure charge oil from the transmission pump if you have a powershift trans (or maybe a separate gear pump mounted on the front of the radial piston pump). That will be less than 300PSI. The other port will be less than 3,000 PSI, so use a 3,000PSI or higher gauge to check before you hook up a lower pressure gauge. You'll check the standby pressure with nothing operating, but the charge pressure you want to see what it drops to when you have somebody operate the backhoe functions.

 

[fighthouse]

Went out today and got a couple of things to try the hydraulic pressure. Going by the TM, the outlet on the pump should be 3/8"

Went to the some local tractor store, and picked up a gauge, some hose, and connectors. When I got home to try it out, the Outlet connection looks way smaller than 3/8", maybe 1/8". For reference, the gauge is 1/4" and the hose connection is 3/8"

Is it possible that the pump has been modified to have smaller connections for these ports? Or am I missing something way obvious (wouldn't be the first time )?

 

[Ed L]

3/8-24 unf pressure tap they are referring to is a straight thread not a pipe thread (npt).

 

[fighthouse]

That makes sense - I was working with oranges when I should have had apples.

I'm trying to look online for other components to make it work, but having a harder time than I thought. I can return the hose and the fittings I picked up, but I still want to work with the 1/4" npt pressure gauge I have.

I figure I need some type of 3/8-24 connector for the pump, probably a 1/4" hose, and connectors on each end of the hose to go to those two items.

 

[chroniekon]

I have a 310, but the same pump or at least the same type with the two ports. I had the same problem finding the right fittings, so I made my own. Pretty simple really. I welded a 3/8-24 bolt to the big end of a 1/2 x 1/4 NPT black iron bushing, drilled a hole lengthwise through the end of the bolt, found an o-ring to slide over the bolt. Works like a charm.

 

[Delmer]

https://www.discounthydraulichose.com/mm5/thread_guide.pdf

go to page 6, that's a 3/16 or -03 O ring boss fitting. You can get adapters there for under $2, I'd go to 1/8" npt female and get an 1/8 to 1/4 coupler and then you can use a grease gun hose between them.

 

[fighthouse]

Ok, I think I have the parts I need figured out.

I will also get a grease gun hose from amazon that has 1/8" NPT male connections on both ends.

 

[Delmer]

You sure that coupling is rated for 3,000 PSI ?! If you don't have a grease gun hose, just order the correct stuff if you're ordering already.