Jump to content

Recommended Posts

I have a 2005 4410 sprayer with just over 5k hours. Previous owner said one hydrostatic pump has been replaced (not sure which one).  Today I started noticing some wonky things, I'll list them in the order I noticed them in. Also the dealer is coming out Monday to diagnose the problem. I figured I'd post it on here and see if any had any thoughts, or if nothing else I'll post what we figure out to help someone else out.

(this all started happening when I was nearing the end of my load, so the sprayer was hot)

#1 I noticed the chemical pump stopping and starting again when stopping and starting driving. (mph, not rpm)

#2 Then I noticed the sprayer being pretty sluggish when using the hydrostatic lever. I was working around poles so I was doing a lot of starting and stopping. It felt kinda like I was spinning out, but I wasn't. And with the speed pot at it's minimum, and the lever at it's maximum, where I used to get 9mph (if I remember right) now I was only getting 4-8mph. (Sometimes 4 sometimes 6 ext,)

#3 I switched fields and noticed I was only getting 26mph, and slowly work it's way up to 29. Where before it was 32 bang on everytime.

#4 With the engine idling, the ladder won't quite raise all the way. But as soon as you rev the engine it'll come right up. 

Which speaking of the ladder, the ladder does not fail the "real" ladder test. (Pot speed 100%, rolling at 5mph, go full speed with the hydrostat lever, the ladder doesn't move at all.)  The sprayer on the other hand takes an eternity to reach full speed. (or 29mph)

I did notice however, when I was rinsing the tank. That when I do the ladder test with chemical pump on, the pump pressure will drop down to 15 or 20psi. Unable to stay where I put it.

We used a infrared thermometer on what I think was the case drain on the wheel motors. The dealer said if the swash plate is messed up it'll bypass a lot more fluid. They were all within 10°(F) though.

We're kind of suspecting the left side charge pump. Because from following lines it looks like that's what runs the chemical pump and maybe the ladder? Couldn't quite tell though.

But honestly nothing quite makes sense to me.

Link to comment
Share on other sites

This all happened at once? The gear pump on back side of the LH hydro has two jobs...#1 job is to supply oil to the product/chemical pump, and #2 send all remaining oil back to/through the cooler and to the reservoir. Should have nothing to do with the ladder/hydros. However, charge pressure for the hydrostat drive operates the ladder when it releases the park brakes, and does its normal job of charging the hydrostat pumps for the drives. Sounds like the charge pressure for both hydro pumps needs to be checked.

Link to comment
Share on other sites

The pump on the back of the RH hydro pump is a variable piston pump for steering, foot/service brakes, and boom folding/unfolding. Unlike most modern piston pumps, it operates at high pressure (usually 2500psi on most sprayers) all the time. That pump is why a CaseIH SP sprayer pulls down hard on the engine starter while cranking. As it builds up to 2500psi, the starter noticeably slows down just before it starts. 

Each hydro pump has its own charge pump. The charge pump pressure from both hydro pumps is connected to each hydro by the small hydraulic hose around the hydraulic filters that connect to each hydro. How they want you to check charge pump pressure on the hydro pumps is to disconnect that hose and cap each fitting that that hose connects to, and then check the charge pump pressure for each hydro(should be about 350 psi). Once you adjust each hydro pump individually, then you hook the crossover hose back up between the hydro pumps. 

Link to comment
Share on other sites

Service tech just left. The left hydro is shot.

When I pulled it out of the shed for the tech, the front right and left rear tires spun. Which sounds opposite of what it should act like when the left hydro goes out. But I guess because the left hydro is out, all the oil from the charge pumps is going there, starving the right hydro of oil.

And the reason the product pump was quitting, is because I was using the "oh sh*t" pedal (as the tech put it) when I was going around telephone poles. ? I guess when you hit the brake pedal it shuts down everything except the engine.

  • Thanks 1
Link to comment
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.


  • Create New...