Hi all, yes, new guy here. I'm a retired mechanic that admits he doesn't know everything. I have a JD 325 Diesel Skid Steer That starts easily, idles and runs well, Hydraulics all work ok at idle. Problem I'm having is that when I increase the throttle and put a load on it, (mostly driving) the machine wants to hop like crazy! The problem came suddenly. I can throttle up at a standstill slowly all the way to 3000 RPM's, but as soon as I try to move, no matter what the engine speed, it bucks like a bronco. Any ideas or comments are appreciated. Sorry for the lack of info. I will get any model, serial, etc. numbers at the garage tomorrow. Thanks again.
Welcome to HEF Bob ! Yes, please provide a serial number. Did you check all your steering linkages for issues? The lever on top of the pumps that use a pinch bolt, is it tight on the swash plate shaft?
Thanks for the welcome! Serial number is: T00325A122815 I checked the lever on the pumps and linkages as you suggested. All tight. The problem I have is more like the engine surges up and down when trying to drive at over 1500 rpm. Thanks again for the suggestion. Bob
Like a rabbit? You say. Mr. Grute approves of this thread.
LMAO! Well, not exactly. Engine speed revs and drops constantly till I lower the throttle. Nice picture!
If you are experiencing what we call the "machine gun hunt", which only occurs in the 5030 engine, which is what is in your machine, then the fix most likely will not be cheap. And worse, temporary. Maybe post a video showing the hunt to make sure that we are dealing with an engine issue and not a travel issue. For starters, the fuel pressure will need to be checked. Tee into the line between the fuel filter and the block. Should maintain a minimum of 10 psi at all speeds and loads. If it does not, then change the fuel filters and try again. Also, the fuel system should hold approximately 4 psi for 15 minutes after shut down. How many hours are on the machine?
Machine Hours are 3200 I'm trying to upload a couple videos to show what it does but site tells me they're too large. I'll try to shorten them and keep the needed parts and post in a bit. Thanks
I'm going to have to work on these videos. one is only 6 seconds long and still says too large. Sorry Will post later. Thanks again for putting up with an old guy.
Here are links to videos (sorry for the poor quality) for our John Deere 325 Skid Steer surging.
The engine sounds like it has quite the fuel knock. Will it surge just at fast idle no load? Video of the engine noise at idle - no load, fast idle - no load please. If it will surge at fast idle show that too (no load).
Thank you. I will do that tonight or tomorrow. My daughter is having knee surgery right now and I'm the therapy dog for the day.
Ok, John Deere 325 Skid Steer VIN, Engine Hours, Machine Idling w/no load, Machine 3000 RPM w/no load. My daughter is home. gonna be a loooooonnnggg recovery. As always, Thanks to all for any and all help and suggestion. Especially MG2361. Appreciate it all.
If you have good mechanical skills, then follow the procedure I PM'd you. My opinion is after hearing your engine, it sounds like it will need the pump/injector assemblies. Lets hope it is one of the simple fixes. If it comes to pump/injectors, then that is not a job you will be able to do. There are special tools and procedures to set the timing on the individual pumps. And, you would need to have someone who knows what they are doing. They need to be set within .001" of each other by spec. I'm OCD, I set them to .0005" of each other. Even most dealer tech's today are not familiar enough on these engines or meticulous enough to work on these injection systems. I have seen new pumps fix the issue and run forever, and I have seen them fail again in 1500-2500 hrs. I think the reason may be maintenance practices and/or the quality of the fuel being used, plus just a bad design. So again, lets hope for a simple fix.
Thank you. I will follow your procedure on Monday. They use the red off road fuel here. Could that be the fuel knock you heard?
The off-road fuel is fine. Same as the on-road, just a different color. When I mention quality, I mean no water in the fuel, algae, asphaltene, sediment, dirt, etc. The fuel knock is usually a sign of an issue on those engines. Those engine's are "rappie" to begin with, but yours is a little more than usual.
Gotcha. Thanks. I'll check out the tank also. Will be doing those other procedures tomorrow.
Sorry for the delay in getting back to this thread. Daughter had to be readmitted to the hospital and it's taking a toll . I will get back to this thread as soon as I can. Thanks
From my family to yours, wishing your Daughter a speedy recovery and hopefully all works out well. We must look after our family first.
Thank you. They certainly do in my book.
ANY UPDATES ON THIS WILL HELP mine is doing the same thanks Todd 1-608-988-0110
Helpful information that you mentioned above. I have same machine (John Deere 325 Skid Steer) experiencing same problems. Would you please share the procedure with me that was shared above before I send loader to shop for injector pump/nozzle assembly replacements? I have changed filters, checked for fuel restrictions and seems to be narrowed down to worn injectors or timing issues. Thanks.
Welcome to HEF aej0014 ! Check your messages.
Awesome! Thank you for the diagnostics information. You've been a great help!