DF-354 Dongfeng Tractor Hydraulic Problem

[JohnS]

"I purchased the tractor with a Helpmate-II loader. The loader is made in the USA. The problem with having the dealer fix the problems is that I bought the loader on EBAY and the dealer is about 350 miles from where I live. There are no dealers close to where I live that can work on the tractor."

Assuming you meant to say, "purchased the tractor and you added the fel from a purchase on ebay." OK, that makes a BIG difference. I wouldn't hold the dealer responsible, given they did not install or hydraulicly plumb the loader. Also, the comments above about the welds, etc, shouldn't have been directed to be a fault of the dealer. If on the other hand, you bought the fel from ebay, and brought the fel to them, and they installed, they probably bent too far over backwards, and took on too much risk (unless they sell with same fel). The other misc stuff, I hope the dealer has sent you new parts.

I am not familiar with the DF354 hydraulic plumbing, but it sounds like your FEL is connected straight to one of the pumps, which could cause dead heading and the overheat and failure of the pump. While it is the way Jinma plumbs their 200 series, for their ZL20 FEL, it is not the prefered way. I am also not familiar with Helpmate FELs. If it is a USA made FEL, I suspect that the QDs don't mate well with the Chinese QDs. I would change out the chinese to match the Helpmate QDs. Did Helpmate provide any hyd plumbing info? I assume they had to have least mounted one to a DF354, to make associated brackets, etc to fit.

 

[RonMar]

The loader plummed right after the pump shouldn't cause a deadhead problem if the safety relief on the loader control valve is set properly. On an open center hydraulic system, you either need a safety relief valve right on the pump outlet before any control valves, or on each control valve that is plummed into the system to bypass fluid around that valve in the event that valve/cylinder is stalled/overloaded. Something has to be first in line, it might as well be the loader

John I completely agree with the missmatched Quick Connects.

LP15404, I would hazard a guess that it might be what damaged the original pump. Slight differences in construction and materials from different maufacturers, or the spring in one half of the pair is stronger/weaker than the other and dosn't allow the check ball to fully open causing a restriction or even a blockage in the line at the QC union. Since I doubt there is a safety relief on the pump outlet, a restriction here leaves the fluid no where to go(dead end or dead head) and the excess pressure kills the pump. That is why you never disconnect the QC's while the engine is running, or try to run with them disconnected. I would reccomend that you replace ALL the QC's with ones from the same manufacturer, either chinese or domestic, just make sure they are all the same. You could also remove ALL the check balls from ALL the QC's in the system before you install and run the new pump.

Erratic operation can sometimes be attributed to air in the system. Since you said both pumps draw oil from the same supply and your steering has also acted up, I would look for any possible point on the suction lines where air might be drawn into the pumps. It is also possible that damaged seals in the pump itself could allow air to be drawn into the system.

 

[lp15404]

I removed the quick-disconnect coupler and took it to my local Car Quest store and they were able to give me a connector that works for $4.89. The coupler is not a quick-disconnect. I just put it on and it appears to be working ok. At least I don't see any leaks.

After I got the connector put back together, the UPS truck pulled up and they had a pump from my dealer. The dealer told me that they were shipping the pump on Monday June 19, but it was actually shipped on Friday June 23 according to the tracking information. The pump that I just received from the dealer is not a CBN-314 but it is a CBT-316FL2. It does not even come close to being the right pump. The mounting holes are a inch further apart than the CBN-314 pump on my tractor. The pump does not appear to me to be new.

 

[lp15404]

JohnS, I did purchase the tractor from the dealer with the loader already installed. The dealer has replaced the rotation speed sensor, the voltage regulator and the oil pressure sensor. The rotation speed sensor does not register properly. It will not go any higher than around 1800 rpm.

I don't see any reference in my Helpmate loader manual to a pressure relief valve. There is a reference to a hydraulic bypass adjustment on the loader controls that regulates hydraulic pressure. I have not attempted to adjust it.
I don't know very much about tractor hydraulics and I have no equipment to check pressures etc.

I will check to see if I can find where air might be getting into the hydraulic system.

 

[DwayneB]

JohnS, I did purchase the tractor from the dealer with the loader already installed. The dealer has replaced the rotation speed sensor, the voltage regulator and the oil pressure sensor. The rotation speed sensor does not register properly. It will not go any higher than around 1800 rpm.

Two things come to mind on the RPM, linkage at the injector pump not letting it open all the way or valves too tight and need adjustment. Take the linkage loose at the pump and see if it will go more open with the linkage off. Tractor not running for this test. Could just need adjustment. If not then check the valve clearance. The 395 is a good engine and the procedure for adjusting the valves is documented here http://ctocf.proboards54.com/index.cgi? or here http://www.ctoa.net/

 

[lp15404]

DwayneB, Thanks for the tips on RPM. I am not sure if the engine is not running fast enough or if the speed sensor is the problem. The original rotation speed sensor had a open winding. I received a new one from the dealer, but the connector was not the same as the original one. The connector looked the same on the outside, but the pins were not in the same position as the original one. I removed the connector and put the old connector on the new speed sensor and it seemed to work, but with the throttle wide open it only read 1800 RPM. The dealer sent me another rotation speed sensor, but it was the same as the previous one he had sent. I put it on the tractor and it still would not register more than 1800 RPM. At first I adjusted the sensor 3/4 turn back from where it hit the flywheel. Later I adjusted it so that it is only 1/3 turn from hitting the flywheel and I still had the same result. I also tried reversing the wires to the speed sensor with no change in symptoms.

 

[JohnS]

Ronmar, the problem is the QDs come before the relief valve in the loader valve. There should be some relief on the pump, or the QDs come past the first relief. Someday they will figure it out, and change the design.

lp15404, your problem is not air. It is a pump that is pumping oil, and there is no pace to pump oil to. The QD spring was probably causing the blocking. While some do leak, the bigger problem is blockage. Run the tractor only at low rpms, until you are sure it is fixed. You should be able to detect the deadhead load on the engine, and be able to shut it down, before blowing another pump. Be quick though. It doesn't take long to overheat and melt internal o-ring, crack pump case, or blow the seal on the pump shaft.

 

[Boltonpower]

Sorry to hear about the issues. On the couplers. Don't assume the threads
are metric. The coupler is a knock-off of an IHT #1 but not quite. The American coupler and the Chinese won't quite lock up. Jinma puts 1/2" NPT threads on thehoses so they can easily be replaced. The KOYKER loaders come with the IHT'sand we just swap them out. Many of the parts on that TY-395 engine are common to the Jinma TY-395 so jinmaparts.com or Nortrac are good sources. They usually seem to ship from stock.

Regards
Graham

 

[Soundguy]

I see them darn QD's coming into play again. Too bad there is uh.. no 'standard' to build them too...

Soundguy

 

[3RRL]

I see them darn QD's coming into play again. Too bad there is uh.. no 'standard' to build them too...

Soundguy

I presume a "worldwide standard"? That would be good. Right now it just depends "whose" standard is being used.