We bought a cat d5 lgp, 26 pads, 6-way, A/C, heat at a sale a few weeks back and think their is a problem with the way it performs. The machine runs great and does not ever get hot. On flat ground it performs as expected but if you attempt to push up hill on a grade it seems to barely have any power at all. It will barely pull itself under no load up a 2/1 grade. The tracks never slip no matter what you a pushing. After starting the machine at any time you have to "double clutch" for lack of a better term the decelerator before it will move at the proper speed. We have added hydraulic fluid twice in the last two weeks but the machine shows no sign of any leaks. We have been told that this could possibly be a pressure valve. I would appreciate any info that someone may have on this problem.
Not that I can help you much but I'm guessing this is a G?
Yes, D5G
Just want to clear this up. You have lots of power pushing level,or down hill but not up hill? Does your machine have an injector pump with lines or a high pressure rail? Later Bob
Do you change the speed setting when pushing the heavier load up the hill?
The double clutch seals the deal. Then engine speed needs to be calibrated to the pump speeds. Had a buddy with one doing the same thing. Machine would never spin the tracks into a pile just kind of bogged down. Calibrated it and the dozer is a beast now. Never boggs or slows now. Essentially the governor control cable has gotten out of sync with the computer. Engine is telling ecm it is at one rpm and pumps are telling it they are at a different speed. It does not have to be very far out of adjustment to cause this problem. Unfortunately you have to calibrate it with ET (Cat Diagnostics).
My D5G does this to a certain degree. It doesn't loose significant power but when changing directions or pushing into a pile it will slow down slightly and a "double clutch" on the decel gets it back in line. Thanks for the info caterpillarmech.
Thanks for the info, this really sounds like the problem we need to look at.
Only a little.
Pushing level is ok but not what I would expect from this machine. We have a 650 JD that puts it to shame. Not sure about the fuel rail, will have to see.
As above the thing you need to be aware of is that to successfully calibrate the machine requires a laptop equipped Caterpillar Electronic Technician software. Someone else may correct me on this but I think it's possible to do it with both customer & dealer versions of ET. If that is the case then it doesn't necessarily need a dealer to do it, an independent mechanic with ET could do it just as easily.
Can someone verify that the customer version is capable of this? Thanks for the info.
A friend of mine has the customer version. I will check with him to see but, I am almost positive he is able to do calibrations. Once the calibration is done, you will not believe the difference it will make. My buddy told me later that his was an entirely different machine after I calibrated it.
We can do a certain amount of calibrations with our customer version of ET. I was reluctant to say this particular calibration could be done because I've never had our ET hooked up to a D5G.
I changed the drive filters and the fuel filter 2 days ago and have noticed considerable improvement in performance. However I believe that I have discovered the problem with the "up-grade push" bogging out. When I removed the fuel filter and positioned the new filter to fill up via the fuel pump, we turned the key on to activate the fuel pump and only had a very small bubbling amount of fuel drizzling from the pump. The machine had around 3/8 of a tank of fuel remaining according to the gauge. We topped off the fuel but still have only a slight flow of fuel from the pump. It is my thinking that the fuel pump is going bad and during the up grade pushing the fuel pump is not able to draw fuel from the tank after the fuel level drops below 1/2 of a tank thus bogging the machine. After changing filters and topping the fuel the machine will now spin the tracks as it should under a heavy load. Now one problem still exist, 75% of the time you must still "double clutch" the decelerator in order to get the machine to move at the correct speed. I have noticed that during for instance finish grading when you mostly use the speed control buttons their is never any problem, however if you are doing things that constantly demand use of the decelerator like land clearing their is a problem. Without knowing what exactly provides input from the decelerator to the ECM I feel that this is where the problem remains. I am not sure that it is just calibration, I think some unit or sensor is bad.
Customer et will do it
thanks for the info
Sweet. All you need now is someone with ET.
Im in northwest GA
After running my D5G Friday, I need to calibrate it.
The decelerator input is the engine speed sensor(on the crank). The pumps and motors have output speed sensors as well. This has to match within 50 rpms. I am glad you found the filter issues but, it stills needs calibrating if you do the double clutch to get desired movement.
Thanks very much to everyone that has helped with this issue. I do have one more question that maybe caterpillarmech or someone else can answer for me about the calibration issue. Is this a thing that can just happen at any time (getting out of sync with each other) or is it generally caused by a underlying problem. If this is something that is going to have to be calibrated on a regular basis I think we need to go ahead and buy the ET so we don't have to haul the machine so far to a dealer. Are there other issues like this that need to be calibrated on a regular basis that would benefit us to buy the ET?
Awsloan, my D5 has 4100 hrs on it and has just started to do it over the last year gradually. How many hours on your machine? It's probably just a maintenance item.
Please let me know the results you have after calibration.
Besides the CAT dealers, can the ET be purchased at a better price from other sources? Can the protocol adapter and cables be purchased separate from the software or is this always a package deal?
I will. Probably end up calling the dealer and have them come out but I've got to finish up a building pad first.
going to have to check, can't remember right off, may be the old age thing this morning!
Does anyone know if the D5G has a AutoKickdown Switch? If it does, could this be affected by the decelerator pedal? I have noticed that when I press the decelerator all the way to the floor and change directions the speed is usually correct, but if I only press down maybe half way the speed is about half of what it should be until I press it again. I may be way off here on the function of the AutoKickdown switch so correct me if I am.
Calibrations are something that generally are classed as "when required" which means if you change something on the electronics like a sensor or change a mechanical component such as a transmissison the calibration should be performed. I wouldn't class calibrations as something do do every "X" operating hours for example. The problem with ET is that it's expensive, not only to buy initially but after that there's an annual subscription to pay and you're into big dollars. Far cheaper if you only have the one machine to find an independent heavy equipment mechanic who has ET, or even pay a dealer to do it as and when you need it done. It's probably no more than a 30 minute job.
Nige I think the clutch fill calibration should be an annual service to compensate for disc wear. That said many shops install overhauled trans and don't calibrate them. Guess it never occurs to them. Later Bob
Bob, I agree with you. There are certain things on our machines that we re-calibrate as a PM item to compensate for wear or even to act as a diagnostic check. A couple of those are 994 converter Impeller Clutch (wear compensation) and 16M transmissions (diagnostic). On the 16M we can't keep #2 clutches in them more than about 4-6000 hours. What we've found is that even if a tranny hasn't failed if #2 clutch won't calibrate (the calibration procedure times out before the clutch engages 100%) we can guarantee if we pull the transmission the clutch will be worn almost to the point of failing. At least that way we can class the component as "removed before failure" and count the machine downtime as planned rather than unplanned. We're still waiting for the definitive fix from the factory that gets us to a minimum 10,000 hours, until then all our transmisisons are being overhauled FOC under Goodwill. We had to educate the local dealer into upgrading software, erasing logged diagnostic codes, & doing all the relevant calibrations as an SOP when they were overhauling machines for us. To be fair to them they picked up on the principle pretty quick and now it's very rare a machine comes back to us with anything whatsoever needing doing on the software/calibration side of things.
I agree with bo on the trans cal for trans and ive seen a lot of speed sens. reading off flywheel that need to just be taken out and cleaned
Problem solved. The problems that I have described throughout this entire thread were caused by a little black muck sucked up into the fuel filter housing. We removed the pump and the filter and blew out the housing and now everything is working just great and as it should. No more "double clutching" the decelerator and machine speed is always correct. After learning some things in this thread I think that the ecm was seeing the throttle position was not jiving with the engine speed and degrading the output because it saw a problem. When the decelerator was double clutched it gave the fuel pump a moment to catch up. We discovered the muck problem after the machine performance got so bad that it was impossible to continue to work it. I hope that this thread will help someone in the future that has a machine acting up this way.
Good to hear you got it solved. Sometimes checking the simple things first gets overlooked.