I had the local cat dealer work on it and they say they cant find the problem. When operating the machine, it will run great for a few minutes then it goes into what feel like a reduced power mode. What to look for?
Do you mean engine or travel speed, serial number if possible
both the idle and the travel speeds are limited. I don't have the serial # with me tonight
Yair . . . productpedler . I find that almost incomprehensible . . . what do they suggest? Cheers.
Lol not me scrub, I've had them tell me that more than once! The G series are mechanical throttle aren't they? Do you have a fuel delivery problem, such as a lift pump or plugged suction (fuel algae) ? Pj
G engine is pretty simple. So are some of the guys I work with though. G engine is all mechanical. If it slows down, it is being told to by cable or losing fuel flow. 90 on back of the fuel transfer pump are notorious for getting plugged. That said, I have seen bases that get plugged as well. Lift pump should have 7-11 psi and have a good 1/4" stream of fuel at injector pump.
Sounds like fuel starvation, how about shut down linkage, have had problems with them sticking and not wanting to start. Fuel pressure would be great start like cat mec stated spec.
Let me give the entire history and maybe it will help. We had NO issues until 1500 hrs on machine. It was on a timber tract and left over the weekend. (running like it should when shut down) I came back to load on lowboy and the machine would not move. It ran perfectly but the electronic parking brake would not release. All other hydraulics and operation was as normal. The engine would idle up and hold but it just wouldn't move due to the parking brake. The local CAT guy came out and said that a rat had chewed the wiring in the belly pan. He fixed it and sent us on our way .($1500) Three days later , on a different job site the machine did the same thing again. The local CAT guy came back and said the identical thing happened again ....($1200) The machine ran ok for about two weeks then this problem arose. We pulled the belly pan off and cant see any naked wires or anything out of the ordinary.
Your problems might not be related. But engine rpm is mechanical, either low fuel supply or pressure, or rat moved into intake? Start at square one, never assume its the same thing. Will engine rev up and stay in neutral? Without trying to move?
Thanks guys, I have asked a few more questions of my operator. Here's the deal. The idle up and down on the machine is working as it should. High idle is not a problem. The electronic speed control is where the problem starts. When the system is cold, it runs as normal. At some point later (sometimes 2 minutes-sometimes 2 hrs) the speed will decrease and when it does, it slows down extremely quick. The operator says it will nearly throw you out of the seat. It will also at times pull hard to the right. The pulling is not the normal problem, but it has happened a couple of times. The operator says the machine is like it is stuck in low gear.
Cat D5G XL model#3046 SNMHK12710 Arrangement 2113012
If it was a loader I would tell you to calibrate It or have the comp re-flashed, not sure how these little critters operate tho Pj Edit; we have such a problem with the C machines and electrical storms that all of my loaders have the calibration procedure printed off and setting in the machine and my operators have gotten quite quick at it we have to re calibrate them every few weeks...... We aren't just talking about one machine either!
This sound like a calibration as well. Engine, pumps and drive motors all have to be in sync of it can give you some of the faults you have. I think you need an throttle calibration. You do have to have Cat ET to do it though.
Productpedler does this happen as you start going up a grade? Work good going down a grade? Later Bob
No certain time happens on flat ground or on slopes.
I have seen low power going up hill as well as hard starting facing up hill due to a bad lip seal on the front of the fuel pump shaft. To check park on level ground, push down blade all the way. Shut off and leave for a while. If there is trouble starting lower the front and see if it starts better. If seal is bad it will not start untill the front is lowered. Later Bob
Are you getting any fault codes or active faults when it acts up?
Did you figure out this issue. I have a d5g log doing same thing
Keith first check the voltage at the batteries and the Alternator. It should be 14.4V, if it's not then start there. If it's 14.4 on both then it could be a calibration issue or something else. The G series are very, very picky about voltage. We had an alternator going out that would stop the dozer dead in it's tracks no matter the speed like you put the parking brake on. First replaced the park break rocker switch - no luck. Finally checked the alternator and it was putting out less than 14.4, I forget the actual value. Changed the alt and tractor ran fine. Not saying that's your issue but a first place to look. Also had our D5G calibrated with ET twice over it's 17 years. Usually we can tell when it needs to be calibrated when the speed does not stay consistent going from forward to reverse. At the moment reverse is the correct speed on the dash but forward is slower. Voltage is fine so it needs to be plugged into a Cat laptop. OH Yeah the real mechanics will want a serial number to better help you.
Ok serial number is rkg01367 ended up having to rebuild motor on this thing because of blown head gasket. Back running now but still having the issue. Planning on calling cat and getting them out here to look at it and get it calibrated if nothing else