I HAVE A 1996 CAT 953C 2ZN
Had a local hydraulic shop pull the engine for rebuild which included removing the cab, disconnecting wire harnesses, sent the engine off for complete rebuild, sleeved, new injectors, turbo, exhaust manifold etc. Reinstalled and engine sounds great.
Now for the problem. Went to pick it up and at full RPM Loader moves forward very fast at first and then slowly decelerates to a stop after 50-60 ft, both forward and reverse. Changed 2 hydro filters under right side of cab with NAPA 1730 and 1759 filters. Ran it again, added more hydro fluid and noticed quite a bit of air in the sight glass, guessing do to the filter change. Ran it again, no significant difference.
Lowered the throttle rpm by a 200 RPM and comes out of it and acts similar to the way it did before the engine rebuild. Full throttle acts up again. Lower throttle seems better.
Disconnected all power to the machine hoping to reset any codes or computer related issues.
Called Cat dealer and the field tech has never heard of such a thing. Just signed up for this forum today after reading the below post from 2010 with a gentleman that had the exact same issue, but I dont see that he posted a resolution. I would like to know the fix if possible. Any help will be greatly appreciated.
Ran fine, pulled engine, disconnected wiring, sits for 30 days, reassembled and now there are problems. Only 1 voltage light appears at low RPM which was not present before the rebuild. Is this a grounding issue?
I didnt do the work but are these possible issues. Grounding issues with wiring, wiring issues, computer reset, Engine RPM too high since rebuild and tranny going into bypass mode do to high pressure or rpm? Below is the post I found from 2010. Any help will be greatly. Thanks
953C Problem posted by flametamer
Posting for a friend:
We have a 1999 Cat 953C track loader with an attitude.
The history is: The engine was just rebuilt, which entails cab-off. After rebuild, the head shop which did the heads botched the job and the cab and engine came out again.
The problem is:
Now...the engine runs sweet. It's all hydrostatic and ECM controlled. At full throttle it takes off and then slows to a crawl in 30 ft. Engine still at full rpm. Bring the trans into neutral and it will again take off and slow down slowly to a crawl.
Now, if you keep the rpm 200 below the recommended operating setting (full rpm)....it works just fine, but lacks the governor response of the full throttle setting.
Cat has put their computer on the ECM and downloaded the data. Also two occurrences of low voltage, which was the battery going dead after sitting a while, which they said are not important. One weak track sensor was found and replaced. No difference. It has been operated for hours with the ECM on wireless and the laptop recording all data. Nothing shows up as the errors occur.
At this point they have given up on it. Cat has a unique form of doublespeak which really means "We are stumped, but give us all your money and we'll try to figure something out." (So BP-ish)
Has anyone dealt with or heard of a similar problem in any Cat hydrostatic drive systems?
Had a local hydraulic shop pull the engine for rebuild which included removing the cab, disconnecting wire harnesses, sent the engine off for complete rebuild, sleeved, new injectors, turbo, exhaust manifold etc. Reinstalled and engine sounds great.
Now for the problem. Went to pick it up and at full RPM Loader moves forward very fast at first and then slowly decelerates to a stop after 50-60 ft, both forward and reverse. Changed 2 hydro filters under right side of cab with NAPA 1730 and 1759 filters. Ran it again, added more hydro fluid and noticed quite a bit of air in the sight glass, guessing do to the filter change. Ran it again, no significant difference.
Lowered the throttle rpm by a 200 RPM and comes out of it and acts similar to the way it did before the engine rebuild. Full throttle acts up again. Lower throttle seems better.
Disconnected all power to the machine hoping to reset any codes or computer related issues.
Called Cat dealer and the field tech has never heard of such a thing. Just signed up for this forum today after reading the below post from 2010 with a gentleman that had the exact same issue, but I dont see that he posted a resolution. I would like to know the fix if possible. Any help will be greatly appreciated.
Ran fine, pulled engine, disconnected wiring, sits for 30 days, reassembled and now there are problems. Only 1 voltage light appears at low RPM which was not present before the rebuild. Is this a grounding issue?
I didnt do the work but are these possible issues. Grounding issues with wiring, wiring issues, computer reset, Engine RPM too high since rebuild and tranny going into bypass mode do to high pressure or rpm? Below is the post I found from 2010. Any help will be greatly. Thanks
953C Problem posted by flametamer
Posting for a friend:
We have a 1999 Cat 953C track loader with an attitude.
The history is: The engine was just rebuilt, which entails cab-off. After rebuild, the head shop which did the heads botched the job and the cab and engine came out again.
The problem is:
Now...the engine runs sweet. It's all hydrostatic and ECM controlled. At full throttle it takes off and then slows to a crawl in 30 ft. Engine still at full rpm. Bring the trans into neutral and it will again take off and slow down slowly to a crawl.
Now, if you keep the rpm 200 below the recommended operating setting (full rpm)....it works just fine, but lacks the governor response of the full throttle setting.
Cat has put their computer on the ECM and downloaded the data. Also two occurrences of low voltage, which was the battery going dead after sitting a while, which they said are not important. One weak track sensor was found and replaced. No difference. It has been operated for hours with the ECM on wireless and the laptop recording all data. Nothing shows up as the errors occur.
At this point they have given up on it. Cat has a unique form of doublespeak which really means "We are stumped, but give us all your money and we'll try to figure something out." (So BP-ish)
Has anyone dealt with or heard of a similar problem in any Cat hydrostatic drive systems?