Cat 963c two speed not working moves slow

[Sbird]

Last two test with implement racked full forward or reverse rpm dropped little out range and implement rack forward the right reverse pressure was just 240 where all other pressures were above 300

 

[pittsburgh cat man]

I'm not seeing any thing too concerning with the pressures as a matter of fact seems to be doing pretty good for weak pumps! I was interested in seeing if brakes would hold under stall. It was making me wonder when it was going in circles. Did you try turning up min. speed till it just moves and back it off 1 click?

 

[Sbird]

Yes didn’t move at all under stall set perfectly still and yes sir I did try setting minimum speed again and still no change

 

[pittsburgh cat man]

lets try changing one of the reverse solenoids with the override solenoid careful though it might screw up reverse tracking

 

[Sbird]

lets try changing one of the reverse solenoids with the override solenoid careful though it might screw up reverse tracking

Did that the reverse ones are new and one forward one is new so I swapped with new one and also removed brake control solenoid it was grungy cleaned it up tested it and it acts kinda sticky like sometimes doesn’t open all way but most time as good reinstalled it and still no change in speed

 

[Sbird]

Failed mention also tried calibration again still fails at 17 for setting top speed

 

[pittsburgh cat man]

I'm going to have to thing about this for a while Every thing you check seems right even signal to motors is pretty close it's a couple pounds shy of what it should be but it should be at least be very close to min angle on motors The thing that bothers me is if it's a motor problem they would both have to have the same problem. This seems more of a control problem. because it effects both sides. Was the guy you bought it off of the first owner? Did he mention about it being slow? This is going to turn out to be something stupid like someone was trying to slow it down to save the track!

 

[Sbird]

I'm going to have to thing about this for a while Every thing you check seems right even signal to motors is pretty close it's a couple pounds shy of what it should be but it should be at least be very close to min angle on motors The thing that bothers me is if it's a motor problem they would both have to have the same problem. This seems more of a control problem. because it effects both sides. Was the guy you bought it off of the first owner? Did he mention about it being slow? This is going to turn out to be something stupid like someone was trying to slow it down to save the track!

Well I bought at auction and just now found out through cat who owned it before I can’t get in contact with him to see what he knows I’m guessing when cat told him needed two pumps he just sold this was after they told him new ecm and didn’t fix problem so guessing he just cut his losses ! I agree I think it’s something I’m just missing because it has a ton of power up to 2mph will show mountain of dirt and will spin tracks easy if you Barry bucket in ground so to me it’s hard imagine pumps are weak

 

[pittsburgh cat man]

This is going to sound dumb but down on the motors there are sensors to read signal pressure to motors check fittings between sensors and motor for being plugged

 

[Sbird]

This is going to sound dumb but down on the motors there are sensors to read signal pressure to motors check fittings between sensors and motor for being plugged

Ok took both lines off at motor coming from sensors for signal pressure and found nothing obstructing them then went in sub 26and 27 for signal pressure in 26 pressure was at 110 high idle park and raised to 1710 full forward and 1800 full reverse
In 27 it started at 105 at high idle park and raised to 1560 full forward and 1770 full reverse

 

[Sbird]

Really wondering if C mark might be right if at some point someone has been tampering with adjustments on motors ? Seems to me they are 100 percent not taking over when they need to and I’m just getting the 33 percent power

 

[pittsburgh cat man]

There is a way to set them look in stuff Nige sent

 

[Sbird]

There is a way to set them look in stuff Nige sent

Yes just been studying that exact thing thinking might try to do that procedure start to finish and see what results I get

 

[Sbird]

Back in post #116, you said pilot pressure at max fwd and rev was 200psi. This is about right. I have a feeling it may be just the motors that aren't destroking. I ask again, does it look like the motor adjustments have been tampered with?
Whatever the answer though, we still need to be getting a reading from the speed sensors to adjust things properly.
View attachment 336394

Hey Cmark I got speed readings figured out just crawled under and began adjusting sensors in from what book said was right went half turn at time and at 1 1/2 turns from bull gear I’ve now getting speed reading on both tracks

 

[Cmark]

Hey Cmark I got speed readings figured out just crawled under and began adjusting sensors in from what book said was right went half turn at time and at 1 1/2 turns from bull gear I’ve now getting speed reading on both tracks

That's good. Probably a bit close for comfort but should be OK for troubleshooting. You can reset them to 3 turns when you're finished.

 

[Cmark]

To adjust the motors on the machine, you will need some way to monitor track speed when you are working underneath it. Do you have access to ET?
You will also need ORFS blanking plugs for the two signal hoses.

 

[Sbird]

To adjust the motors on the machine, you will need some way to monitor track speed when you are working underneath it. Do you have access to ET?
You will also need ORFS blanking plugs for the two signal hoses.

View attachment 336602

Yes I have plugs but no access to ET

 

[Cmark]

You will need to figure something out. Maybe a helper in the cab videoing the display while on a face time call with you underneath??

 

[Sbird]

I will try that I’ve got buddy who can probably help me with that

 

[Cmark]

Do this one side at a time.

• Disconnect the signal hose at the motor. Plug the hose. Leave the fitting at the motor open.
• Put a good accurate pressure gauge on the forward signal pressure tap for the side you are adjusting.
• Run the engine at high idle and monitor signal pressure and track speed.
• Move the FNR control slowly forwards. Watch the track speed and stop at the exact moment the track speed stops increasing. At this point the pump is fully upstroked. Record the signal pressure and track speed. Return the FNR to neutral.
• Stop the engine and reconnect the signal hose.
• Back off the motor adjusting locknut and adjuster a few turns.
• Run the engine and move the FNR until you get the same signal pressure that you recorded earlier. Your track speed should also be the same as earlier.
• Start to slowly turn in the adjuster. Watch the track speed closely and stop the adjustment when the track speed JUST begins to increase. At this point, the motor is beginning to destroke to give you your upper range of speed. If you overshoot on the adjustment, back it out and start again. Adjust on the rise.

You may have to try a couple of times to get it right. If you get a dead band or a sudden speed increase part way through the FNR travel, try again.