CAT 950H giving jerks

[mymachine]

No its ino parking brakes, they were doing it with forward and reverse gear shifting .(F n R switch)

 

[Nige]

In that case definitely install the drive shafts and take another video. I'd like to see how much the transfer case output flange moves when shifting from F->R and vice versa.

Also has anyone had a look at the contents of the magnetic screen for the transmoission suction..? See the attachment for the location on the rear RHS of the transfer case. What type of oil are you using in the transmission as a matter of interest..?

 

[kshansen]

Yes! very important to pull that magnetic screen to see what if anything is on it! That should be a first step before going any further!

The following are several questions I might be asking if I was there in person or things I might try myself.

I did a quick look back in this thread and may have missed it but can you say if this is a new problem? Or is this a new machine to you and it has done this from the first time you touched it?

If this machine had been working fine without this noise how did it first appear?

Did it slowly get worse or was it working nice and smooth then out of nowhere it started making this jerk/noise?

Same operator and job or new guy who never ran a machine before?

Does it seem nice and smooth when driving along down the road and only time it makes the jerk/noise is when stopping and starting or changing directions?

How about if say you are driving in 1st gear and shift to 2nd then to 3rd? Does it shift smooth from one to the next?

While drive shafts were out did anyone try turning the yokes to the front and rear axles to see if they had about the same free play/back lash?

How about with wheels blocked and parking brake released, did anyone try working the output shaft back and forth to feel free play in transmission gears?

Not saying any one of these questions will give a positive answer to the problem but might help eliminate something or raise another question.

One more thing does anyone else think this machine sound like it is idling fast? Hard to tell listening to the videos. Does it have a tachometer? Just checked SIS and it should have one. So what RPM is it running at at low idle?

One more thing I looked in a trouble shooting chart and found reference to Jerky shifting:
Problem: Clutch engagement is sudden. (This symptom causes jerky shifting.)
Probable causes:
1. Modulating valves (5) , (6) , (7) , (8) , (9) , (10) need to be calibrated. ReferenceFor additional information about calibrating the modulating valves, refer to Testing and Adjusting, "Calibration and Programming".
ReferenceFor additional information about calibrating the modulating valves, refer to Testing and Adjusting, "Fill Time for the Transmission Clutch - Calibrate".

2. Modulating valves are unstable.

3. A speed sensor has malfunctioned.

 

[mymachine]

In that case definitely install the drive shafts and take another video. I'd like to see how much the transfer case output flange moves when shifting from F->R and vice versa.

Also has anyone had a look at the contents of the magnetic screen for the transmoission suction..? See the attachment for the location on the rear RHS of the transfer case. What type of oil are you using in the transmission as a matter of interest..?

Yes i had seen the magnetic screen last time had been to the site and dint find anything suspicious and i use CAT oil ...

 

[mymachine]

Yes! very important to pull that magnetic screen to see what if anything is on it! That should be a first step before going any further!

The following are several questions I might be asking if I was there in person or things I might try myself.

I did a quick look back in this thread and may have missed it but can you say if this is a new problem? Or is this a new machine to you and it has done this from the first time you touched it?

If this machine had been working fine without this noise how did it first appear?

Did it slowly get worse or was it working nice and smooth then out of nowhere it started making this jerk/noise?

Same operator and job or new guy who never ran a machine before?

Does it seem nice and smooth when driving along down the road and only time it makes the jerk/noise is when stopping and starting or changing directions?

How about if say you are driving in 1st gear and shift to 2nd then to 3rd? Does it shift smooth from one to the next?

While drive shafts were out did anyone try turning the yokes to the front and rear axles to see if they had about the same free play/back lash?

How about with wheels blocked and parking brake released, did anyone try working the output shaft back and forth to feel free play in transmission gears?

Not saying any one of these questions will give a positive answer to the problem but might help eliminate something or raise another question.

One more thing does anyone else think this machine sound like it is idling fast? Hard to tell listening to the videos. Does it have a tachometer? Just checked SIS and it should have one. So what RPM is it running at at low idle?

One more thing I looked in a trouble shooting chart and found reference to Jerky shifting:
Problem: Clutch engagement is sudden. (This symptom causes jerky shifting.)
Probable causes:
1. Modulating valves (5) , (6) , (7) , (8) , (9) , (10) need to be calibrated. ReferenceFor additional information about calibrating the modulating valves, refer to Testing and Adjusting, "Calibration and Programming".
ReferenceFor additional information about calibrating the modulating valves, refer to Testing and Adjusting, "Fill Time for the Transmission Clutch - Calibrate".

2. Modulating valves are unstable.

3. A speed sensor has malfunctioned.

1. Yes it started and problem gradually increased,
2. No new guy all are experienced operators.
3. Yes smooth when driving along the road the noise come only when the gear gets shifted or when machine takes off after brake is released.
4. Regarding idle RPM dont know exactly, i ll be going to the site 2moro and will check by the way what should be the idle RPM?
5. Clutch calibration was done by the cat service person and completed without any error.

Thank you very much for your support..

 

[Nige]

I use CAT oil ...

Could you be a bit more specific about the type of oil you are using please.

Also, can you find out if the SERV CODE icon is lit in the Monitor Panel. This panel is located in the upper RH switch panel. See below - Ref #36



Here's a thought from left field........... Has someone switched off the transmission neutralizer..?

 

[kshansen]

Here's a thought from left field........... Has someone switched off the transmission neutralizer..?

Another good idea, one which is someone familiar with the machine might spot in the first few seconds!

 

[Nige]

Another good idea, one which is someone familiar with the machine might spot in the first few seconds!

We have three of them, and it's something that the numptys who get employed to run them appear to be able to do with monotonous regularity..........

 

[mymachine]

We tried both, neutraliser active and neutraliser not active. Same condition.

 

[mymachine]

Could you be a bit more specific about the type of oil you are using please.

Also, can you find out if the SERV CODE icon is lit in the Monitor Panel. This panel is located in the upper RH switch panel. See below - Ref #36

View attachment 196018

Here's a thought from left field........... Has someone switched off the transmission neutralizer..?

SAE 30 c4

 

[Nige]

I'm not familiar with that oil. Do you mean TO-4..?

Back to my suggestion earlier of reconnecting all the drive shafts and re-shooting the video.

 

[kshansen]

5. Clutch calibration was done by the cat service person and completed without any error.

So was this calibration done in an attempt to solve the problem? Or was it done for some other reason.
Did this "cat service person" do anything else like checking something or adjusting or replacing something? Or have any other thoughts?

Agree with Nige on reassemble and re-do the video and show us the RPMs it is running at while doing this jerky stuff.

 

[mymachine]

Clutch fill calibration was done to solve this problem by cat service person...
And nothing else is done...