machine and when i get the machine warmed..lever..pedel..slowing down…

Question

i have a 963c track loader with 8300hrs on the machine and when i get the
machine warmed up and have the hydrostat lever pullered all the way back going
across the yard not pushing on either foot pedel it will go along and start
slowing down on its own and just curious as to what the problem could be

catmastertech · Accepted Answer

I would like to help you with this problem. I don't work on many of these units
as they are not popular in my area (too muddy).

Please send me your serial number so I can find the correct information.

Finding the solution to a problem can be made easier if a few basic rules are
followed:

The performance of the system decreases very fast if the level and viscosity of
the oil in the transmission is not in accordance with specifications.

If the oil level is too low, the unit can malfunction completely.

Oil that is too viscous can cause the filter bypass valve to open. When the
filter bypass valve opens, oil is sent back to the sump. This causes a loss in
machine speed and performance.

Note: There is a filter bypass valve on the inlet side of the filter. The valve
opens whenever the pressure difference across the oil filter reaches 345 kPa (50
psi).

Oil that flows through the filter bypass valve is not sent through the
transmission.

There is a direct relationship between engine speed and the performance of the
hydrostatic transmission.

The engine speed must reach HIGH IDLE when the governor control lever is placed
into the HIGH IDLE detent position. The performance of the hydrostatic
transmission will be affected if the switch for the governor lever position is
not activated. This condition will also interfere with troubleshooting.

It is possible for the engine to run at a speed lower than HIGH IDLE, even
though the governor control lever is in HIGH IDLE.

The low speed could be caused by a linkage problem, quality of the fuel,
condition of the fuel filters, and/or air in the fuel system.

Complaints of low power in the hydrostatic transmission can many times be traced
to engine problems.

Other systems on the machine can cause a decrease in the performance of the
drive system.

Incorrect track adjustment can cause the machine to move slowly.

Holding an attachment in the engaged position can cause the machine to run
slowly. This occurs if the relief valve is already open.

A visual inspection is the first step of troubleshooting. Inspections should be
made with the engine OFF and the control levers in PARK or HOLD. Also, lower the
implements to the ground.

Check the level of the oil in the hydraulic tank.

Check beneath the steering pedals on the floor of the operator's compartment for
buildup of mud or trash which might limit pedal travel.

Check the track adjustment on the right side of the machine. The track should
visually sag between the top carrier roller and the idler.

Inspect all lines and connections for damage and leaks.

Note: Air or dirt in the system can be as much of a problem as a lack of oil.

Check the track adjustment on the left side of the machine. The track should
visually sag between the top carrier roller and the idler.

Inspect all wiring harnesses for damage or disconnection.

Check the dash for warning lights and note if the word SERV CODE stays on after
starting.

Do you know if it has been calibrated recently?

Ok, thanks for the update. Please post your serial number, it is a big help to
me when searching for information about problems.

Changing the filter is a great idea. Save the old filter and drain it. Cut it
open and lay out the media to inspect it for metal and other debris. Scrap
anything you find and pass a magnet over it, iron will stick to the magnet.
Brass and aluminum will stay on the media.

Be sure to check the pedals to see if they fully return, the smallest amount of
sticking can cause trouble.

Double check the display, make sure the hourmeter is not displaying "SERV CODE"
after start up.

Here are some items to be aware of when checking this machine.

The power train/hydrostatic transmission and the hydraulic system on this
machine use the hydraulic tank as a common sump.

When the oil in the power train/hydrostatic transmission and hydraulic system
gets hot, it causes the air to expand and build up pressure in the hydraulic
tank.

Pressure can remain in the hydraulic tank after the engine and pumps are
stopped.

Personal injury can occur if pressure is not released before any service is
performed on the power train/hydrostatic transmission or the hydraulic system.

To prevent possible injury, remove the cap from the oil filler tube before any
fitting, hose, or component in the power train/hydrostatic transmission or
hydraulic system is loosened, tightened, removed, and/or adjusted.

The cap must be replaced when the tests and/or the adjustments are completed.

The bucket and the other attachments must always be flat on the ground before
service is performed.

When it is necessary for an attachment to be raised while tests and/or
adjustments are being performed, be sure the correct supports are in place. In
the case of the bucket, it must be in the full DUMP position.

Move the machine to a location away from the travel of other machines.

Wear the seat belt, and be sure that other personnel are not near the machine
when the engine is running and tests or adjustments are being performed.

catmastertech · Answer