Cat 426B only reverse, no forward gears.

[OarngeOveralls]

We have a cat 1990 Caterpillar 426B Backhoe. About six months ago we could not drive it in the forward gears, it would only drive in reverse. We have since dropped the transmission and replaced all of the reverse and forward clutches and clutch basket as well as bearings and the races. We replaced both solenoids. We reinstalled the transmission and we still only have reverse working. When we do place the transmission selector into forward it tries to move slightly forward then stops. Any suggestions would be greatly appreciated.

 

[ahart]

Have you put gauges on transmission pump pressure and forward clutch pressure ports? Do you have a manual for testing and adjusting?

 

[OarngeOveralls]

We do have gauges. I have a manual, but I do not see anything for adjusting the pressure.

 

[OarngeOveralls]

We have the maintenance manual and parts manuals. We do not have the shop manual for testing and adjusting pressures.

 

[ahart]

Post serial number so I can be sure I’m attaching the correct information for your machine.

 

[Mobiltech]

I’m not sure what that year has for a forward neutral reverse shift control but I have seen the contacts in some get dirty and not send the power to the shift coils.

 

[OarngeOveralls]

6KL00283

 

[ahart]

Here’s a testing and adjusting guide for the powertrain.

 

[OarngeOveralls]

Thank you. I will let you know what we find.

 

[DaveBeaudry]

Thank you. I will let you know what we find.

Hey OarngeOveralls, did you find your problem. I have same machine with that issue. Call me if you can, 807-220-4802.