450C reverse gear problem

[KSS Const.]

I bought a 1983 450C loader with 9300 Backhoe. Been using it for the last few months around my property without any issues. The last couple times I used it, it dogs out in reverse almost to the point of stalling. Forward travel works fine. Transmission fluid level is fine. This is happening even on level ground. I was thinking maybe a brake problem but no trouble moving forward. Any thoughts of where to look?

[DrLoch]

Sounds like the foward clutches may not be releasing which is odd. There is a rod in the trans that mechanically makes sure one is released before the other can engage.

[KSS Const.]

Thanks for the suggestion. If that's the problem would the forward clutches still be partially engaged in neutral? That is not happening as I can sit in neutral without any travel.

[DrLoch]

I can't answer that. Have you checked the clutch control unit? Among other things it has the shift valve that directs the flow of fluid to the clutch packs. Does it do this in (HLR) High and Low range? Only other thing that I can think of is that a seal went out on the clutch shaft allowing oit to pressurize a forward and reverse clutch packs together. I may be wrong about the mechanical rod... thought I had seen one but after looking in manual I'm not seeing it now... The clutch control/shift valve control where the fluid is being directed with respect to the clutch packs Look at 50 Group 20-1 in the manual, that is where it explains the workings of the clutch control and shift valves.

[Scottyb]

it might be a brake pad binding, I had this problem on my 350b. As yet I have not fixed it however I backed the adjuster of a bit and it works fine again. I would push up a pile of snow then I could not back away from it. I figured it out by watching the brake linkages when I was backing up and they would apply without stepping on the pedal.

[Dave Buchanan]

You could try pulling both steering clutches levers back . Put HLR in reverse, this will tell you if problem in transmission . If HLR unit works release one steering lever at a time .You will be able figure out what the problem is .