450C Clutch pressures

[rufustoad]

Hi all,

I am hoping to get a bit of information on my early 70's 450C crawler. A few years ago, I decided to replace all the clutches in the dozer and after I did the tractor pushed fairly decent but late last year (sat all winter) and now I noticed the high-range was slipping. I checked my pressure today and around 2000ish RPM I can get aprox 180psi but idle I only see 80-100psi which might be acceptable just not sure. When I shift into low or rev my pressure drops considerably from 180 to 80 and high drops to 70psi. I also feel like I have bubbling in the area of where you actually check the pressure like in the bung area. No matter how much I adjust the linkages I get no rise in the pressure. Is there any way to check the accumulator/valve body or the shift linkage internally?? Is there any kind of leak that could have sprung in that housing that would cause this??
I need to specify that even with this low of pressure I can drive from LOW to REV pretty snappy an I feel no slippage either but nothing in High Range.

Any thoughts would be greatly appreciated.

[LeonardL]

It sounds like you need to do the adjustments for the HLR. I've seen this issue before and it ended up being the adjustments. There isn't anyway to see the internals without taking the machine apart.

There are a couple of places for your machine to leak internally but unfortunately they're all deep inside. Try your adjustments first and see what you have.

[Bobby H.]

Went through the same problems and did the complete clutch and hlr adjustments and Check the fluid in trans NOT running. Follow the manual step for step. Worked for me after the third time because I did not follow step for step

[rufustoad]

Thanks for your input, guys. I greatly appreciate it.
Anyone of you have a guide for these adjustments? I have the JD Tech manual, but it seems like it's all over the board and I get confused what goes first and then what is after that and there isn't IMO much for diagnostics in it

[Jim B]

JD publication TM1102 is the only Technical (service) manual for the 450C the JD Construction and Forestry bookstore shows.