I have a 955L that barely moves under its own power (85J11104). It sat unused for ~10 years, and I understand that it was originally parked because of the issue I'm trying to diagnose. It isn't near where I spend most of my time, so I will only be with it on occasional weekends. I have a plan, but have not had time to work through it all, so in the mean time I'm looking for thoughts on what I might be missing. The machine is parked pointed down a slight slope, and will move under its own power downhill. To back up the slope it won't move, it just takes the tension out of the tracks in the other direction. If you press either of the steering pedals, the machine starts to turn slightly, and then stops entirely. Transmission shift linkage for speed is good. For direction, the rod ends are sloppy and need replaced. I have disconnected that linkage and used a bar to change direction, but I can't confirm I'm solidly getting it fully engaged in reverse/forward doing that. Next time I'm back with the machine I'm going to replace those rod ends and get the shift linkage working properly. Transmission pressures, I think look good, with a question about the inlet to the torque converter. About 360psi for the speed clutch and 310psi for the direction clutch at full throttle. I can't remember the number at idle, but it wasn't a lot less. Inlet to the torque converter is at 80psi max at full throttle. 0 at idle. When I shift, in every gear, the pressure drops and then within 1-2 seconds goes back to where it is supposed to. I didn't have the adapter to check the steering clutch pressure, but will get that for next time I go back. Fluids are good, strainers and filters are clean. I adjusted the brake pedal linkage and brake bands. The linkage was very close to correct already, but the bolts were loose on the covers for the brake band adjusters. The brake band adjusters had also been backed off significantly. I have not finished adjusting the steering clutches. I think this may be where my problem is. The linkage clearly has not been touched, and the covers on top of the steering clutch case had not recently been off. When I turn the levers on the steering clutch booster towards the rear of the machine so the rollers make contact with the valves in the steering clutch booster, the linkage is over an inch too short to connect, as it was set. I'm not sure I even have enough adjustment in the linkage to set it properly. I may be mistaken, but given this, I don't believe my steering clutches were disengaging when I tried to turn, and as a result the brake on one side was stopping the whole machine. However, I'm not sure why this would make the machine weak when trying to go straight forward or reverse, unless it indicates a bigger problem with the steering clutches. The other possibility seems to me to be the torque converter. I have not checked the pressure at the outlet from the torque converter. Does anyone know if that is 1/8" npt as well, or do I need a different adapter to put my gauge on it? It seemed to not be easy to get to. Next time I'm with the machine I'll spend time fixing the shift linkage, adjusting the steering clutches, and checking pressures on the steering clutches and torque converter. Any thoughts on anything else I should look at are appreciated. Tim
sounds like the torque convertor have you pulled the magnetic strainer to see if you have aluminum in it
Thank you. I have not pulled the strainer. I will do that. The reason I didn’t is because it has new fluid in the transmission, and the guy I got it from said the trans filter and strainer were clean when he changed it. I figured even if there was metal in the strainer it had been cleaned out, but I have probably run it 10-15 min, so if there was metal in it, there probably will be still/again.
I finally got around to pulling out the torque converter last weekend, and just tore it down today. No visible damage to any of the big parts other than some wear on the carrier, but the fit between the carrier assembly and the impeller, stator and hub is sloppy. The book says I should have to use a press to separate them, but they just came apart by hand after I removed the snap rings. The impeller rocks pretty significantly on the carrier. Is this a common occurrence, and is rebuilding this with new bushings/bearings, so everything is tight, likely to fix my problem? Thanks
if everything is sloppy you need to replace all the aluminum
Thank you, very helpful.
Two more questions: Stator 1T-1351 for mine doesn't seem to be available either from Cat or aftermarket. It looks like machines up through ~85J10157 used the same 1T-1255 torque converter, but with a different stator 1T-0743 and turbine 1T-0723 (vs. turbine 1T-1480 in mine). The rest of the parts mostly appear to be the same. Any reason I can't backdate mine with new 1T-0743 and 1T-0723 parts? Because this is a farm machine that sees very little use, and there is a massive difference in cost between Cat and aftermarket parts, I will use aftermarket parts. Are there any brands that are good quality that I should look for, or any brands I should definitely stay away from as far as aftermarket parts for the torque converter? Thanks, Tim
There is no information at all regarding why the earlier 1T0743/1T0723 stator/turbine Part Numbers were replaced by 1T1351/1T1480. For the newer Part Numbers have you tried AvSpare or Offroad Equiupment.?
Thanks very much Nige. I have tried AvSpare, Offroad Equipment, AMT, Heavy Duty Pros and a bunch of others unsuccessfully for the new part numbers. I'm going to go ahead and order the earlier parts and see if I can make them work.
The company name escapes me, but the new steering pump I got for my 85J from the aftermarket manufacturer in Italy has been problem free. Knock on wood!
I just went through an old 1965 D4D 78A serial from one end to the other inside and out. You would be surprised how much old stuff can be purchased new on Walmart.com Always check Cat. Some stuff will blow your mind how expensive, but I recently built the entire fuel system on that D4. And Cat parts were half the price of aftermarket. Before and after pics. Good luck!