46a23593 serial number 8h. I believe it’s a 1970 model. I bought the machine non running and got it going. There had been some water in the pan(gallon or so) from where the machine sat for 6 years or so with no oil in it. I cleaned out the sump through the access panel on the pan and cleaned the pickup screen assembly. It runs and throttles fine. Warmed up the pressure is 30psi at full throttle. Regular idle is 8 psi or so and low low idle is barely off the stop peg of the gauge. Gauge is plumbed into where factory gauge is. From what I’ve read on here, 30 is fine but the idle numbers seem low to me. Before I ran it, I pulled the plugs from rear end and torque converter housings and drained off a little oil. There was a little water in both, but I found pieces of a bronze bushing in the torque converter housing. Looked like it was maybe a little under an inch diameter bushing, but hard to tell from pieces. When I drive it back and forward, it shifts fine and stays in gear good. In first gear, it won’t pull through the brakes. The driveshaft stops turning in the stall and the engine loads up pretty decent. Is it normal to not be able to pull through the brakes in first or is it getting weak? Also what oil am I supposed to run in the transmission/ torque converter? Thanks for your input, Jim
Not many bronze bushings in there the shifter shafts on top of transmission have two on each one there is also two brass thrust washers on planetary but they are flat and riveted to carrier scavenger pump and transmission pump bad bushings but they are not bronze and yes it should pull thru brakes in first at full throttle you could try wiggling shafts on transmission if bearings are gone you’ll have a lot of movement
You really need a service manual. Search for Cat Publication reference REG01220. Here's one - https://shop.fraleytractor.com/Products/65270541/caterpillar-reg01220 At first blush 30psi seems awful low. What pressure do you measure warm with the torque converter stalled.? numbers I could find were 38-58psi at converter stall and 20psi minimum at low idle. Oil for the powertrain should be an SAE30 meeting Cat TO-4 specification.
Nige, are you talking about engine oil pressure or converter pressure? Where do I put a gauge for converter pressure?
Engine oil pressure but to measure it under load you have to stall the converter, usually in 3rd speed against the brakes. The procedure to measure torque converter outlet pressure will be in the service manual.
I've never heard of stalling the engine to check engine oil pressure. Never seen an oil pressure gauge on and H that had numbers. All were just colors. Just the same those readings I would consider pretty low. When you did the stall, did you push on both brake pedals or just one? I've found a high horse eight will drive through one side brake in first and just barely not with both pedals pressed. What are you intending to do with the machine?
The engine oil pressure numbers I quoted are measured at full load. The only way to get that AFAIK is on a dyno. In the absence of a dyno torque converter stall RPM is as close as you're going to get.
I also found these pieces in the screen on the bottom of torque converter housing. I can stall it with one brake. I’m debating on pulling the converter out, it doesn’t look too bad unless I’m missing something. I figured I’d pull the scavenge pump next and see if it’s in decent shape. I want this machine to be in good working order, I’m not planning on making a living with it but would like to use it and have it preform like it should
I would say there are question marks over both the engine and the converter
You won't need to load the engine if you have oil pressure problems. I've had two of them lock up when the oil pump drive shafts snapped the splines out of the drives. The engine just starts to slow down till is suddenly stops with a thump according to the operators. Yours is in the category of in the hands of lady luck. It could run just fine for the entire time you want to use it or it could lock up before it pushes a full blade of dirt. There are two converter pressures that can be checked, but the only one that matters is converter outlet. As I recall there is an eight inch pipe plug on the outlet valve on the back of the torque converter housing. I don't remember the spec but I've seen them run between 10 and 20 PSI when at operating temperature. The torque converter inlet pressure is a relief valve that prevents too much pressure in the converter when the oil is cold. I don't recall if the check port is in the transmission case on the transmission control valve or just outside the case on a pipe joint. The cloth looking stuff in the photo reminds me of some gasket materials but I don't recognize the steel plug. It reminds me of a dowel but all the one in Cats that I've worked on were solid through their entire length. Have you figured out if you have coolant leaking into the oil pan?