Can anyone tell me where the charge pressure test port is on a cat 931C for the transmission?
Be happy to check in SIS but as there are at least eight different prefixes for the serial numbers and who knows how many variation there might be in each of them a full serial number would save a lot of wasted time on my end! Just one example of what you can see on SIS that needs more information to get to the answers: NOTE: Procedures and pressures for machines 7HF and 8AF are given on Pages 4 through 9. See Pages 10 through 16 for machines 2BJ and 6RF. NOTE: For machines 5LG with direct drive transmissions, see 931C Track-Type Loader Power Train, Form SENR3820 for testing and adjusting procedures. NOTE: For Systems Operation and Troubleshooting, make reference to Systems Operation Testing and Adjusting, 931C Track-Type Loader Power Train, Form SENR3820. NOTE: For specifications with illustrations, make reference to Specifications, 931C Track-Type Loader Power Train, Form SENR3819. If the specifications given in Form SENR3819 are not the same as given in the Systems Operation and the Testing and Adjusting, look at the printing date on the back cover of each book. Use the Specifications given in the book with the latest date.
Ok. Thanks. Its a machines I was going to look at buying. Transmission suddenly stopped pulling. My first thought was charge pump died. I'll see if I can get the seller to give me the serial number.
6AJ0134 is the serial number.
Well sorry to say but SIS is only showing parts breakdowns for that S/N! Hope someone else may have the information on test port.
Normally you can pull the plug on top of the trans filter housing I think its a #6 o ring boss thread pull up floor board and filter is at the front of trans. Should be a 11/16 plug
Thanks for trying to look it up in SIS. Thanks for the info. How much pressure should these have? Obviously if its zero something has happened. The filter has been replaced and the fluid level/condition looked good.
I would guess 300-350 psi
Thanks for the info.
Got a chance to test this finally. Getting about 175 psi to 200 psi at full throttle. Seems a bit low based on Dave's guess.
Listed spec appears to be 300+/-15psi with engine at High Idle and oil at normal operating temperature.
Thanks for the info. Its raining here today. I'm going to put a second hydraulic gauge on it just to be sure. I guess the next question is there a possible internal leak or is it the pump itself? I would also figure a weak pressure relief valve could cause it to be low.
Maybe Dave can chime in here but in the "adjustments" column the pressure chart states "NONE - controlled by modulating relief valve".
You need to pull the magnetic strainer and see what is in it then let us know
Got a better gauge on it. I have 400 psi at high idle cold. When I shift it into gear, it drops to basically zero. I take it the strainer is under the small cover next to the drain plug? Drain all the fluid and pull the cover?
I don't think you have to drain it but if you got no pressure in gear you need to pull the top cover and check the P1 and p2 pressures one is the directional the other is range. but pull the strainer and see if you have anything on it
Will do on the screen. It is located under the cover plate next to the drain plug, correct? What kind of pressures are supposed to be at p1 and p2? Thanks for the help. I really appreciate it.
Is your machine transmission 3F/1R or 3F/3R..? T&A specs for P1 & P2 are slightly different depending on what type of transmission it has.
I'm sorry. I should have included that. Its a 3F/3R transmission.
OK, so based on that here are the test pressures. All tests are with power train oil at normal operating temperature and the torque converter stalled against the brakes with the transmission in either 3F or 3R. P1 - 375+/-15psi P2 - 55+/-8psi less than whatever you measure for P1.
Thanks for the specs. They both test good. It's been wet here since I got the loader home. It's dried out here some today. I got a chance to crawl under it and have a look. The transmission yoke is broken.