Would there be a need to bleed the system on our old 988a transmission after draining and refilling?
I would say that you certainly need to make sure the pump is primed before starting the motor. I guess you could ensure the pump is full by backfilling it via the transmission filter housing. TBH if all you have done is drain the oil the pump and lines should still be full. No harm in confirming though.
Thank you. This goes back to that transmission neutralizer we have spoke about on this machine a few times. Yesterday they pulled the spool out and it indeed was stuck. It had a little Gunk on it but nothing terrible. They cleaned everything up and reassembled it. In the process they had dropped a little plug into the transmission. They drained the transmission to get the plug out, which they achieved. No debris in the oil. And when they had it drained they ran a scope up in the transmission and down from the top. Everything looked good. The only issue that was found was the neutralizer valve was stuck. Reassemble the machine and put oil back in it. Still can't get it to move. So just grasping at straws and hoping maybe it needed to be primed or bled.
You should measure normal transmission pump pressure even if the neutralizer is depressed. All the neutralizer does is to dump direction clutch pressure. Pump and speed clutch pressure would not be affected. Have you had a pressure gauge on it yet.?
Yes. And it looks like is at 250. Which is low. Neutralizer valve is working fine now, we are now looking into the safety valve
Can anyone tell me if trans to-4 transmission oil can safely take the place of the trans 30 caterpillar used in the older transmissions? Or should I just put in 30 weight motor oil?
Michigan is just below where I was raised in Northern Ontario and gets very cold in the winter. You need to be looking for a 10 weight oil or less, cause 30 weight moves nothing at minus 20C and is to slow to get to necessary components. Been through this too many times, not even good if parked inside cause if it dies outside, which happens in cold weather, you will be making a huge tent to cover it with heat before getting it going again. Only my experience. Your Call. Simon C
10W30 TO-4 would be a potential option. I'm not sure that 10W alone would have a high enough ambient rating to cover summer temperatures, although it would certainly cover operation in very cold weather.
We had to go to 0W30 in Northern Ontario in 1996 as it was minus 40 for over a month. With 10 weight the oil would freeze in the steering cylinders if the machine was not moving for 25 minutes. And it does go to minus probably 30 where he is. We use to change the hydraulic and transmission oil back and forth every spring and fall. Had 2 Cat 966D&E that got this service every year. Simon C
Gotcha. In that case i agree that 0W30 TO-4 would probably be a better bet than the 10W30 I was thinking of.
At true minus 40C you can take a big pot of boiling water and throw it off a second story balcony,and a few flakes of snow will hit the ground. the rest disappears in the air. You have to see to believe. Look it up on You Tube. Kind of neat phenomenon. Minus 40 or colder does strange things. Simon C
I had that experience working in Siberia......... TBH I had not noticed the OP's location until you mentioned it. Shows I need to pay more attention.
Nige, your more on the ball than 99% of the people on this forum. Hard to slip one past you. Simon C