Serial number is 931C 2BJ00147. I'm hoping someone with SIS could post a parts diagram to show how the plug with a spring, ball and shaft go together on the end of the pump. My friend took it out to fit the starter and we want to make sure it went back together the right way. The other issue is we can't seem to get the pump to prime. Injected about half a liter of oil in through case drain but can't get pressure. We have a stabilizer for the backhoe moving up very slowly but is about all we can get. There's was no unusual noises from the pump. I've read piston pumps can be a pain to prime. Is taking the case drain line off and putting a hose in a bucket the best way to tell if the pump is damaged? Is there an easy way to prime the pump?
I’m not sure what you’re talking about
Or this
I have one of these pumps off a machine i parted a few months ago. If your buddy needs it he can have it for the cost of shipping. It worked fine then.
EDIT: He said that is it. I found it on AV Spares once but can't find it again. What is it called? I think it might be a 4T 0384 pump but the pic. I found on AV Spares but doesn't show the threaded rod sticking out the bottom. Maybe there is a separate part number for the back section of the pump that would show it better? I asked if he could send me a pic. of the pump. It's vertical on the back of the pump. It's like another section bolted to the pump that has the adjuster. There is a small plug on top that looks the same and a threaded rod sticking out the bottom with a jam nut. There is no cover over the threaded rod. I don't see a ball on top of the spring though. There is also some kind of rod that goes in from the bottom with the spring and ball. He thinks he put it back together the same way but maybe the rod went it backwards? Best I can figure out is it is a compensator and adjusts the swash plate angle as well as the pressure. I read that it's very common to have to re-adjust after it has been taken out. It may have the pump in destroke and it can't decide if it should make pressure or flow. That why the action is very slow and jerky.
That's very generous of you. I don't think we can condemn the pump yet. I think we should back off compensator to see if the pump starts working and then re-adjust it to the correct pressure.
He got the pump working. He double checked the compensator was put back in properly. He took the cap off and there was no oil. Then he took the the spring and ball assembly out to check it was installed correctly and there also was no oil running out. He took it out a second time and all of a sudden oil ran out. Figure it must have just been a big air pocket not letting oil go anywhere. He's relieved the pump is working. I was told that piston pump is very expensive.
always fill the case drain or pull and make sure oil is there
We did use a big syringe to force oil in through the case drain (after not working) and the inlet was flooded too. Still wouldn't work but taking the compensator out a 2nd time the air finally came out. Hopefully no pump damage.