Hey guys Having a problem with my loader, bought it on an auction so dont know the history of the machine. I rebuilt the engine from top to bottom. New pistons, rings, bearings,liners, oil pump, water pump, injectors, precombustion chambers, pump reconditioned I've replaced everything !!!! Timing done as per book spec. So my problem is that it seems to be slow on revving up and has no power when pushing a load. Climbing on to the low bed It will climb the ramps on idle. I just dont know where to look anymore Please any suggestions welcome
Try posting a Serial Number as a start. Then people will know where to look for info related to the machine/engine and will be able to ask you informed questions and/or make intelliigent suggestions based on what your machine actually is. Without that it's a cr@p shoot.
Hi Nige I keep forgetting to get the serial number for the loader Today I took pressures and my P1 was 150psi supposed to be 390psi. My P2 was 100psi which is supposed to be 55psi +- less than P1 so guess that's ok. Torque convertor inlet P3 was at 60psi . I took the transmission cover off under the seat to get to P3 on the contol valve and noticed that its dumping alot oil out of an L shaped cut out in the top plate, if I give it half revs it throws the oil out of the control valve onto the floor . Is this normal ?
Really need a S/N o confirm the correct specs. I'll start from the end - P£ (TC Inlet) is fine @ 60psi. P2 is derived from P1 inside the transmission control valve, so with P1 @ 150psi then P2 at 100psi is in the ball park. I'd imagine that the relationship between P1 @ P2 is not necessarily guaranteed to be within 55 +/-5psi when P1 itself is almost 250psi below specification. P1 is way too low and that is what you should be addressing first. Do you have a test point on the transmission filter housing..? As an aside, where exactly in Zambia are you..?
Hi Nige yes I took the pump pressure from the transmission filter test point which reads the same as P1 @ 150 psi. P3 convertor inlet pressure I believe should be at 140psi and is @ 60 so would seem all my pressures are at 50% of what they should be. I will post the serial number to you today. I am in the capital city of Zambia .... Lusaka Thank you for your replies
Sorry I was thinking TC out pressure not inlet. Inlet should be 130+ with cold oil. I’ll see if I can dig out a schematic for the power train hydraulic system. A S/N would guarantee that it was the right one.
Seems there is only one anyway. Here is the System Operation plus Test & Adjust for the transmission. Have you checked the adjustment of the transmission control linkages.? I wonder if it's worth temporarily installing an extra shim behind the load piston just to see if the pressures increase - see the diagram and chart on Page 7. If an extra shim doesn't change the pressure maybe pull the transmission pump and have a look inside.
Hi Nige yes I disconnected both linkages and made sure that they were all clicking into the neutral indent. My concern is where oil is escaping from the L shaped cut out on the the control valve next to the convertor inlet pressure test point P3 . If I start her up and let her idle the oil gushes out about 2" above the control valve it seems like it's coming out of the ratio valve for the torque convertor but I cant be sure. I dont know if it is normal for the oil to flow like this or not . I took a video of the oil under cranking speed but have no idea how to upload it
Btw the files you uploaded seem to be the same as I have access to.
I also checked that transmission neutralise is not kicking in
Model is 950E ,serial number is 63R06073.
You need to use a PC as opposed to a smart phone. Click the link and you have the option to open it as an Adobe pdf file or to save it (depends which button you click - see below). forget that I'm using Firefox as a browser. They all work pretty much the same way. 2nd illustration is Microsoft Edge.
All transmission control valves **** oil, even at Idle speed. The usual pressure testing procedure involves a Special Tool that is a sheet of 6mm thick perspex manufactured to the same shape as the cover with holes in it for the gauge test lines to pass through it. Bolt the perspex cover in place to replace the steel one and do the testing. The "Field Tool" is usually a square of cardboard with holes punched in it. As you have already found oil goes everywhere even at Idle speed. Try installing a thin washer (say 3mm) in addition to the existing shims behind the load piston cover. According to the shim chart on Page 7 of the T&A a 1.58mm shim should increase the pressure by 15psi approx. So a 3mm washer should increase the pressure by somewhere aound 30psi. If it does not respond like that, I would have thought the next options would be to go looking at:- a) The inside of the control valve to make sure none of the relief/control valves are stuck. b) The inside of the transmission pump. Apropos of nothing, have you disassembled and inspected the transmission filter bypass valve that is located in the head of the filter housing.? It will not affect system pressure but you need to make sure that it is not bypassing (due to being stuck maybe) otherwise the oil going round the system will never get filtered. Remove plug #4 and pull out spool #3 to inspect it.
Ref my post #13. Sorry just read your post again - I initially read it as "files I have no access to". I didn't realize you had access to a Service Manual, most people posting on here don't.
Thanks again for your replies . I have since removed transmission filter and found light score Mark's but nothing serious. Removed torque converter relief valve and found it free but over shimmed ( guess someone b4 me had a go at pressures) removed magnetic suction filter found it to be dirty with very fine metal particles. I have sent the control valve to South Africa to have it looked at as no one does it here. exhausted on ideas of where to look next so hope that they will.find something wrong with the transmission control valve .
Should’ve tried additional shimming under the trans ctrl valve load piston before pulling the complete valve. If that didn’t raise P1, then 99% certain it’s the pump.
Hi Nige been quiet as I've been trying all sorts I have another control valve that I have fitted I am now getting pump.pressure at 390 psi at full rev, but torque converter inlet pressure is sitting at 90 psi at full revs 50 psi down. What's the chances of the convertor leaking ?
Please remember that the 140psi is a MAXIMUM pressure you should see, not a target value that must be achieved. Most loaders are specified the same way, with a maximum pressure of anywhere between 130-140psi. It was not unusual to see 120psi on a brand new machine when cold. You are testing the TC Inlet pressure cold I hope..? NOTE: The oil grade can also make a difference to the max pressure you see when cold. What oil are you using.? Do you have any information regarding the replacement transmission control valve you fitted.? In other words, how good is it..? I assume that it is a used one from somewhere. Did you remove the "additional" shims from the converter outlet relief valve and set it with the quantity of shims that are supposed to be in it according to the Parts Manual..? That would be the normal starting point for testing. If the answer to the quesiton above is yes, then I suggest you try what I suggested in Post #14 above and install a 3mm shim washer behind the load piston and see what it does to the pressures.
Hi Nige Previously I was getting 350psi which was 40psi lower than it should be . I did shim the load piston as suggested and now an getting the 390psi. I did remove the extra shims in the outlet valve so it's back to what it's supposed to be, the oils I'm using is a 15w40 engine oil. All pressures seem to be within spec except for convertor inlet pressure at full rev 90psi
Please take note of Niges post above. the inlet relief valve is to protect the convertor from excessive oil pressure during cold starts and heavy oil
Thanks Mark. At the risk of flogging a dead horse - 140psi is NOT a target that must be achieved , it is the maximum that you should see. It is to protect the torque converter when the oil is cold. That is why the table of pressures clearly states with COLD oil, when all the other measurements without exception are taken with the machine at normal operating temperature. Anything less than 140psi is acceptable. What is the converter outlet pressure with all the machine systems fully warmed up and the transmission stalled in 3rd speed forward.? Also you really shouldn't be using engine oil in the power train. It does not have the necessary friction modifiers for the transmission clutches. The correct oil for the power train in your climate conditions would be an SAE30 that meets the Cat TO-4 specification. How does the machine perform now..?
hi i get that 140 is not a target but surely 90psi is low for full rev ???? i have not tested whn hot as im thinking it would drop even lower when hot
It could be that the multi grade oil you are using is contributing. The oil will behave like a 15 when it is cold. The recommended 30 would probably give you a higher pressure converter inlet pressure when cold. And TBH the converter performance is far more dependent on outlet pressure than it is on inlet pressure. Again my questions. This is the important one. What is the converter outlet pressure.? How does the machine perform now.?
Hi Nige I pulled the converter and one of the rings has worn quite a deep groove where it runs, when I put the ring into the groove the ring doesnt even clip together even the little catches on the ring have worn away. Would you have specs for the rotor and starter sizes but any chance ?
Sorry I pulled the converter out before reading your previous post
What you are looking for is dimensional information. The system does not contain that type of data unfortunately, it is generally only found on factory engineering drawings and I don't have access to that. Try posting some photos. I assume for "starter" you mean stator - damned auto-correct......