L4150 Repair Restore
- Thread starter CiscoRanger
- Start date
Unfortunately no. I did get it moving back and forth some with a little kroil, but it is not moving and engaging like it should. I read that the hydraulic shuttle shift bypass flow lubricates the clutch components, so I might be back to seeing what is going on with the 3-pt hyd pump.
Update: Ok, so found another missing part...
I've been wondering where these two connections go, but kind of ignoring the electrical for now. Turns out there's a vacuum sensor that goes on top of the hydraulic pump suction line (where the red arrow points). Since it isnt installed, the hyd pump is just sucking air.
Granted, I should have noticed a threaded hole on top of the suction line, but i didnt. And it doesnt show in the parts diagram for the suction line. Only shows in the electrical section.
So I took a gloved hand and put some clean oil on the finger and covered the hole, and almost immediately the engine torqued down and started working harder at idle. I think we are finally drawing hydraulic fluid, or at least trying to. Still no 3-pt lift. but we are closer.
The pump started getting very warm, quickly. I'm assuming thats typical, and heat from compression/pumping is normal.
I've been wondering where these two connections go, but kind of ignoring the electrical for now. Turns out there's a vacuum sensor that goes on top of the hydraulic pump suction line (where the red arrow points). Since it isnt installed, the hyd pump is just sucking air.
Granted, I should have noticed a threaded hole on top of the suction line, but i didnt. And it doesnt show in the parts diagram for the suction line. Only shows in the electrical section.
So I took a gloved hand and put some clean oil on the finger and covered the hole, and almost immediately the engine torqued down and started working harder at idle. I think we are finally drawing hydraulic fluid, or at least trying to. Still no 3-pt lift. but we are closer.
The pump started getting very warm, quickly. I'm assuming thats typical, and heat from compression/pumping is normal.
Restorations are definitely interesting and fun!
Your discoveries are fun to watch (having been thru many similar ones).
I think some of the best parts are when you find stuff like this.
Hmmm, better look for some sales on PB Blaster, Kroil or your favorite flavor of penetrants!
Keep up the good work.
TheOldHokie
Well-known member
Lifetime Member
Equipment
L3901/LA525, B7200DT/B1630, G2160/RCK60, G2460/RCK60
That is not typical - it was running dry which will kill it in pretty short order.Update: Ok, so found another missing part...
I've been wondering where these two connections go, but kind of ignoring the electrical for now. Turns out there's a vacuum sensor that goes on top of the hydraulic pump suction line (where the red arrow points). Since it isnt installed, the hyd pump is just sucking air.
View attachment 88396
Granted, I should have noticed a threaded hole on top of the suction line, but i didnt. And it doesnt show in the parts diagram for the suction line. Only shows in the electrical section.
So I took a gloved hand and put some clean oil on the finger and covered the hole, and almost immediately the engine torqued down and started working harder at idle. I think we are finally drawing hydraulic fluid, or at least trying to. Still no 3-pt lift. but we are closer.
The pump started getting very warm, quickly. I'm assuming thats typical, and heat from compression/pumping is normal.
Dan
You may have figured this out, but you have a tandem pump setup. The power steering has a separate section with a separate reservoir, and one section of the pump (looks like the rear section) serves only the steering. So your steering issue is/was not related to the shuttle. You might want to check out the quantity and quality of fluid in the reservoir.
Dan I believe you’re correct again. The more I thought about it yesterday the less it made sense that the pump would really draw the motor down, which it was. With the sensor missing it was definitely sucking only air and running dry. No telling how many times it’s been run like that before I got it. Since I plugged the hole with a bolt it is pulling some hydraulic fluid but not much. So at least not dry. I’ve only started it a few times And didnt run it long.
i dug out my hydraulic pressure test kit last night that I bought for the skid steer and fortunately had the correct adapter to test the shuttle valve. There was fluid but no where near correct pressure.
i did some forum reading last night on the 4150 and a theme emerged…these tractors were apparently known for the issue of the brake lining deteriorating and clogging up the hydraulic filter. Thats very interesting because if that filter is clogged, it would potentially cause the hyd motor to have to work very hard to pull small amounts of fluid through the filter. hence bogging the engine. And also would explain why I have no 3-pt.
I think next step is to replace the hyd filter and see if it changes the equation.
So far I’m into this tractor for about $350.
$60 fuel to pick it up
$80 for hyd lines
$20 for misc bolts
$100 in hyd fluid
$40 hyd filter
$50 manuals
Pretty sure I’m still money ahead even if I ended up taking it to scrap. So we’ll go a little further. Thanks as always.
Po, I didn’t realize that at first, and thought they were a common system. It wasn’t until I saw the separate reservoir an traced the lines that I realized they were independent. I guess the fact that the p/s started working as soon as I hooked up the missing hyd lines was pure coincidence and the P/s had finally bled itself. Too funny. Thanks Po.
Question about the hydraulics for these old loaders. When I remove the loader, do I have to loop the hyd connections on the tractor side? As in connect the hoses to each other? from a couple of videos the newer 4 line systems don’t, but I read something last night about looping them and I’m not sure. It isnt covered in the loader manual that I saw.
Yeah, it looks like there's a hydraulic block in the line from the pump to the 3PH (and relief valve). When a loader is installed, the fluid is diverted from that block, through the loader valve, which should have a relief and tank return line, back to the 3PH. If you remove the loader valve and plug those openings, you dead-head the pump, and starve the 3PH's supply. You must jumper those together when the loader's off (or replace the original block cover, which I assume you don't have).
So maybe that's the purpose for that missing vacuum switch on the pump suction. Is there an associated indicator light on the dash? Besides the brakes, you've got clutches contributing friction material.
I'm surprised noone who owns an L4150 has piped up. Seems like it'll make a capable utility tractor to me - 50 HP, hydraulic shuttle, independent PTO, loader, power steering, draft control.
Alright I owe you Po. First, yes, from what I read, the vacuum switch illuminates a light on the dash that says you are not picking up hyd fluid. If you have a dash connected, that is.
Second, when I removed the loader, this is how I left the tractor lines:
after your message, I connected them:
and now my 3PH is operational! Additionally the torqued down whine went away. So all I can figure is, by not giving a return path on the loader lines, the hyd pump was constantly fighting that pressure trying to send fluid to the loader with no path back. Likely the cause of the pump heating up as well.
I also got the 3PH let down valve operational again with an overnight shot of kroil and some gentle working back and forth with pliers. This is encouraging!
Its amazing the problems we cause ourselves through inexperience.
Thanks Po.
As a side note that hyd filter looks brand new, no dirt on it, so I will hold off on the filter swap for now.
That leaves 2 things:
1) Main gear shift. I was able to slowly get the side to side movement to get it out of the middle of the ”H” guide:
but once I get it out side to side it moves back and forth freely. Not good.
that probbly means either the pin 120 is broken or the lever itself 110. I guess I’m pulling a seat off to get to the main shift cover. getting it in gear seems To be th only way to test the PTO. And then the final thing will be the actual shuttle shift.
I just wonder with it sitting wherever it was for so long and if there were open holes to the internals, if any water got in/ rust formed internally/ critters/bugs/insects built any nests inside. Glad to see you made progress, but I definitely wouldn't scrap it. There are plenty of people out there trying to keep these older ones going, so you could probably sell it and make a little before you sink alot into it....
I only have the parts diagrams, and your posts, to go by. Apparently a single and dual dry clutch were available. Since you have the shuttle clutches, I'm assuming you have a single-stage dry clutch. It's main function would be to enable you to engage the PTO. The PTO, I think, is independent of the wheel transmission, so it should work regardless of the other (known
) problem if the dry clutch is working. BTW, don't be surprised if the clutch disk is 'frozen' to the flywheel or pressure plate after sitting so long. Study the power flow through the transmission section in the WSM, and see what the Op Man says also.At this point, it seems you have both hydraulic systems circulating properly, correct? Is the fluid in each reasonably clean looking? You wouldn't want to damage something running the tractor while troubleshooting.
You've made good progress. Let's temper that a little by remembering this is a pretty early model for this much sophistication by Kubota. You may still have to split the thing to repair the dry clutch, hydraulic clutches, shifters, brakes, etc. I'd do as much troubleshooting beforehand. If necessary, you wouldn't want to have to do it over!
Keep it coming!
I’m about to give this dirty girl a bath before I try and open any covers. Let me go through your post in greater detail after.I only have the parts diagrams, and your posts, to go by. Apparently a single and dual dry clutch were available. Since you have the shuttle clutches, I'm assuming you have a single-stage dry clutch. It's main function would be to enable you to engage the PTO. The PTO, I think, is independent of the wheel transmission, so it should work regardless of the other (known
At this point, it seems you have both hydraulic systems circulating properly, correct? Is the fluid in each reasonably clean looking? You wouldn't want to damage something running the tractor while troubleshooting.
You've made good progress. Let's temper that a little by remembering this is a pretty early model for this much sophistication by Kubota. You may still have to split the thing to repair the dry clutch, hydraulic clutches, shifters, brakes, etc. I'd do as much troubleshooting beforehand. If necessary, you wouldn't want to have to do it over!
Keep it coming!
But in summary, yes and no. Both hydraulic systems seem to be functioning, but normally might not be the case.
Pulling it out to wash it the power steering (hyd system 1) went back to steering hard right. It seems to have clear fluid at a good level. Will worry about that later.
3ph hyd pump (hyd system #2) raises the 3PH but that’s really all I can test at the moment. The hyd shuttle valve has a priorit flow block in front of it that may or may not be functioning. Readings at the shuttle valve test ports are poor.
While the PTO might be independent in the clutch, I am assuming I still have to be able to get it in gear (Main gear) before the PTO or the drive will work? Is that true, or is the PTO completely independent of the main gear neutral?
I think it's entirely independent, but can't tell for sure. You don't happen to have that manual in PDF?
Its not gonna let me upload it, its too large at over 100mb compressed.
Heres pictures of the pages of the transmission section... first half...
Heres pictures of the pages of the transmission section... first half...