Hello all, I have just bought a Kubota M4500DT. I have browsed this forum and found some answers, thank you all. Special thanks to JohnDB who has helped me with manuals and diagrams. The engine was a nightmare to fire up. White smoke and running very rough until it eventually fired and once it was warm it started straight away. I read these are renowned for hard starting, ( this may help others) so I went through everything, figuring there is bad glow plugs for white smoke unburnt fuel, well they all tested individually for resistance okay, took two out and put them to the battery and they glowed nice and hot. I have a more modern Kubota excavator KX 161-3 and the glow shows on the key switch, wait a few seconds turn key and and fires. Well this is my first tractor and I have been turning the handle left for the glow but not looking for long because i thought the glow wire was an indicator which wasnt working and not part of the actual start circuit. (continued)
M4500DT 3 point linkage not working after oil change
- Thread starter Fishfarmer
- Start date
It tries to fire but takes so long to get running, so I read turn the knob for a minute or more. Finally got the wiring circuit diagram and here is to my embarrasment ( I am a last century electrician so I should know better) There is no power to the glow plugs at all. Dumb as, thinking there must be power to some plugs for it to fire. Turns out I have been firing it without any glow plugs with power to them at all. I ripped the dash out and and sure enough the wire was pulled out from the start switch to the glow wire. A quick glow now and bang she starts straight up. I dont think this tractor has ever been serviced I have never seen anything as negelected, with a bit of luck I may be able to save it. ( continued)
Which brings me to my questions if anyone can help? Oil was as black as, including transmission so I changed everything. Some metal filings on the hydraulic magnet, grease like grey graphite, I assume is metal on the magnet and also some 5 to 10mm shavings. I will post a picture of these because they worrry me a bit. There is about half a dozen thin and a bit springy like a piece of feeler guage. My main problem is the 3 point linkage was working fine and after I have done the oil change using STOU 15w/40 the 3 point linkage stopped working. Now I took the Oil filter out to clean and also the canister from the hydraulic pump to clean any shavings. To be able to get the canister off I took the hydraulic steering connections off the pump. I am pretty sure I replaced the filter properly and all the orings on the hydraulic connections on the pump. Hydraulic steering is working fine. I hope there are no stupid questions but I read where hydraulics dont need to be bled? I have put about just under 45 litres of tranny oil in and its halfway up the dipstick so although I am not to the top I wouldnt think its low on oil, any ideas anyone?
I don’t know what “STOU 15W40” is…. but that sounds like ENGINE oil…. not Hydraulic Oil such as most Kubotas use. (Kubota UDT in that vintage I beleive.)
Thanks GeoHorn. Its Gulf Western farmoil STOU 14W/40 recommended for use in everything apparently. I was sceptical about it especially in the engine actually, but I was going to run it through everything and then do another oil change with the rcommended oils. I cant see how a 14w/40 is recommended for the gears which take a SAE 80/90 but apparently it does.
FARMOIL STOU 15W-40 - Gulf Western Oil
FARMOIL is a STOU (Super Tractor Oil Universal) formulated to meet all the requirements of most modern tractor manufacturers calling for a STOU type oil. It provides protection against brake chatter and squawk.
www.gulfwestern.com.au
While it's not your model of tractor it seems others have had similar problem, if you look at these threads you might find a solution or 2 worth trying:
https://www.orangetractortalks.com/forums/threads/l345dt-hydraulic-problem.53168/#post-485248
Kubota M4050 hydraulic / lift arm problem
I have an 85 M4050 and the lift arms are stuck in the lowest position after being parked with lift all the way down. draft control does not appear to be engaged. Changed fluid and cleaned filter a few weeks back, all looked good. Fired right up and lift worked as it always has. Did some bush...
www.orangetractortalks.com
Good luck.
Your vintage Kubota is more like a Fiat tractor painted orange. My point is that the usual Kubota oil cautions are not so relevant.
From page 223 of WSM:
You need to rule out any air leaks on the suction side of the pump. I have shown typical locations on the parts illustration.
Rubber hose #14 and its clamps #15 + any splits in the metal tubing.
O rings and seals along the length.
An air leak will not necessarily show up as a hydraulic leak.
On rare occasions using a shop vac to pressure the transmission/reservoir can help a pump re-establish its prime.
Dave
From page 223 of WSM:
You need to rule out any air leaks on the suction side of the pump. I have shown typical locations on the parts illustration.
Rubber hose #14 and its clamps #15 + any splits in the metal tubing.
O rings and seals along the length.
An air leak will not necessarily show up as a hydraulic leak.
On rare occasions using a shop vac to pressure the transmission/reservoir can help a pump re-establish its prime.
Dave
Thanks Dave, I will go through these first because I have taken them all off. I thought because I did not refill the hydraulic filter canister that it could just have an airlock. But unlike the diesel fuel system bleeding does the hydraulic pump draw enough suction through the lines and filter canister to prime it?
I first thought to crack the line at part 20 to see if there is pressure but like you say it only takes a micro leak from an oring or that hose connection to draw air under high pressure. That whole hose idea part 40 is a bit bodgy for any idea of a tractor if you ask me.
I first thought to crack the line at part 20 to see if there is pressure but like you say it only takes a micro leak from an oring or that hose connection to draw air under high pressure. That whole hose idea part 40 is a bit bodgy for any idea of a tractor if you ask me.
Thanks John, hopefully some results or at least daignosis todayWhile it's not your model of tractor it seems others have had similar problem, if you look at these threads you might find a solution or 2 worth trying:
https://www.orangetractortalks.com/forums/threads/l345dt-hydraulic-problem.53168/#post-485248
https://www.orangetractortalks.com/forums/threads/kubota-b7300-hydraulics-issue.47565/#post-414810 (HST tractor but it describes a solution to getting hydraulic pressure)Kubota M4050 hydraulic / lift arm problem
I have an 85 M4050 and the lift arms are stuck in the lowest position after being parked with lift all the way down. draft control does not appear to be engaged. Changed fluid and cleaned filter a few weeks back, all looked good. Fired right up and lift worked as it always has. Did some bush...
Good luck.
I would think you just lost prime on the pump. Take the inlet pipe of the pump and dump some oil into the pump.
Good luck.
Problem solved thanks everyone. It was indeed the hydraulic pump needed priming. I dont know how there is a procedure for these, unless a new hydraulic pump draws enough vaccum to fill the filter reservoir. Or like Dave said they are vacuumed. Other wise they are impossible to fill because of the S-bend design and if you do try to fill the filter canister at the pump end it just goes back in to the sump. The canister is much higher than the transmission. The solution which worked for me( may help others) is I backed up to a very steep incline so the transmission was higher than the filter, I cracked the inlet at the pump, some oil came out and the 3 point hydraulic primed up and started to work.
Another problem I have on this old beast is the ground and standard PTO lever down by the seat will not go in while the tractor is running ( crunches) even with clutch. I can put it in the horizontal position while tractor is stopped, then start and the PTO works for the slasher fine. Control arm PTO clutch lever at the front engages okay.
But if I put the ground PTO in the up postion nothing engages at all, ground PTO not working. I guess this could be a serious issue with a clutch or something? Finally my clutch is a lttle bit noisy (whirry) when it is not engaged running in neutral. If I press the clutch in the sound goes away. The sound is a bit like a throw out bearing spinning when on an old model car is wearing out. I am told this could be serious also?
Anyone with advice or answers please? I can take the worst case scenario.
Another problem I have on this old beast is the ground and standard PTO lever down by the seat will not go in while the tractor is running ( crunches) even with clutch. I can put it in the horizontal position while tractor is stopped, then start and the PTO works for the slasher fine. Control arm PTO clutch lever at the front engages okay.
But if I put the ground PTO in the up postion nothing engages at all, ground PTO not working. I guess this could be a serious issue with a clutch or something? Finally my clutch is a lttle bit noisy (whirry) when it is not engaged running in neutral. If I press the clutch in the sound goes away. The sound is a bit like a throw out bearing spinning when on an old model car is wearing out. I am told this could be serious also?
Anyone with advice or answers please? I can take the worst case scenario.
A couple of questions not really related to the subject line, you may be better starting new threads on each. But here's a couple of starters:
1. Ground speed PTO: probably a silly question, but that's me...
how to you know that the ground speed PTO isn't working?2. Clutch: on mine, if the gearbox is in neutral, and the clutch is engaged, there is a discernable whirring noise, and it sounds to me like input shaft and gears spinning inside the gearbox. I think the gears are straight cut, not helical like nice quiet car transmissions. Push the clutch in and the noise is consistent with the gears slowing down and stopping.
This model doesn't happen to have a 2 stage clutch does it? Where you have to push it farther than normal to engage the PTO when running. If so, maybe out of adjustment?
Thanks Chanceywd, , the clutch seems to be working fine as far as gears go but I will look in to what your saying about whether its a two stage clutch. PTO lever crunches to put lever in to live PTO, the lever comes up and goes in to neutral freely and goes further in to ground PTO without clutch but there is nothing working in ground PTO so I assume it is not engaging at all. As said PYO lever engaes when tractor stopped and then the PTO clutch lever works fine. I have just found out it is two speed PTO with a lever I didn't know about at the back. Still learning. I will start a new thread when I know more. Cheers
Your point about the PTO clutch adjustment could be valid, I haven't come across an adjustment process for the PTO clutch. These tractors have a lever for the PTO clutch, they don't use a 2 stage clutch pedal.
I am having similar issue after oil change my 3PT wont lift , so if i understand correctly you had tried priming the pump with oil in the inlet side on level ground and it wont work ? i tried it today and still
with the lever control there is absolutely no movement , no sound , power steering works so i am assuming pump is still working,. If i understand correctly what you are suggesting is to when back tires are high up park the tractor , come down and crack the pump open with screws , start the tractor and try the lever again and it will prime the pump, after which you tighten the pump top on the right side ? Did i understand this correctly ? pls correct me if i am wrong on this. If there is anything else you would want me to check in terms of filter housing next to it pls do let me know i am very very new to the tractor world.
I have just done a small overhaul and got some upgrades on my 4500DT but the 3points still dont lift , the neighbor who worked on my tractor said there is no pressure in the high pressure line and when he opened the filter there was hardly any oil in it. But the power steering part still works, DO you think the pump is going bad or is this pump really hard to prime when it gets old , i will again try the backing up to hill method but any pointers and help is really appreciated in this.
Did the 3 point linkage work before you did the overhaul?
I know mine was definately working before I changed the transmisson oil so I realised that it would be an airlock. The oil just keeps going back in the transmission so the filter can not fill up. It looks like a weird setup if you ask me, the filter housing can't be filled up, it is sealed at the top and the oil just flows back in to the transmisson and leaves a massive airlock in the filter housing. Unless a new gear drive pump draws the oil through with vacuum the only other way would be to vacuum pump it through. That is if your having the same issue I had.
It is some time since I did this but I will try to help you if I can. Have you tried backing the tractor up to a steep incline like I said?
I have a very steep grade where i did this. You may have to put it in diff lock on all wheels and do it where the tractor is straight. Just make absolutely sure you are safe and not on a side angle or where it can slip to the side. I remember that the hydraulic pump or at least the top of the filter has the be lower than the transmisson. Just keep reversing steeper until it starts to work. Let me know how you go.
P.S. I did not see all your question. i need to check but I don't think you need to crack any of the nuts on the pump or filter. Once it gets high enough the air lock goes in to the transmission and it primes itself. The filter is on the inlet side from the transmission, so the air flows back up the inlet line. From memory, I just sat on the tractor while running and it started to work. If it doesn't then crack the nut at the inlet on the pump, oil should come out if the housing is full, try that.
I know mine was definately working before I changed the transmisson oil so I realised that it would be an airlock. The oil just keeps going back in the transmission so the filter can not fill up. It looks like a weird setup if you ask me, the filter housing can't be filled up, it is sealed at the top and the oil just flows back in to the transmisson and leaves a massive airlock in the filter housing. Unless a new gear drive pump draws the oil through with vacuum the only other way would be to vacuum pump it through. That is if your having the same issue I had.
It is some time since I did this but I will try to help you if I can. Have you tried backing the tractor up to a steep incline like I said?
I have a very steep grade where i did this. You may have to put it in diff lock on all wheels and do it where the tractor is straight. Just make absolutely sure you are safe and not on a side angle or where it can slip to the side. I remember that the hydraulic pump or at least the top of the filter has the be lower than the transmisson. Just keep reversing steeper until it starts to work. Let me know how you go.
P.S. I did not see all your question. i need to check but I don't think you need to crack any of the nuts on the pump or filter. Once it gets high enough the air lock goes in to the transmission and it primes itself. The filter is on the inlet side from the transmission, so the air flows back up the inlet line. From memory, I just sat on the tractor while running and it started to work. If it doesn't then crack the nut at the inlet on the pump, oil should come out if the housing is full, try that.
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Thanks @Fishfarmer This is the info i needed , yes the 3 PT worked before my oil change without any issues, after the new hydraulic oil replacement i have been trying to make it work for so long but it doesnt, and what you said about how the air gets trapped and oil just keeps going back to transmission makes sense now i have to put it in practical
. So i will back up the butt of the tractor such that my transmission is much much higher than the pump which is just my dip from the road to the gravel near my barn , then sit there in the "same position working the height level up and down" ? if this will prime itself i dont have to work further otherwise i open a nut on the inlet side and then the air comes out and then oil oozes out which will prime the pump, did i catch all the steps correctlyThanks a lot for your help on this
Yes that is correct. If your linkage worked then I would think it is an airlock. I would assume all the tractors would be the sameThanks @Fishfarmer This is the info i needed , yes the 3 PT worked before my oil change without any issues, after the new hydraulic oil replacement i have been trying to make it work for so long but it doesnt, and what you said about how the air gets trapped and oil just keeps going back to transmission makes sense now i have to put it in practical
Thanks a lot for your help on this
Make sure you are higher with the transmission. It needs to be pretty steep, but as soon as your high enough it should work. I tried putting oil back through the line with a curved hose. That was hopeless because I realised the oil was just flowing back in to the transmission and only a dribble would be left in the filter. New ones must self prime through the gear pump, I don't know. Or they fill it with a vacuum pump. I dont think there is anything on it in the manual. The outlet from the filter is on top of the pump, crack the three bolts if you need to for it to bleed. Good luck and let me know how it goes.