It does not have a loader. It only had a mid-mount mower when I bought it and I did remove the mower.
B7100 Overhauled now trying to seize up
- Thread starter sanddog
- Start date
I am pretty sure the valves are good, as I just set them. I am not sure the difference in temp at the measurement points mean a lot??? It could just be due to "center" reading being in the center of mass???
It really seems to stop fairly quickly, not like compression slow fading and if you try to immediately restart, the starter has a hard time turning over. If you wait just a short time 20 - 30 seconds, it spins right up without any obvious drag.
Does anyone have any experience with the thee-point lift feeling like it is engaging a gear set when moving to "up" position? My other Kubota is 400+ miles away right now, so I cannot compare between the two, but I don't every recall feeling another quite like this. It sounds just like quick gear shift and when first moving into lift position and I have no weight on the arms. If arms are fully up and then try to move to up position, you cannot due to what sounds like gears grinding.
I am thinking this could be related to the possible deadhead???
I am thinking this could be related to the possible deadhead???
North Idaho Wolfman
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I have not checked the feedback rod, but take a look to see if there looks to be a possible issue related to it. Could this result in the type of feedback I am getting that sounds like gears try to mesh when raising the lift arms???
The sound is the pressure relief valve opening. If you continue to move the move the lever to the up position when the 3-point is fully up this will happen. The control rod when set correct will prevent this. Jeff
Lil Foot
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1979 B7100DT Gear, Nissan Hanix N150-2 Excavator
How about the positioning of the directional control valve under the front of the seat? If it's wrong it can deadhead the pump.
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The "lever" shown in the diagram is apparently missing on my tractor. There is a stem with a pin through it that is turned cross-wise to the orientation of the fitting or the lever shown in the diagram?? Looks like the stem should be turned to the right; will check.
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Well, the mystery continues.
After looking at the repair manual numerous times to determine how to check the hydraulic relief pressure, I finally decided the poor picture is showing the pressure gauge attached at the banjo fitting where the high pressure line connects beneath the seat coming from the pump mounted on the engine. The manual calls for a special adapter and that makes sense you would need something special to measure pressure at that location. I followed the high pressure line back to the pump and found my tractor has an apparent accessory block in line. There is a 1/4 plug that I was able to remove and install the gauge at that location (see picture).
I started the tractor and let it run at a fast idle and watched the gauge. The manual says to let it warm up a little and then move 3-point lever to up position. It says the pressure should be 1570 - 1710 psi. There was 0 pressure before moving lever and with lever moved to up position, I saw a short bump in pressure of maybe a few 100 psi and then back to essential 0 as the arm lifted. I have the control rod loose. when the arms got to the top, the pressure jumped to over 1500 very briefly and the lever was returned to the neutral position by the control arm. If I try to move the level back to the up position with the arms already up, the pressure jumps up but there is just a sound like gears try to mesh but you cannot get anything else to happen. As someone said before, I am probably hearing the pressure relief valve. It all happens so fast, that I don't really see a way to really measure the pressure. Am I missing something here??? Should I be able to hold pressure on the lift lever to get a reading on the pressure gauge for more than a split second??? With the sound of gears grinding or something similar, I am not comfortable applying more pressure to the control arm.
Also, in the past the motor would run right at 2 minutes before sounding like it was coming under load and dying. Today, the engine ran for 5 minutes before it died. The ambient temps are lower today with rain in our area but I checked the motor and it is actually hotter than where it died before. Makes sense it would get hotter running for longer. The only other factor that I could possiblly determine is that I was probably running the motor a little slower to try and observe the hydraulic pressure.
With the tractor in "neutral" (HST), I did notice that the motor came under a slight load when I push the "go" peddle into the forward position. It did not seem to make any difference when moving to reverse, but a definite slight slow down when moving to and holding the forward position. The tractor will go forward and backup without any apparent problems.
I am not certain what is allowing it to run longer today, but did it every time and was certainly getting to higher temps than observed before when it would only run about 2 minutes.?????
After looking at the repair manual numerous times to determine how to check the hydraulic relief pressure, I finally decided the poor picture is showing the pressure gauge attached at the banjo fitting where the high pressure line connects beneath the seat coming from the pump mounted on the engine. The manual calls for a special adapter and that makes sense you would need something special to measure pressure at that location. I followed the high pressure line back to the pump and found my tractor has an apparent accessory block in line. There is a 1/4 plug that I was able to remove and install the gauge at that location (see picture).
I started the tractor and let it run at a fast idle and watched the gauge. The manual says to let it warm up a little and then move 3-point lever to up position. It says the pressure should be 1570 - 1710 psi. There was 0 pressure before moving lever and with lever moved to up position, I saw a short bump in pressure of maybe a few 100 psi and then back to essential 0 as the arm lifted. I have the control rod loose. when the arms got to the top, the pressure jumped to over 1500 very briefly and the lever was returned to the neutral position by the control arm. If I try to move the level back to the up position with the arms already up, the pressure jumps up but there is just a sound like gears try to mesh but you cannot get anything else to happen. As someone said before, I am probably hearing the pressure relief valve. It all happens so fast, that I don't really see a way to really measure the pressure. Am I missing something here??? Should I be able to hold pressure on the lift lever to get a reading on the pressure gauge for more than a split second??? With the sound of gears grinding or something similar, I am not comfortable applying more pressure to the control arm.
Also, in the past the motor would run right at 2 minutes before sounding like it was coming under load and dying. Today, the engine ran for 5 minutes before it died. The ambient temps are lower today with rain in our area but I checked the motor and it is actually hotter than where it died before. Makes sense it would get hotter running for longer. The only other factor that I could possiblly determine is that I was probably running the motor a little slower to try and observe the hydraulic pressure.
With the tractor in "neutral" (HST), I did notice that the motor came under a slight load when I push the "go" peddle into the forward position. It did not seem to make any difference when moving to reverse, but a definite slight slow down when moving to and holding the forward position. The tractor will go forward and backup without any apparent problems.
I am not certain what is allowing it to run longer today, but did it every time and was certainly getting to higher temps than observed before when it would only run about 2 minutes.?????
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![20160821_105339[1].jpg](/forums/data/attachments/21/21128-46d3406a458d24112685dfb7a5c79580.jpg)
UPDATE:
I have continued to try to get this tractor running without any problems. Before, it would idle for about 5 minutes before it bogged down and died or run about 2 minutes at higher speed before doing the same. I convinced myself it was not the motor and checked the 3-point lift to see if it was causing a "deadhead" and bogging down the motor. I found no problems with back pressure on the 3-point lift. I then thought maybe the HST transmission.
I tried driving the tractor and initially it continued to do the same thing - run a short time and bog down. If I waited about 30 seconds, it would fire up no problem. After trying this a few times, one day it suddenly just kept going as long as I kept it at idle. I drove around the yard and then let it sit at idle and it ran for 30 minutes before I turned it off. I have continued this and now I can run it a little above idle for extended periods, going forward, reverse, whatever, does not seem to matter. If I speed up the motor, then I get maybe 30 seconds before it bogs down and dies.
I assume the problem is in the transmission; somehow restricting flow at higher engine speeds. I have cleaned screens on both sides of transmission, with very little in the screens and changed out hydro fluid twice and new filter.
Any Ideas out there??
I have continued to try to get this tractor running without any problems. Before, it would idle for about 5 minutes before it bogged down and died or run about 2 minutes at higher speed before doing the same. I convinced myself it was not the motor and checked the 3-point lift to see if it was causing a "deadhead" and bogging down the motor. I found no problems with back pressure on the 3-point lift. I then thought maybe the HST transmission.
I tried driving the tractor and initially it continued to do the same thing - run a short time and bog down. If I waited about 30 seconds, it would fire up no problem. After trying this a few times, one day it suddenly just kept going as long as I kept it at idle. I drove around the yard and then let it sit at idle and it ran for 30 minutes before I turned it off. I have continued this and now I can run it a little above idle for extended periods, going forward, reverse, whatever, does not seem to matter. If I speed up the motor, then I get maybe 30 seconds before it bogs down and dies.
I assume the problem is in the transmission; somehow restricting flow at higher engine speeds. I have cleaned screens on both sides of transmission, with very little in the screens and changed out hydro fluid twice and new filter.
Any Ideas out there??
85Hokie
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BX-25D ,PTB. Under Armor, '90&'92-B7100HST's, '06 BX1850 FEL
Can you upload a picture of this? Like Lil Foot said - seems that this could be part of the problem? I have never turned my lever, never had a need to - but if it was turned 180 degrees or even 90 degrees out of whack - would that deadhead the system? The 3-point controlled from this? Or is this simply a way to add another loop in the hydraulic system?
kubotasam
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B2410, B7100dt, B7500,Woods BH750,Landpride 2660RFM, Tiller, B2781 Snowblower
How does it run with the clutch pushed in. If it acts the same with the clutch disengaged then the problem is not in the hydrostatic transmission.
North Idaho Wolfman
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I have checked this pretty closely and I do not believe there are any problems at this point. This is only used to "add another loop in the system." There is no back pressure on the 3-point system when not in use.
A picture is attached.
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It appears the input shaft into the HST continues to rotate with the clutch pushed in??? I will check this again. As I recall, the input shaft appears to slow down but does not come to a complete stop. I will see if I can apply a little back pressure, maybe stick on side of shaft with clutch depressed to see if it continues to turn. It appears that clutch is otherwise working OK, as I can easily shift from neutral, to high or low speed with the clutch in, but input shaft is always turning.
I am pretty certain that I have tried pushing the clutch in when it begins to bog down without any apparent change, which of course does not make any sense if it the transmission causing the back pressure.
I will head out shortly for some more tests. I have been missing around with this thing for so long now (on an infrequent basis due to work) that i cannot remember everything that I have observed over the last months.
I checked the clutch disengagement and it does appear to be disengaging, but there is still some drag. When you push in the clutch, you can see the input shaft into trans appear to slow down a bit. With the clutch push in fully, I pushed a hammer handle against the outside of the shaft and was able to bring it to a total stop with some pressure and the motor did not slow down with it at idle. I did install a new clutch and pressure plate with the overhaul and set the clutch linkage per the manual. With the clutch in, I am able to freely shift between high and low range, engage the PTO or shift into 4 x 4, so I think the setup is pretty close.
To Kubotasam's comment, I was thinking possibly there was enough drag on the clutch to stop the motor if restriction in the trans., but that is not the case. And, as you say, the problem does not appear to be in the trans. I ran the tractor for probably 20 minutes at a very fast idle while driving around. I went up a hill in high gear and may have slightly increased the engine speed and after a bit, the motor began to slow down. I put the clutch in all the way and the motor continued to die. I attempted to restart after a few seconds and starter could not turn over the motor. I waited about 30 seconds and it started right up, as is always the case. I drove back to the house with the motor at slightly slower RPM and no issues.
After getting back, I speed up the motor to I would guess to maybe 1700 rpm and after about 2+ minutes the motor began to slow down. I put in the clutch and no change. I quickly slowed down the motor with the throttle and this time it actually continued to run. Always before, the motor would die even if I attempted to slow it down and keep it running. It would appear that although both the machine shop and I checked all tolerances after the rebuild and a second time when I got worried and tore it back down that maybe the motor is just "tight" on the fresh overhaul and is starting to loosen up a bit. I does seem to be improving as I have been able to slowly run longer times and higher rpms. It is still a puzzle that it could appear to "freeze up" but then be just fine in 30 seconds. When I took the motor back apart after I first experienced this apparent "freeze up", there were no signs anywhere of any wear??
I guess I will just continue to drive it around, as that seems to be the most effective "repair" to-date.
I will note that it does have good oil pressure. I installed a new gauge to to make sure and it runs around 40+ psi.
I am curious if anyone can tell me what the bolt is with the double nut on top of the "frame", next to trans filter. I do not see any discussion of its function in the operators manual and there is nothing hooked up below but appears to be used to adjust tension on something.
To Kubotasam's comment, I was thinking possibly there was enough drag on the clutch to stop the motor if restriction in the trans., but that is not the case. And, as you say, the problem does not appear to be in the trans. I ran the tractor for probably 20 minutes at a very fast idle while driving around. I went up a hill in high gear and may have slightly increased the engine speed and after a bit, the motor began to slow down. I put the clutch in all the way and the motor continued to die. I attempted to restart after a few seconds and starter could not turn over the motor. I waited about 30 seconds and it started right up, as is always the case. I drove back to the house with the motor at slightly slower RPM and no issues.
After getting back, I speed up the motor to I would guess to maybe 1700 rpm and after about 2+ minutes the motor began to slow down. I put in the clutch and no change. I quickly slowed down the motor with the throttle and this time it actually continued to run. Always before, the motor would die even if I attempted to slow it down and keep it running. It would appear that although both the machine shop and I checked all tolerances after the rebuild and a second time when I got worried and tore it back down that maybe the motor is just "tight" on the fresh overhaul and is starting to loosen up a bit. I does seem to be improving as I have been able to slowly run longer times and higher rpms. It is still a puzzle that it could appear to "freeze up" but then be just fine in 30 seconds. When I took the motor back apart after I first experienced this apparent "freeze up", there were no signs anywhere of any wear??
I guess I will just continue to drive it around, as that seems to be the most effective "repair" to-date.
I will note that it does have good oil pressure. I installed a new gauge to to make sure and it runs around 40+ psi.
I am curious if anyone can tell me what the bolt is with the double nut on top of the "frame", next to trans filter. I do not see any discussion of its function in the operators manual and there is nothing hooked up below but appears to be used to adjust tension on something.
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Yes, the tanked is hooked up and the cap does have a small hole to allow venting. When the motor dies, you definitely hear it bog down and it emits some black smoke as coming under load. It will not turn over unless you wait about 20 to 30 seconds, so I am pretty certain it is not starving for fuel; has a totally different sound/feel than when you cut the throttle to kill it.
I just read through your entire thread for the first time. My first thought was that the starter was staying engaged and dragging down the motor. But since you can start it every time and haven't had trouble, I quickly ruled that out. My second thought, and now my leading concern, is the hydraulics. You say there is no backpressure, but I am still skeptical. Have you tried running the engine with the hydraulic pump disconnected? I would suggest disconnecting the hydraulic pump from the engine. Make a simple falt plate to bolt in place to keep dirt out and the oil in. The bearing is only under splash lubrication, so no excessive oil pressure to worry about. With the hydraulic pump disconnected, it can definitely ruled out the hydraulics as a problem, or definitely point to the hydraulics as the source of the problem.
I work on Kubota diesels a lot, and on a few occasions have test ran an engine with a seizing hydraulic pump. It definitely puts the engine under load, and make a bad sound while doing so.
I work on Kubota diesels a lot, and on a few occasions have test ran an engine with a seizing hydraulic pump. It definitely puts the engine under load, and make a bad sound while doing so.
Thanks for the suggestions. In these cases, was the seizing occurring the entire time you were running the motor? Mine is just fine for awhile and then suddenly comes under load. After waiting about 30 seconds, then no load on the motor.
After I put the motor back together for the second time, I built the makeshift engine stand and ran the motor without it hooked up to trans or hydraulics (pump on motor, but lines not attached). This was awhile ago now and I cannot remember for certain if I shut off the motor or if it eventually died on its own. I do know it ran for a while and much longer than it was running before. At the time, I was not sure why the improvement as I did remove a slight bit more from the rings to increase end-gap. I don't think it was the change in the end-gap but thought it more likely related to something connected to the motor (hydraulics or trans.). The guy at the machine shop, who has a lot of experience also thought it more likely it was some other than the engine causing the load.
I checked the pressure on the hydraulic line running from the pump to the connection beneath the seat. There was essentially zero pressure as the motor ran and would get a slight bump as I raised the three-point lift. At the top of the lift, the pressure would spike and then the lift lever would be returned to the neutral position at which point the pressure went back to zero. I do not hear any noise or otherwise signs of problems with the pump. During all of this time, I could usually get the motor to idle for up to 5 minutes before bogging down and dying.
I shifted my focus to the transmission and at first when I tried to drive the tractor, I had the same symptom (idle for 5 min and die, or run shorter time if higher rpms). I have kept at this every weekend or two for the past couple of months. I would just do it for a short time and put it back in the barn. A few weeks ago, I decided I would just keep at it until one of us gave up. That day, the tractor did not die on the first attempt, I just kept driving around the yard (at idle in low range) and then let it sit at idle for probably 30 minutes total. If I went much faster, then it would die. Now, a couple of weeks later and after several more runs of 30+ minutes, it will run indefinitely at a fast idle, I would guess may 1,000+ rpm. Another change that I have noticed is that it does not die as quickly and seems to bog down with less restriction. Yesterday, for the first time I was actually able to keep it running by slowing it back down to idle when it tried to die after running at faster speed. Before, it did not matter, once it started to die (bog down), you could not do anything to stop it from dying.
This improvement after driving it around, made me think that somehow it was related to the trans, as I believe the tractor sit for sometime before I bought it and rebuilt the motor. However, as Kutobasam noted above pressing in the clutch does not appear to have any impact.
I will take at look at hydraulic pump to see if I can separate it from the motor while keeping the lines attached. Otherwise, as I seem to recall from past attempts along this line it still pumps hydraulic fluid out of the lines; I guess pressure from the trans???