I would check the dampners on the steering linkage.I would re do the ten on the belt and check fluid and filters
first thing. does it creep? fire it up seat bar down push the button, does unit try to drive?I would check the dampners on the steering linkage.
Dampners are fairly new and I have recently replaced all the "centering" slides and bearings. It does not try to creep on its own. It's more of a shutter than a vibration and it doesn't do it all the time. I can run the machine at WOT for half hour or more and it may start doing the shutter. I can feel the shutter in the seat but if I let go of the control sticks I can see the sticks shuttering. It stops as soon as I throttle it back slightly and then I can go back to WOT and it's fine for a bit. If I run the machine at slightly less than WOT it won't do it. I'm leaning towards something going on with the drive belt tensioner. I also thought it maybe motor mounts but I put new rear mounts in (didn't feel like battling with the fronts) and still no change. I am just looking for ideas. I'll figure it out but it may take more of a "failure" to find the problem. I'm pretty in tune with my machines and I know something is not right. I like to stop small problems before they become big (expensive) problems. Plus, it always breaks when I need the machine the most.I would check the dampners on the steering linkage.
I wonder if your hydraulic fluid is cavitating a bit.Dampners are fairly new and I have recently replaced all the "centering" slides and bearings. It does not try to creep on its own. It's more of a shutter than a vibration and it doesn't do it all the time. I can run the machine at WOT for half hour or more and it may start doing the shutter. I can feel the shutter in the seat but if I let go of the control sticks I can see the sticks shuttering. It stops as soon as I throttle it back slightly and then I can go back to WOT and it's fine for a bit. If I run the machine at slightly less than WOT it won't do it. I'm leaning towards something going on with the drive belt tensioner. I also thought it maybe motor mounts but I put new rear mounts in (didn't feel like battling with the fronts) and still no change. I am just looking for ideas. I'll figure it out but it may take more of a "failure" to find the problem. I'm pretty in tune with my machines and I know something is not right. I like to stop small problems before they become big (expensive) problems. Plus, it always breaks when I need the machine the most.
I did recently reseal a drive motor and replace all hydraulic fluid. However, the shuttering was occurring before this repair. I am going to try to pull it in the shop today or tomorrow and look for the problem. I'll let you guys know if I find anything. Thanks for the replies and if you guys can think of anything else I need to look at let me knowI wonder if your hydraulic fluid is cavitating a bit.
update. I started to tare into the Bobcat today to try to figure out the problem. I focused my attention on the drive belt tensioner. Upon immediate inspection I found that the tensioner stop was not even close to being adjusted correctly. I took the air filter assembly out and also the battery so I had room to work. Once I loosened the tensioner it did not seem too bad, however, it did not rotate on it's pivot (to apply tension to the belt) like it should. I removed the tensioner assembly from the loader and found a bunch of old dried up grease on the pivot. The bearings in the tensioner idler also felt the slightest bit rough. I removed the bearings and I am now waiting on new ones to show up. I will update again when I have it back together. Hopefully I am going in the right direction.I did recently reseal a drive motor and replace all hydraulic fluid. However, the shuttering was occurring before this repair. I am going to try to pull it in the shop today or tomorrow and look for the problem. I'll let you guys know if I find anything. Thanks for the replies and if you guys can think of anything else I need to look at let me know
Sounds good to me take a good look at the spring might be a good time to replace it tooupdate. I started to tare into the Bobcat today to try to figure out the problem. I focused my attention on the drive belt tensioner. Upon immediate inspection I found that the tensioner stop was not even close to being adjusted correctly. I took the air filter assembly out and also the battery so I had room to work. Once I loosened the tensioner it did not seem too bad, however, it did not rotate on it's pivot (to apply tension to the belt) like it should. I removed the tensioner assembly from the loader and found a bunch of old dried up grease on the pivot. The bearings in the tensioner idler also felt the slightest bit rough. I removed the bearings and I am now waiting on new ones to show up. I will update again when I have it back together. Hopefully I am going in the right direction.
so this is how I handle drive belt teninosers. and I do this every time I got one on the bench. A . place in vice, b. pb blaster. c turn vice handle to compress spring, note vice grip handy to keep it secure., sometimes you got to tap with hammer to get it to move. open and close a few times. wipe with never seize, {you are going to see the pivot pin work thru the the half moon] if its got divots or brgs have excessive play . suck it up and replace it . trick . most of the time they wont cam over from starting point. so when installed its a bitch. remedy is to preload while in vice cut the end off a zip strip, and place between pin and start point giving a slight pre load. install it put belt on if new belt ? bottom out teninsoer. 3 oclock plus. may have to apply down pressure and tap big gold cover with hammer to get it to cam over. LOCK IT DOWN DEAD head AGAINST BRAKE> belt is now stretched and should be in happy placeSounds good to me take a good look at the spring might be a good time to replace it too
I think you may be referring to a different type of tensioner??? The spring on my loader is a long spring that stayed in the loader when I removed the tensioner.so this is how I handle drive belt teninosers. and I do this every time I got one on the bench. A . place in vice, b. pb blaster. c turn vice handle to compress spring, note vice grip handy to keep it secure., sometimes you got to tap with hammer to get it to move. open and close a few times. wipe with never seize, {you are going to see the pivot pin work thru the the half moon] if its got divots or brgs have excessive play . suck it up and replace it . trick . most of the time they wont cam over from starting point. so when installed its a bitch. remedy is to preload while in vice cut the end off a zip strip, and place between pin and start point giving a slight pre load. install it put belt on if new belt ? bottom out teninsoer. 3 oclock plus. may have to apply down pressure and tap big gold cover with hammer to get it to cam over. LOCK IT DOWN DEAD head AGAINST BRAKE> belt is now stretched and should be in happy place
I replaced the bearings in the drive belt tensioner and guess what....no change. The shake/shimmy is still there occasionally. Hmmmm. Maybe I am getting some pump cavatation? What can I do to check for cavatation? I am going to raise the cab today and take a look for other possibilities.I think you may be referring to a different type of tensioner??? The spring on my loader is a long spring that stayed in the loader when I removed the tensioner.
Did you replace the springI replaced the bearings in the drive belt tensioner and guess what....no change. The shake/shimmy is still there occasionally. Hmmmm. Maybe I am getting some pump cavatation? What can I do to check for cavatation? I am going to raise the cab today and take a look for other possibilities.
The spring looked to be in good shape. I have the shop manual and it does not give any specs as to when the spring should be replacedDid you replace the spring
Easiest way to check for cavitation is look at the hydraulic oil when it acts up. If the oil looks foamy in the sight glass, it is airated. Possible causes are either air is entering the system on the suction side, or the gear pump is going.The spring looked to be in good shape. I have the shop manual and it does not give any specs as to when the spring should be replaced
my bad on wrong belt ten style though I must admit great advice on other style . on yours there is a mechanical stop located above bell house cover that does need adjustment. im sure you have seen it probally had to remove to replace belt. not seeing this a a stick feed back issue though. so questions remain .my first inclatition would be low charge pressure though no mention of charge press codes.. can we differanite between left and right or forward or rverse would be next in line as to questionsEasiest way to check for cavitation is look at the hydraulic oil when it acts up. If the oil looks foamy in the sight glass, it is airated. Possible causes are either air is entering the system on the suction side, or the gear pump is going.
Follow up: So I looked into the machine further and everything seems to be good. Motor mounts are good. all belts are tight. Cooling fan is fine. All fluids are good. Hydraulic filter was replaced about 100 hours ago. While I do not know what the charge pressure is, it seems fine. There are no codes and everything operates like it should. I used the machine for about an hour yesterday and the problem seems to be much better than before. It only started shaking once and it wasn't too bad. I didn't even have to idle it back to stop the shake. It didn't do it for the last 45 minutes I used it. Maybe it was the belt tensioner. For now I'm just going to continue using the machine. No way am I going to tare into the machine any further just trying to hunt down this minor annoyance. Thanks for your help.my bad on wrong belt ten style though I must admit great advice on other style . on yours there is a mechanical stop located above bell house cover that does need adjustment. im sure you have seen it probally had to remove to replace belt. not seeing this a a stick feed back issue though. so questions remain .my first inclatition would be low charge pressure though no mention of charge press codes.. can we differanite between left and right or forward or rverse would be next in line as to questions
I would go ahead and buy a new spring and belt for next timeFollow up: So I looked into the machine further and everything seems to be good. Motor mounts are good. all belts are tight. Cooling fan is fine. All fluids are good. Hydraulic filter was replaced about 100 hours ago. While I do not know what the charge pressure is, it seems fine. There are no codes and everything operates like it should. I used the machine for about an hour yesterday and the problem seems to be much better than before. It only started shaking once and it wasn't too bad. I didn't even have to idle it back to stop the shake. It didn't do it for the last 45 minutes I used it. Maybe it was the belt tensioner. For now I'm just going to continue using the machine. No way am I going to tare into the machine any further just trying to hunt down this minor annoyance. Thanks for your help.
I've used the machine quite a bit the last couple of days and I'm pleased to say that the vibration is gone! I guess it was the drive belt tensioner.I would go ahead and buy a new spring and belt for next time
