Bobcat s175 lift problem

[Dave3517]

I have a 2005 bob at s175 with the foot controls for the bucket. I am having a problem lifting it doesn't seem to have the lifting power it had before I pulled out a bunch of bushes in front of the house. It used to lift the back tires right off the ground if you tried to lift something to heavy now the bucket goes up untill there is to much weight and stops and won't lift rear tires off the ground. With no weight it will rise up all the way. The engine does not seem to bog down when there is to much weight the bucket just doesn't go up any more once in a while it works great and lifts rear tires right up but not that often.

 

[Ryanrb25]

I dont know where it is on that particular machine but i'd be checking the spring in the relief valve first.

 

[Dave3517]

I will check the relief valve spring as soon as I find out where it is. Thank you for giving me a place to start.

The lift arms do not lower on there own unless it's over night then they go down on there own. For the past year at high rpm's when I tilt the bucket there is a loud humming noise I don't know if that has anything to do with my problem. Thanks again

if anyone knows where the relief valve spring is located please let me know

 

[Farmereinar]

start simple, make sure your belt is adjusted right, any slack in the hydro drive belt will cause that, mine would work fine until i lifted something a little heavy or pushed into a pile, the motor wouldnt bog but hydraulics would slow down, turned out to be the belt

 

[Dave3517]

Thank you all for your help. I stopped by the bobcat dealer by me to ask about this. They also said to check the belt. I checked the belt and the tentioner is broke I adjusted it for now so belt is tight but there is no spring tention. everything works great now. I am going to replace tentioner and belt. Does anyone know where to get the best deal on the tentioner and belt. Bobcat deal seemed kinda high on other prieces. Thank you all again for you help

 

[ValleyFirewood]

If it was an engine part you could try the Kubota house, but for that tensioner it's probably gonna be a Bobcat part. In my experience it is what it is on those parts.

I searched online for an aftermarket source and didn't come up with anything. Probably not an item commonly replaced.

 

[Dave3517]

I was using my bobcat again today and i am having the same problem again not much power lifting. i was digging into a hill and when i was lifting dirt with the bucket i couldnt rip through tall grass. it has a swish sound by where the pump is almost like a check valve or release valve isnt closing all the way. shouldnt the bobcat stall or bog down if your lifting too much. Does anyone have diagram of the hydraulics for the S175. thank you

 

[willie59]

I can in no way say for certain what your problem is, but as you describe things, doesn't sound like a lack of drive belt tension as you don't describe a problem of loss of power under a load of all three functions combined, i.e., drive, bucket tilt, loader arms, and drive. Likewise, since drive doesn't seem to have an issue, leaving us with a problem of loader functions, you don't describe a problem with bucket tilt breakout force, right? If so, no issue with bucket power, leaving us only with loss of power (force) of loader arm functions, logic indicates problem is isolated to loader arm circuit. If all this is correct, belt is not the problem, neither is the main relief valve for loader control valve, seems to indicate problem with either port relief valve for loader arms or failed piston seals in one (or both) loader arm cylinders. Just the thoughts in my cluttered head.

 

[Dave3517]

The drive works great the tilt also works the way it should once and a while it doesn't lift if your driving and tilting a heavy object. The belt is tight so the belt is not the prob. Some kind of valve is closing all the way is what I think. I just don't know where to find those valves to check them. Again thank you for your ideas saves me a trip to bobcat dealer.

 

[willie59]

Raise the cab and rest it on the safety prop. You need to remove the port relief valve cartridge and the BICS lock valve cartridge for the loader arm lift circuit and inspect the o-rings on the cartridges. And if it were me, while I have them removed, I'd put new o-rings on them anyway. This is a control valve for a T250, but it should be similar to your control valve. The BICS lock valve is noted by a 1 in the pic, the port relief valve is noted by the red arrow. Make sure the loader arms are fully at rest on the ground before removing these valves.







If that doesn't fix your problem, I think I'd pull the lift cylinders and go through them with new seals. Hopefully you'll get this thing sorted out.

 

[Dave3517]

I took a look last night my pump looked a little different but I did take out a couple valves that had wires going to them. One of the ones I pulled out was wet with oil around it. the small screen that went around part of it was streched out and bent and looked like it had some sludge vary little amount on the end. It was located on the right side of the pump about in the center. Bobcat seems to be working better. Not sure if it was the right things to check.

 

[willie59]

If you were working on a manifold with a solenoid valve that's attached to the outlet port of the work equipment pump, that would be a Power Bobtach control valve. I can't say how the solenoid spool inside that valve would affect loader arm operation, can't say it's not possible either, just doesn't seem like it would be the problem since you have no problem with bucket tilt function. :beatsme

 

[Dave3517]

The valve I took out had a alluminum nut at the end then the part that had the wires coming off it slid off then a deep 19mm socket took the valve out. I don't know if it had anything to do with the problem I'm having or not. I just saw that there was a very small leak. It seems that the machine lifts better when cold then again maybe I'm just trying to do to much with it. Yesterday when I was using it digging into a sand pile it seemed to work good when lifting to much and driving the machine bogged and almost stalled. That is the way it used to be all the time. All of you guys have been a big help and I thank you. If anyone has any other ideas feel free. I will take an other look to see if I can find the other two valves in the picture above they may be on the bottom of the pump I couldn't see under the pump without a mirror

 

[willie59]

I will take an other look to see if I can find the other two valves in the picture above they may be on the bottom of the pump I couldn't see under the pump without a mirror

I'm not sure why you're working in the pump area, you don't seem to have a problem with the pump as the tilt works fine, the loader arms (occasionally) work, and you haven't reported a problem with low pressure at the auxiliary circuit. The valves I referred to are located in the main hydraulic control valve.

This is an older machine, but your main control valve should be in the same location (see red arrow in pic).

 

[Dave3517]

Willie59 I am sorry I keep calling the main hydro valve the pump very sorry. It has been the main valve I have been working on the hole time. Yes mine is in the same place as the picture. It look a little like the one in the picture. Thank you for your time it is a very big help.

 

[willie59]

No worries Dave, but keep in mind, the only mental picture we can get is what you describe, and terminology is very important in that respect.

From what you describe in post #11 sounds like one of the auxiliary control valves that you removed. If that's the case, you're going after things that aren't related to the loader arm circuit. The two things I said you need to pull is the loader arm circuit port relief valve and pilot lock valve, neither of these have wires going to them. I'm curious to hear what you find when you pull them, hopefully you find something.

 

[Asm24]

man I got the same problem did u ever figure it out?