bobcat 643 strange noise.

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Bobcatt643

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Hellow. I have the same Bobcat as the videon and mine makes the same noise when tuning left or right. And in the video you can hear it at the end when he turn it off. Its like scrape of metal on metal. If someone know whats making this noise ill be glad to fix it. https://www.youtube.com/watch?v=jRc39-x84mI
 

Tazza

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Are you running the machine at 1/2 to 3/4 throttle? at low speed, it is louder, but that noise is not uncommon.
 
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Bobcatt643

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Are you running the machine at 1/2 to 3/4 throttle? at low speed, it is louder, but that noise is not uncommon.
Even in full trottle it still makes it. When the machine is without the bucket it better but when i put the bucket ant it is full when you try to turn left or right it is a nightmare. It seems to make it when tha machine has a lot of down force and the drive motor have a lot of load
 
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Bobcatt643

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Even in full trottle it still makes it. When the machine is without the bucket it better but when i put the bucket ant it is full when you try to turn left or right it is a nightmare. It seems to make it when tha machine has a lot of down force and the drive motor have a lot of load
is it possible air in the system to make this noise.
 

Tazza

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is it possible air in the system to make this noise.
Air would make noise, but it should bleed out pretty fast.
It could be pump wear causing the noise too.
How is the drive power? if you drive up to a tree or other object tht will not move when you push it. See if you can get the wheels to spin in the dirt, you will probably get only one side to move at a time.
If it won't move, your pump sounds like it's weak, if you have mechanical abilities and willing to crack open the pump, you can tidy it up and get it back to how it should be.
 

mmsllc

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Air would make noise, but it should bleed out pretty fast.
It could be pump wear causing the noise too.
How is the drive power? if you drive up to a tree or other object tht will not move when you push it. See if you can get the wheels to spin in the dirt, you will probably get only one side to move at a time.
If it won't move, your pump sounds like it's weak, if you have mechanical abilities and willing to crack open the pump, you can tidy it up and get it back to how it should be.
I have seen loose hydraulic filters cause air infiltration into a sealed system. They can be loose to the point where suck in air, but not leak fluid out. Seems very counter intuitive, but if you ever see it / hear it, you will never forget it. Try looking at the hydraulic fluid to see if it is foamy or not. If it is, then you have air in the system causing the noise issue. It is a very simple check to see what you have going on.
 

mmsllc

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I have seen loose hydraulic filters cause air infiltration into a sealed system. They can be loose to the point where suck in air, but not leak fluid out. Seems very counter intuitive, but if you ever see it / hear it, you will never forget it. Try looking at the hydraulic fluid to see if it is foamy or not. If it is, then you have air in the system causing the noise issue. It is a very simple check to see what you have going on.
it could also be a blocked / plugged up hydraulic filter. I'd change it & hope it works better. If it does, try to carefully open the filter to see what debris is inside. It'll help to see in order to know where to go next.
 
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Bobcatt643

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it could also be a blocked / plugged up hydraulic filter. I'd change it & hope it works better. If it does, try to carefully open the filter to see what debris is inside. It'll help to see in order to know where to go next.
The power is ok. If i put the machine against a wall it spins the boths sides on a concrete. I notice that the hydrostatic pump geting very hot after bit of work. What about the bronze filter iz it posible if it is filthy? Is it posible to be from it
 

Tazza

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The power is ok. If i put the machine against a wall it spins the boths sides on a concrete. I notice that the hydrostatic pump geting very hot after bit of work. What about the bronze filter iz it posible if it is filthy? Is it posible to be from it
If you can spin the wheels, your pump is good.
Is there a square block on top of the hydraulic pump?
 
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Bobcatt643

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Make sure that filter is spotless, i think they are cheap from the dealer too. If they get restricted, the pump will scream and get hot fast.
is there any difference between hydro pump in bobcat 630 and 643? Ive order bronze filter for my 643 and the filter that came is different from mine, it is for 643 but mine is the same type like in 630. Can you put filter for 630 in 643. The original for 643 is with a little screw on the top. Now i dont know what to do, to order one for 630 or to try to put this one for 643 an to order some tube to install it. How to understand from what model is mine it is possible that this is not the original pump or only the squre block for the bronze filter is from 630.
 

Tazza

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is there any difference between hydro pump in bobcat 630 and 643? Ive order bronze filter for my 643 and the filter that came is different from mine, it is for 643 but mine is the same type like in 630. Can you put filter for 630 in 643. The original for 643 is with a little screw on the top. Now i dont know what to do, to order one for 630 or to try to put this one for 643 an to order some tube to install it. How to understand from what model is mine it is possible that this is not the original pump or only the squre block for the bronze filter is from 630.
I believe the only difference was the filter length. If it fits, it should be ok.
I wonder how important the filter is, the newer machines don't have this filter, only the main filter. So really...... I don't think this filter is NEEDED but extra filtration is always a good thing, but if you need to run it without, i'd think you could let the main one do all the work.
 
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