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Cat 247 lost all hydraulics

Dirt Surgeon

Member
Joined
Feb 12, 2023
Messages
8
Location
Southeastern Virginia
Hey guys. Any help is much appreciated. My cat 247 was having issues recently having weak lift arm function. Everything else worked fine. Today we were running the machine and lost all hydraulics all of a sudden. The hydraulic fan isn't spinning either. I pulled the pump away from the engine and the coupling seems to be fine. At least the teeth seem fine. Very Little wear. Any suggestions?
 

Nige

Senior Member
Joined
Jun 22, 2011
Messages
28,984
Location
G..G..G..Granville.........!! Fetch your cloth.
Did you lose drive to the wheels at the same time as losing implements and the fan stopping.?
If you did then the coupling #1 as indicated above by HMC is what's failed.
Serial Number is always good to correctly identify parts.
 

Dirt Surgeon

Member
Joined
Feb 12, 2023
Messages
8
Location
Southeastern Virginia
CML00475 is serial number.
Yes lost everything at same time. But about a week ago my lift arms got super weak. I was thinking stuck relief valve. Then today this happened. So I pulled it apart and the teeth on number 5 and number one in the above picture look fine. How do I tell if the coupler has failed and not my pump. No I have not checked pressure.
 

Dirt Surgeon

Member
Joined
Feb 12, 2023
Messages
8
Location
Southeastern Virginia
Did you lose drive to the wheels at the same time as losing implements and the fan stopping.?
If you did then the coupling #1 as indicated above by HMC is what's failed.
Serial Number is always good to correctly identify parts.
Yes. Lost drive/implement/fan all at once. How do I tell if the coupler failed? It looks fine to me. As in no unusual wear on teeth. And allen bolt isn't sheared.
 

Nige

Senior Member
Joined
Jun 22, 2011
Messages
28,984
Location
G..G..G..Granville.........!! Fetch your cloth.
Do you have enough space to remove the hub #5.? If you can remove it then stick it into #1 and try to turn #5 by hand.

TBH losing drive, implements, & fan at the same time is generally an indication of a failed coupling. Furthermore if in the unlikely event that it is the pump you would be mad not to install a new coupling at the same time as you replaced said pump.
 

Dirt Surgeon

Member
Joined
Feb 12, 2023
Messages
8
Location
Southeastern Virginia
Do you have enough space to remove the hub #5.? If you can remove it then stick it into #1 and try to turn #5 by hand.

TBH losing drive, implements, & fan at the same time is generally an indication of a failed coupling. Furthermore if in the unlikely event that it is the pump you would be mad not to install a new coupling at the same time as you replaced said pump.
I have hub #5 off. I will attempt to stick it in #1 tomorrow and let you know. If it is the pump would I replace both the tandem pump as well as the smaller charge pump on the front? What is both of their functions?
 

bobatack

Well-Known Member
Joined
Feb 20, 2012
Messages
87
Location
Ontario, Canada
Nige might say otherwise
IIRC then item #5 can become loose on shaft and slide far enough endways to disengage from item #
 

Dirt Surgeon

Member
Joined
Feb 12, 2023
Messages
8
Location
Southeastern Virginia
I didn't get a chance to get by the machine today. I went ahead and ordered a new flange, coupler and bolt. Hopefully I'll have time to install it tomorrow. I'll let yall know. Thank you for your help.
 

Dirt Surgeon

Member
Joined
Feb 12, 2023
Messages
8
Location
Southeastern Virginia
Hey guys thanks for all the help. It ended up being the charge pump that mounts to the front of the twin piston pump. The pump failed and locked up, shaft sheared in two. So I ended up replacing the coupling anyway while i had it apart. And Installed a new charge pump and good to go.
 
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