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catmastertech, Technician
Category: Heavy Equipment
Satisfied Customers: 2355
Experience:  19 years Cat, 3 years Case
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I just bought a cat 518 skidder (old, cable type) and the winch

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I just bought a cat 518 skidder (old, cable type) and the winch will spool in, but not out. The winch control lever feels normal when you ask for 'in', but feels like there is no hydraulic pressure when you ask for 'out.' Is there a way to reverse the lines so I can check the control valve for proper operation? Any suggestions for isolating the problem otherwise.

I don't think your winch has a power out mode. Most of the skidders did not.

If I am wrong about this please send me your serial number and I will dig into the model you have. I have some information on winches attached. If you winch is different include the winch model and serial number with your reply. It is stamped on the winch but, I am not sure of the exact location.

518 winch operation.

Customer: replied 6 years ago.
I think you are right. I may have misunderstood the seller when he said it "winched out". I have seen many skidders work and they all 'freewheel' when you pull the main winch cable. The winch and controller look exactly like the info you sent me. I am grateful to have it. Can you suggest as to why the winch would spool in smoothly and not freewheel under a fairly substantial strain. I busted a 6000 lb. rope like it was a shoestring trying to break the spool loose. I am a fair mechanic and this machine seems fairly simple and well designed. I just hate to work on the wrong end of a problem if good advice can start me in the right place. Thanks so much again.


Here is more on the later models, these are usually CAT made winches and were very common in my area.

I would guess your brake release is not working correctly. Check this info and see if it won't help understand this unit.

Winch operation


Here is the testing book also.


Winch Testing


Let me know if this is not correct, the serial number may help if it is not. I will try to find other information.


Here is info for the older Gearmatic winch, it has more cast iron in its housing and is rounder shaped.


Gearmatic winch testing.


Either way you should be covered.



catmastertech and 2 other Heavy Equipment Specialists are ready to help you
Customer: replied 6 years ago.

The first link you sent me worked really well. I pulled the primary cover on the clutch and brake side and found the brake not working. I traced the problem back to the master control. My neighbor, who is also a fair mechanic, helped me, and we were able to use the three pages you sent us to save several hours of diagnostics. We were able to reverse the lines, release the brake, spool the winch drum out, and, after returning the lines, spool the cable in under power.

I know exactly which parts I need now and will be able to rebuild the hydraulic control system from the winch back. It should be as good as new.

Thanks tons,


Glad to hear that, thanks for the reply.

Let me know if I can help you again.

I did like the simple design of the 518, it only has some tough spots to work on. The rest of the machine is solid as long as it doesn't use wide tires.

Important note: Replace the u-joints every year in the center section or it will fail and damage the transmission housing.