Bought dozer with inoperable winch. Have replaced both cables, replaced filter element, cleaned magnetic strainer. Had no debris in strainer. Drained and replaced oil from winch reservoir. There was no metal or clutch contaminates on magnetic drain plug. Winch still inoperable. Pulled hydraulic pump off torque converter housing. Verified it pumps oil. Verified pump shaft coupler to converter input shaft is good, holds on both sets of splines. Reinstalled pump. Primed big pump return hose and pressure hose to winch and reattached to pump. Put 600 psi pressure gauge on plug J and K of valve body. Still no pressure. Is there a way to check pressure at pump? Any help appreciated.
It is a 1979 Cat D7G dozer
Are you getting any oil pressure at all at test port #3 (test port for lubrication circuit) should be reading about 40 psi, engine at high idle, lever in hold position. Ports #1 & # 2 reading zero. Are the cable controls adjusted for prop[er travel.
My paperwork shows two ports however the pictures are poor quality. They say Port J for input clutch and Port K for direction clutch pressure. Attached is a picture of the hydraulic control valve body with what I think are Port j and k marked. My pictures don't have a lubrication Port marked. Can you tell me where the lube Port is. Will the lubrication port have a reading if my cables are out of adjustment?
Can I check winch hydraulic pressure at the Port in the picture attached.
Found the lube Port.
Yes, you can check pump pressure at that point and you need 300psi at input clutch, 270psi at direction clutch. If you have sequencing valve J should make 265psi and K 220psi at low idle. Lube pressure regardless of cable adjustment.
Performed pressure test at test port on hydraulic pump and was getting 30-35 psi at high idle with gauge fluctuating. Also got 30psi at lube Port on valve body but 0 pressure on brake and clutch port. Removed and disassembled the hydraulic pump found bushings and gear teeth in good condition. Shafts are tight in bearings. No wear in pump body pockets. No wear on end plates. Have concern of possible leak on suction side of winch to pump. Is there a way to pull vacuum on large return hose to hydraulic pump to see if it pulling oil from winch sump correctly. Used shop vac and pulled vacuum on large pump suction hose and did retrieve oil in vacuum canister. Any suggestions on verifying if I have leak on suction side before I buy new pump?
Is this seal installed correctly? Lip of seal is facing outward toward converter flange/winch mount flange, you would think lip seal would be the other direction to hold pressure inside of pump.
All shafts and bearings are tight and gear teeth in good condition.
Seal orientation is correct. At engine high idle and lever in hold position there should be no pressure to either clutch and the lube pressure should be about 40psi. Not until you engage lever to wind does the pressure climb with max approx 300psi. If you get no pressure at directional clutch there is a problem in the control valve. Either the load piston or spool is stuck/not moving. There may be a problem with no oil flow to load piston through its passage. or there is no pressure in the directional clutch. No pressure at input clutch is either a failure of the control cable or linkage or its spool will not move. Checking suction hose is just a matter of fittings that will allow vacuum of the disconnected hose. Again you need to resolve pressure issue with pump and have cable adjustment correct. What is the clearance between the pump teeth and the housing and the actual end clearance of the gear to housings.
yes what OM said check cable adjustment is correct. On these winchs, oil disengages the opposite clutch for direction. And engages input clutch. Diectional clutchs are spring applied, pressure released. In effect this is the winch brake, as both clutchs are engaged. One releases for drum movement. Input clutch is the weak link on these cat winchs; but at least they are easy enough to remove and repair