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Old 623 elevator pan. Want paddle to load

chris allen

Senior Member
Joined
Feb 11, 2014
Messages
372
Location
georgia
Occupation
Feild tech
Our machine is giveing us fits. Our elevator will opperate in reverse just fine but barely moves in forward position to load. Have to get engine rpms really high to barely get any forward movement. Only moves in the high position An nuthin is the slow speed Have pulled the valves outta the elevator valve body on fender behind cab to make sure nuthin was stuck An didn't find anything outta wack , both metal tubes that run up the hitch to the elevator drive motor are sitting there chattering like crazy while just sitting there Sounds like both lines are working against each other. There's 2 small lines that go from the elevator joystick control valve to behind cab to big elevator control valve body. I tryed switching the 2 lines with each other to see if it reverse functions but it made no difference in operation. Any ideas
 

oregon96pd

Well-Known Member
Joined
Mar 14, 2009
Messages
173
Location
Milton Freewater, OR
Our 615 did that and it was the rod that all of the control levers are mounted to. The cotter pin had fallen out and let the rod slide to one side and the linkage wouldn't make a full movement at the valve. Might be worth looking at, what model of 623?
 

RZucker

Senior Member
Joined
Jul 7, 2013
Messages
4,077
Location
Wherever I end up
Occupation
Mechanic/welder
Pull the motor and check the Vanes and Cam ring. I've seen the vanes chip on the forward side of the rotation and run fine in reverse. and if the Cam ring has any chatter marks its junk. A complete cartridge is the way to go.
 

chris allen

Senior Member
Joined
Feb 11, 2014
Messages
372
Location
georgia
Occupation
Feild tech
Took lines on the elevator motor An flipped them An the forward works now but now no reverse. Pulled complete valve body outta machine An looked at the forward an reverse spools an all look fine
 

DPete

Senior Member
Joined
Feb 21, 2007
Messages
1,677
Location
Central Ca.
Not sure what model you have but my E and F had a directional control valve at the speed reducer, one had a broken spring inside and did like you describe.
 

Mark250

Senior Member
Joined
Aug 30, 2015
Messages
1,243
Location
victoria,Australia
Occupation
heavy equipment technician
not sure what model you are talking about but from your description I would guess a 623B with 46P prefix
the chattering hydraulic hoses to elevator motor normally indicates the coil springs under the motor vanes have broken which is quite common you usually find the bits in the hydraulic return filter when doing a service.
in your case it sounds like the elevator flow control valve has a plugged orifice in the dump spool this is quite easy to check as the valve is on top of the elevator control valve
be aware the elevator system uses three main relief valves .the relief valve on the main control valve is used for elevator reverse and the combination relief and flow control valve on the elevator control valve is used for forward one and two each pump section the control valve has its own relief valve
flow control valve.png Untitled.png
 

chris allen

Senior Member
Joined
Feb 11, 2014
Messages
372
Location
georgia
Occupation
Feild tech
My 623 is a old one. It's serial prefix is 52u. Pulled control
Outta machine today an disassembled it An pulled all three spools outta main valve body. Didn't see anything broke or worn out. So we reassembled valve an replaced to machine. Had took both main lines off elevator An switched the forward an reverse lines with one another An then the elevator will turn forward. But then when I pull the lever to make rotate in reverse it starts acting up in reverse then. Acts as if something going on in the main elevator valve body that's mounted on fender behind cab. Have tooked that control
Valve out An went threw it to An found nuthin broke or bent
 

chris allen

Senior Member
Joined
Feb 11, 2014
Messages
372
Location
georgia
Occupation
Feild tech
Just outta curiosity I pulled the elevator drive motor off An pulled apart An looked over the cartridge veins inside. There was some scoring on the forward inlet end of cartridge An on end cap. Reverse end had very lil wear. Didn't look to be enuff to say it was shot. Specially since it pedaled fine when hoses were flipped Still
Got the forward line still chattering back to control valve behind cab An to Hyd pump
 

chris allen

Senior Member
Joined
Feb 11, 2014
Messages
372
Location
georgia
Occupation
Feild tech
Well guys got with a ole friend that still works for cat An talked to him few minutes bout my issues. He wasn't familiar with a pan this old But he had some
Legacy files (in which are old service manuals from back in the day that we're printed to the PDF files for computer). So he looked up the Hyd section on my 623 An emailed me the Hyd part of files. Was very helpful , learned that the machine has cartridges in its pumps An the pump that controls the steering of the machine an the forward of the elevator, an another pump one half controls the bowl an ejector An the other half is the elevator reverse. Would of never guessed that. So I pulled pump off for steer An forward elevator drive An took apart to find that the cartridges were all screwed up An the bolts that hold them together were broken in several differ peaces plus there were deep gouges in end plates were the bronze plated areas are on end cap. So hopefully new cartridges we talk care of my issues. Never hurts to have good guys out there to share some ole school knowledge. Getting harder everyday to find information on old equipment
 

Mark250

Senior Member
Joined
Aug 30, 2015
Messages
1,243
Location
victoria,Australia
Occupation
heavy equipment technician
glad you got it sorted ,BUT
this is a classic example where not all the information is shared, first NO SERIAL NUMBER so I wasted MY TIME responding to what I guessed the serial number might be ,given the information supplied . Bad guess
Second the steering issue was not mentioned which would of been a give away to what THE PROBLEM WAS, as all the early scrapers run multiple pumps
I also have access to the information for the serial number given AFTER I POSTED
but decided to opt out at that point.
Mark
 
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