John Deere 490 travel issues

[jchand4]

Hey all I’m new to the forum but have been lurking for years. I’ve run into a problem I can’t figure out. So I just bought a 1990 490D and all the electronics have been bypassed I didn’t do it I bought it like that. Engine runs great all dig functions work great so when I’m traveling it all works fine unless I put the left track to the floor it stalls the right track completely almost like it’s engaging the break somehow or something. They both track fine as long as I don’t put the left one full throttle. I haven’t had much time to dig In cause of work. I’ve downloaded the manual trying to decide where to start any input on what to look for or where to start troubleshooting is appreciated. If I pick the track off the ground they both track correctly as far as cycle time according to the manual so that gives me hope that it’s not a final drive problem. I found in the manual that it says if the break grabs inspect the counterbalance valve spool but it gives no location of that valve on the scamatic or anything that I seen. I was not impressed with the manual at all.This forum has saved me many times I’m hoping it will do it again.

 

[Vetech63]

Our resident Deere experts are going to want your machine serial # to gain proper tech info. Post that serial number and those guys will respond soon.

 

[mg2361]

Welcome to HEF jchand4!

Will it kill the right track in one direction, or both directions? When the right track stops, does reversing the right lever change anything?

 

[jchand4]

It kills it in both directions. I ran it a little yesterday after work to try to get some more symptoms. It has extra trouble going uphill both tracks get slow on a hill. It seemed to get slightly better if I would move a function on the right joystick while tracking uphill. It wasn’t night and day difference but it would unload the motor and track more smoothly when doin that uphill. Also it tracks like it’s supposed to when it cold. Took it uphill right after cranking it and it did fine but once it warms up it starts having issues.

 

[jchand4]

My serial #5015545

I couldn’t find it on the machine so I got it off the bill of sale so not sure how accurate it is.

 

[mg2361]

When your issue occurs, and with the levers at full travel and right side stalled, does moving a function on the right controller (Boom, Bucket) then allow the right track to start moving?

One too many numbers for the serial. Serial plate should be on the right side front corner of the cab.

 

[jchand4]

Yeah it did free it up especially when I first move the right joystick. I’ll see if I can’t find the serial number again when I get home from work this evening. Thanks for the help

 

[jchand4]

Alright so I found the serial number it’s ck490ds015545. Also I took the back covers off the back final drives and both of them have been replaced with hitachi drives I’m not sure if that’s a big deal or not I read that they were compatible. I plan on resealing the swivel soon im gonna do a case drain test once I get it back together. I’m trying to decide weather to dig into the propel relief valve or if it’s something in the main control valve but it confuses me how the left track that can affect the right The only connection I can see is the propel valve but I would think that that would affect both drives equally??

 

[mg2361]

both of them have been replaced with hitachi drives

The 490D is a Hitachi. The only difference from the orange Hitachi is the engine. Lets hope @LACHAU chimes in. He is the resident Hitachi expert.

The only connection I can see is the propel valve

Rotary manifold is a common connection.

When I get some time I'll peruse the schematic to see if anything jogs my aging memory.