490E Excavator slow turning

[swangerenterprises]

I have a Deere 490E excavator with 10400 hours on it. The machine turns fine when sitting on the flat or going down hill, but is very hard to turn on any kind of up hill grade. Also if you try to spin one track forward and one backwards they do not spin very fast. Another issue is that when tracking straight line the right side all but stops occasionally. If you just periodically let off the stick a little it doesn't seem to do it. I have already rebuilt the rotary manifold and that made a big difference on turning on the flat and changing between travel speeds. It switches through travel speeds just fine. I have only used the machine about 5 hours since i have owned it for several months. Before I bought it, the machine was through a Deere shop and had all of the pump pressures checked (I was told) and i believe the DP sensor replaced. If you put the bucket against something and track it seems to have good track power (doesn't bog or slow down). I talked to a gentleman who has a sales/repair shop and he told me that the 490Es had weak drive motors from factory and never turned well. The machine has 27.5" pads if that makes a difference. Just looking for some things to check. i have only ran newer cat equipment and dont have experience with Deere. Thanks

 

[swangerenterprises]

I should add then when you try to turn on the hill it’s like both tracks just stop but it doesn’t seem to bog the machine. Like I said if sitting on the flat it turns fine side to side one lever at a time

 

[mg2361]

Welcome to HEF swanger! If all your other functions work as they should then the only thing to check would be travel crossover relief pressures. Maybe even check pilot pressure to the travel spool caps to make sure the spools are being moved all the way. Deere/Hitachi excavators however are very weak travel machines as a whole.

 

[swangerenterprises]

Where would I check the crossover pressure? I see on the parts schematic that there is some valve blocks under the machine relevance to under the seat. I was going to pull the propel solenoid and check it and the spool?

 

[mg2361]

You will need to acquire manuals (Operation and Test manual TM1504). Too much to explain here.

 

[John C.]

I haven't had to fix one of these machines but in general the travel motor circuit reliefs cartridges are in the travel motors themselves. To check the pressures, you plumb gauges into the outlet of the pumps, block the track from turning and then run the travel over relief. Travel pressures on most excavators are higher that the rest of functions.
If you have never done this type of work, the books will help. There are dangers involved and it would be better to have someone there to show you what is involved and what to avoid to stay safe.

 

[swangerenterprises]

Thanks for the replies. I have a friend with probably 40 years experience working on heavy equipment I will see if he can give me a hand. Thanks