I have a 2007 Cat 420E. The ride control seemed to stop working every now and then a week ago. I was thinking it may be a loose connection in the wiring somewhere. I did read a thread on HEF about a solenoid/valve. It got me thinking that may be the problem. Can anyone tell me how to properly troubleshoot/safely replace these. Any experience with this type of problem is greatly appreciated. It's not like I'm on down time because of it, it just saves a lot of clean up when I'm shuttling material over pavement regularly. Not to mention, it's easier on my back too! Thanx Jamie.
ride control sounds like you are on the right track. I've only just joined the forum, so not sure of how much detail is needed or what you are fully after, I will read on, and if you want a reply later on I will try and help you out. Things such as checking resistance of the solenoid, power from the ecm to the solenoid, check terminal connections corrosion. I always tend to look at wiring looms that are in the line of fire from objects and movement ect that can get damaged.
I should of asked whether your machine has the Auto-function, which is controlled by the ground speed,, does the ride control kick in when you have the bucket raised and the switch on? Machine does not need to be moving.
I have a three way switch. Auto(on after 3mph), Off, and On. The light on the switch indicates that it is functioning in both on and auto. It doesn't work in either auto or on. I have only checked from looking up from underneath the machine. Next I think I will take up the floor to see if I can find a bad connection from there. I want to spray oil under the floor panel anyway and make sure the road salt hasn't corroded anything. It was the first snow plow season it has seen. Not enough cake sitting around for 3 watermain/sewer breaks all winter. This is the third Cat backhoe I've had with ride control and the first time I've ever had the ride control fail. It is kind of new to me as far as really getting to know how it's plumbed and wired. I don't want to do the wrong thing and cause "self inflicted down time" Thank you for taking your time with my little quest for knowledge:drinkup
Check and see if you have continuity at your ride control solenoid, also if you have access to the electrical schematic, check and see if that solenoid is normally open or normally closed.
I might be out of line with this response, and all do respect to the Cat operators here. Where I work we have a case 821 Loader. The ride control. (which I think, makes the operator lazy) but that is a different subject...takes hyd fluid from your raise cylinder and drops whatever load you are holding right to the ground! I have stepped into this machine and had this happen in some very difficult situations. Hopefully Case has got this error under control before someone is killed!!!
ride control The ride control circuit is like any other cat loader. The ride control valve opens up the piston end pressured oil in the lift cylinders to the ride control accumulators which dampen the load of the bucket while travelling, thus giving a smoother ride, stops loader from bunny hopping across the yard and increases production and driver comfort. Since your ride control seems to not work at all I would check the resistance of the ride control solenoid, if that is ok, then you need to get the correct tooling and check the ride control cylinder nitrogen pressure. Note High pressure warnings on the cylinders
Thanks Chris, I'll do that. Any idea what the resistance should be? I'm assuming that the solenoid is usually open. I'll browse through the CD to see if there is any schematics on it. I doubt there is. Cat will keep that secret until they come out with a G series. I don't think there is a problem with the nitrogen pressure because of the way the problem started out intermittently. If it was a problem with the pressure I would have expected it to fade away gradually or suddenly be gone, depending on what type of leak. Ride control doesn't make us "lazy", It makes us "spoiled"
A lot of times, it says the resistance on the schematic.
larger solenoids are usually 12ohms, med 25ohms, 30ohms, they usually aren't much greater than that. You will know if the solenoid is no good if it has a high resistant or a dead short, over load the multimeter