4 wheel drive not working

[RCDT30]

Just bought 2007 sportsman 800 twin. This is my first atv i dont have a clue what to do. My four wheel drive does not seem to be locking in how do i check it? I changed the front diff fluid had water in it but i still cant tell if it is locking in. I tryed jacking all for wheels off the ground to see if once the rear turned more than the front if it would lock in but it did not? Should i take it to my polaris dealer and have them just change all fluids and filters and check everything? They said it would be at lest $250 that seems really high but like i said this is all new to me any help would mean alot thanks.

[Russ C]

take plug in on top of front diff apart and see if ther is 12 volts to it with key on and awd swith on

[Bruce!]

Welcome to the board!

[lost cause]

make sure your switch is working and that you have 12v to the diff. Next drain your fluid and make sure you replace it with the Polaris fluid. You may have to do this a few times to get all the water/dirt out. These polaris diffs. can be finicky. If that still doesn't work then you will need to pull the front diff. apart and take a look at it. There is a plastic sprague cage in there that will crack and/or break. If it is cracked/broken you need to replace it. Most that ride mud replace it with the billet aluminum one from superatv. One last thing to look at is the armature plate. Sometimes the armature plate gets slightly warped and will cause issues with the 4wd being able to lock/unlock. The cage + the plate if done yourself will only set you back about $200.

[RCDT30]

Thanks for taking the time to answer my question it is a big help. Going to try what you said.