:( Grinding noise - Grandson's rear axle Haro BMX; took it apart and cleaned;can't get it back together again. :confused: Bike shop wants more than was paid for the bike to begin with. Anyone know where a diagram is showing how to put this thing back together?:D

Firstly, the bearings and cones need to be set in a certain way, otherwise it will grind even worse and the wheel will have to be scrapped. The most common problem is with the little spring loaded ratchets inside the freewheel hub. When the bearings fail, these get snapped off and grind on the bearing races and the hub is ruined.
Unless you know what you're doing, take it to a shop.
Haro's are top brand bikes and depending on how old the bike is, it may still have a warranty. Even if it doesn't fall under a warranty item, (I don't think it will), the shop you bought it from should try to take care of you if they are reputable.
I would also go to other shops in your area to see what prices to fix it will run you. Shop around, one may have an old wheel laying around that they could sell you on the cheap.
Hope this helps.

Bikes are expensive. If you ed it up, then pay the shop to fix it when u cant.

Did you take the axle out and remove the bearings to clean them? If so, when you put it back together you can't tighten it all up too much or it won't spin. You need to set the bearing cones first... just tight enough so the axle doesn't move up, down or in and out. Then you need to hold those in place while you tighten up the lock nuts... make any sense? Check out this diagram. Good luck and any bike shops could repair this for you for under $40.

http://www.bikewebsite.com/fthub.htm