I disassembled mine for cleaning.
You can find the schematics here for example :
http://www.vacshopusa.com/eureka_4870dt.htm
I didn't know about the schematics before I took mine apart, they would have been helpful.
I must caution you that the base assembly (where the roller brush, the height adjuster, the hardwood/carpet switch etc. are housed) is tricky to take apart.
I am having a hard time putting it back together.
You should be very careful with the idler switch assembly (the hardwood/carpet switch). If the springs there come loose/apart you may have a hard time putting it back together as I am.
Also, take pictures as you go along disassembling the more complex parts. I know, I didn't and am having a hard time putting back the idler switch assembly.
If you read thus far and found this information useful, I am glad that you did.
If you do decide to take the base assembly apart, please do share a picture or two of the idler switch assembly with me. Seeing the fully assembled part would help me put mine back together.
Vishal, September 2009
