My son's 98 S10 has a wierd wiper problem. When you first start the truck the wipers work OK. After 20-30 minutes the wipers stop working. It sounds like something is overheating but I'm not sure what. Any suggestions?

Bad circuit board in wiper motor. Wiggle the electrical connection on the wiper motor, if they start up, you can replace just the board.

There is a recall on just this problem. From GM its called a campain.

I will have a look on Alldata and see if I can find the number for you.
Had it done on my 97 took em about 30 mins and cost $0.00 :O

Here is a couple of the major ones for the Blazers

Wiper Motor - http://www.tc.gc.ca/roadsafety/recalls/recall_e.asp?recno=10539&;
Seatbelt - http://www.tc.gc.ca/roadsafety/recalls/recall_e.asp?recno=10665&;
Rearview Mirror Short Circuit - http://www.tc.gc.ca/roadsafety/recalls/recall_e.asp?recno=10513&;

1998
Rear Axle Fracture - http://www.tc.gc.ca/roadsafety/recalls/recall_e.asp?recno=6942&;

Hope this helps
The Fixes mentioned here are free of charge to have fixed.

Macgyver

Bad circuit board in wiper motor. Wiggle the electrical connection on the wiper motor, if they start up, you can replace just the board.

Instead of replacing you can just solder the 7 points that connect the board to the black plug. Doesn't cost you anything and fixes the problem.