That could be a clogged water pump, or loose belt. I had the same probelms with mine. If it is an older model, take the front panel off, its usually two screws, and the water pump should be on the side with a rubber belt attached. disconnect the two hoses via clamps. Look at the pump, there should be a spindle contained within. check to see if it is clogged or see if the "teeth" on the spindle are damaged or the belt could be loose or damaged. Also check for dry rot on your hoses.
xavier
December 2005