Polaris runs but won't vaccuum

[aylad]

Looked at the troubleshooting guide suggested on next page of forum (under "Polaris won't climb walls anymore") but it doesn't offer no-vacuuming tips. The polaris runs but will not suck anything into the bag. I notced this morning that the head float is cracked. Does anybody know if the function of the float head has any bearing on vacuuming ability or does anyone have other ideas? This Polaris is a several years old. Thanks for any ideas.

Edit: Loooked at the manual again. Does "won't back-up" mean won't vacuum or won't go backwards?

Won't back up means that you don't get the squirt of water out of the backup valve that actually picks the unit up and re-places it into the pool. I don't think the head float has anything to do with the vaccuuming ability--at least when mine was cracked it still would vaccuum. Is it running too fast over the debris, or is it trying to lean over and run on its side?

Janet