My Webasto Aquahot was not operating correctly, blowing fuses, and the motor was making grinding noises.

I removed the Webasto and installed a new bearing set (about$40) PN 378313. The set consists 12 components - bearings,washers, spacer, and nut. The impeller to motor carrier needs about .003 clearance or tighten the nut, back off 1/4 turn and confirm impeller turns freely. If not, back off another 1/8 turn and so on.

My Aquahot appears to work fine now.

When I ordered parts, the dealer said that changing this bearing set is a little unusual. However, they had a number of reoccuring problems on Webasto units, with numerous components changed (including the electronic control unit) trying to correct various problems. They ended-up repairing these by changing the bearing set. I do not think, nor do I have anywhere near enough experience to say this is a silver bullet. But, it was an interesting comment from a repair facility with much experience.

Ed Roelle 5.19.2006

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