HI Robban
Hard to tell when google will next spider your site but if its down more than once when Googlebot comes calling you can expect the visits to become less frequent.
I would be gone the next morning if my webhost was down more than an hour.
Godaddy has had problems with Google in the past, and my advice would be to run not walk to a good solid web host who can offer you hosting with a dedicated IP address and support where you see results in minutes not hours.
Good hosting is not expensive, but it can be hard to know who are good hosts and who are not.
You might want to look at
http://www.findmyhosting.com/ if you do want to consider a new host. This site offers impartial reviews of hundreds of hosting companies and allows users to rank those hosts and comment on their performance.