Ok, so a couple things going on, but they're common mistakes that people make, especially early on (and sometimes later!).
The primary problem is that your object is scaled to gigantic proportions. Select all objects (A) and scale them down (S) to .05. Move everything so that your Zamboni is back in the center of the grid and resting on the grid, just for (optional, just for aesthetics and to keep a reference point).
:edit: I forgot the 2nd part. Though the above will solve your view problem, it would be a good idea to select your Zamboni after you've got it all scaled down, and press Ctrl + A which will apply the current scale as the objects default scale.
In blender there are essentially two scales for a mesh.
First, you have it's size according to the mesh (the actual geometry). But when you're not in edit mode, but in object mode (when you press Tab you are toggling between the two modes) and you scale the object, the mesh size, according to Blender, is staying the same. But the object size is getting bigger. A bit tough to understand, maybe, but think of it like this:
You have a cube in blender that is 2 foot x 2 foot x 2 foot.
You decide to scale it up 2x by going into edit mode, selecting all the vertices, and scaling them up 2x. Blender now sees your cube as 4'x4'x4'.
But lets say instead you take your 2'x 2'x 2' box and and scale it up in object mode by 5x. Blender doesn't actually see a 10'x10'x10' box. It sees it as the original 2'x2'x2' box multiplied by 5. So essentially like this (2'x2'x2')x5.
This is important for many simulation type things, but it can cause problems when your object is so extremely large that Blender doesn't quite know how to display it.
So going back up to the Ctrl+A command and applying the scale, your telling Blender that the size that the object is, is the size that you want to be the default 1x scale.
Taking the cube example I made above, if you scale a cube up 5x in object mode, giving you the (2')x5 cube, then press Ctrl+A Blender now sees your cube as a 10'x10'x10' cube.
I hope this is clear, let me know if I can clarify anything for you.