TECH TIP Technical Index

Getting Floored

by Mike C. -

Floor Pan Replacement Ė II

If you didnít break off any rusty bolts while taking everything apart, you are indeed a blessed individual. If you are those usual few that leave pieces of bolts in their holes because the head snapped off, donít fret. A gas welding torch with an easy hand will help get them loose, along with the properly-sized easy-outs.

Before I get started on further events, I should add that it would be a lot easier if you removed the seats. Anything you see that would only make the job easier by reducing the height you have to lift the body, remove it. If the engine is already out, much the easier for you. If not, itís still not that bad. Also, donít forget to remove any of the steering components that connect between the steering column and the chassis.

Now stand back and investigate the situation.

  1. If you have a standard Beetle with the torsion beam front end, youíre in business. If you have a Super Beetle, youíll have to support the chassis frame with some concrete blocks or jack stands, as there is nothing to support the front wheels once the body is removed. If you work on Super Beetles a lot, you might want to make you a spreader bar to connect between the strut towers and a brace that attaches to the middle of the spreader bar, extending down and tying it to the center tunnel. That way, the front wheels could then support the chassis.
  2. Remove all carpet, padding, pedal cluster, anything pertaining to the rear seat.
  3. If the heater cable tubes arenít separated from the floor pan, go ahead and do that now using the air chisel. Try your best to save the tubes. If they arenít salvageable, you can use brake line that is the same diameter of the original tubes. Just cut it and bend it to shape. Bundle up all the heater cables and tie them aside.
  4. Assuming that you have everything out of the way in the floor, get out the air chisel. Look at the welds on the floor pan perimeters. You will see that the factory spot-welded the pans to the center tunnel and at each end. Start at the back with the air chisel and slowly work your way around the tunnel, peeling the pan up as you go. Be careful, as the chisel will go through the thick tunnel flange if you let it. Trust me, youíll really appreciate the air chisel once you use it for this. The spot-welds are 3 or 4 inches apart, so there will be several to go through. Also be careful not to hit the brake lines, as they are attached right along the tunnel on either side.
  5. When you have the pans off both sides, you will have nothing less than a big mess on the floor of the garage and one picked-over chassis. Clean up the floor around you and take the old pans outside to the garbage.
  6. Now you need to prepare the new pans for the install. Make sure the tunnel is relatively free of slag from the original welds by taking a die grinder and grinding them down smooth. Take some coarse sandpaper and scuff the paint off the edges of the new floor pans so the welding will be easier.
  7. Test-fit the new pans for fit. Some years back, it was a chore to fit new pans. Nowadays with the full-length pans and better quality, this is not as big a problem. Note that a new rear bulkhead support may be included on the new pans. If your originals are rusted badly, youíll need the new ones. If not, chisel the new ones off the new pans and that will be less trouble to fit the new pans.
  8. The only way I know to truly make sure that the pans are on correctly, is to tack-weld them to a few spots around the tunnel (just enough to hold them in place and easily be taken off with little damage if need be). Then, set the body on the chassis to see if the bolt holes line up. Bolt hole alignment shouldnít be much of a problem, even if you donít do this. But just use your judgement here. In both of my floor pan experiences, Iíve had good results just by making sure the pans fit the tunnel well. You may have to trim the floor pan flange with some snips to get it to fit right. Be careful here and take your time. You can cut more off, but you canít easily add more back on.
  9. Once you know you have the fit correct, clamp or weight the pans down with concrete blocks or something else heavy to make sure the flange is flat on the tunnel flange.
  10. Make spot welds with the MIG welder the same distance apart as original, about 3 to 4 inches. Start at one end and go all the way around. Again, be careful about those brake lines!
  11. When you have everything welded down around the perimeters, weld your heat cable tubes back in the original locations. Itís easy to burn through the tube, so go easy on this weld.
  12. Unless you plan to make a smooth custom ride out of your Bug, donít forget to weld on the jacking reinforcements. These usually have to be purchased separately of the pans. The procedure is simple here, just locate them the same as the originals and weld them on, noting how the factory welded them.
  13. Okay, those pans are looking good by now. Clean any slag off the welds and take the seam sealer and brush it into the perimeters well. Since this will keep the water out of the seams and away from you, donít leave any gaps here. Brush the sealer both on the inside and outside.
  14. Scuff the outside of the pans down with a Scotchbrite pad and clean them off. Spray the entire underneath with the Rust Oleum black, undercoating, or other material/color of your choice. Donít trust the factory-applied paint to protect the pans. This is just there to keep them from flash-rusting during shipment. It is simply not very durable. Once the Rust Oleum dries fully, you canít easily scratch it, and it will look good for many years to come.

Next month Iíll finish up with re-assembly and other details. Take a picture of your project, enlarge it, hang it on a wall, show it to your buds while grilling those bratwurst chickens.

Your VW maniac & tech specialist,
Mike C.