The heater channel is the foundation of the VW Beetle body.
It runs from the front chassis support...
...to the rear chassis support.
The floorpan bolts to the bottom of it. So replacing it is no small task. The spot welds on the bottom of the rear quarter panel need to be located by removing the paint.
Then they can be drilled out.
Then the same on the lower edge of the front inner wheel well.
On the inside the lower side of the inner panel of the rear quarter panel must be drilled. When drilling the welds against the rear chassis support a special spot weld drill should be used the preserve the metal beneath. This tool is like a small hole saw.
It is helpful to either weld or bolt a metal brace in the door opening to maintain the correct measurements for the door once the door post are cut loose.
The post are welded solid to the channel and are best cut with a cut off wheel on a die grinder.
A Dremmel© tool works well in the tight places.
Remember that the neater you can make the cut the easier it will be to weld later. There are some welds on the outsides of the chassis supports that are a little hard to find but they will become more obvious as you lift the body to remove the channel. In one of our previous tech articles you learned how to remove the body. Unbolt the body but leave the bolts loose in the supports in the inner wheel wheel.
The body can pivot on these. Since the body only needs to be lifted enough to remove the channel it can be lifted from the inside. With some boards and a little bit of ingenuity you can lift the body with a small jack under the dashboard.
A sharp chisel may be need to free up some of the welds.
Finally the channel can be separated from the car.
Now after a little cleaning up of the edges and some of the welds you can put the new channel back into the body.
Ease the body back down making sure that everything is going back into place and fitting up.
Tack the door post in place first and check for fit.
The width should be correct if you braced the door but you may need to use a jack and a board under one of the door post to give it the right shape.
Once the door fits in just right weld up the rest of the channel and bolt the body back down. The Super Beetle channel welds flush against the front chassis support while the bottom plate extends under it and is welded solid along the edge.
The convertible has several extra support panels on the inside that must be drilled and removed before you can get to the heater channel.
The convertible also has a support rail that is welded to the bottom of the channel before it is put back in.
As you can see some skills in welding and fabrication are need to do this job but it can be done. I would strongly recommend that you watch us do this job from start to finish on Vol.7 of our Bug Me Video series before you try to tackle it. You will be glad you did.