Cowl - Top Inner rust repair

[bpilati]

Part #66310-E4600 is where the air intake for the HVAC fan is located. The fan is bolted to the underside of this cowl over the intake opening. This intake is a sheetmetal rounded rectangular duct with a flange that is welded to the cowl. I have rust around the flange of this intake that is allowing water to leak onto the passenger floor area. This intake is covered by a shroud on the Cowl - Top outer (66300-E4600) that keeps rain from entering this intake. It appears to me the only way to access this intake from the top of the cowl, is to cut out the shroud so that the rust hole can be treated and sealed. Has anyone else had rust issue here? If so, how did you attack this?

It appears that they tried to apply a thick bead of sealer/caulking around the this intake (at the factory?) to keep water away from the flange. I used a video boroscope to look under the shroud but it was very difficult to see the rust because of the limited maneuvering of the camera under the shroud. Before I start cutting around on this sheetmetal, I wanted to get some thoughts from you guys.

Edited February 20, 2013 by bpilati

[Lassekongo]

Hi This is how I did it, but I hade to fix rust in the engine bay wall to so it was easier this way for me.

Hope this will be of some help.

Lars

[bpilati]

Haha, thanks. I don't think I'm in the same ballpark. But that is some nice work there.

[doradox]

I cut mine out. Cut out a rectangle and welded in a patch. Then re-cut the opening in the patch and welded in the replacement I made from underneath. Getting seam sealer all all the way around the bottom flange was a pain. Had to get creative with some tubing and mirrors to see what I was doing. I'm not so good at stopping and taking pics so this is about all I have.

[bpilati]

How did you fabricate the new intake duct?

[doradox]

How did you fabricate the new intake duct?

I cut out a rectangle of sheet steel and bent it over a tube to form the basic shape. I overlapped the ends a little and welded it closed with a few tacks on the outside and inside. The carefully bent down the flanges along the straight edges with some wide billed pliers. In the corners I hammered out the flanges against a block of wood. It's functional but not "restoration" correct. But who's going to ever see it?

Steve

[bpilati]

Painting it afterwards is going to be a trick too.

[bartsscooterservice]

This makes me wanna check mine ! Sometimes it scares me...the rust

[bpilati]

That might be wise.

[doradox]

Painting it afterwards is going to be a trick too.

It was. Fabricated a foam brush with a wire handle to get the spots I couldn't get to. Sometimes I think it might have been easier to completely disassemble the entire unibody. Or go to CA and get a relatively rust free car. I actually enjoy doing the work though so it's more the journey than the destination for me. Another spot to consider (is there any NOT to consider on a Z?) .

Steve

[bpilati]

I've put about $10K in the paint and body, and mine was rust free compared to yours.

[bpilati]

Here's what I found yesterday after removing the black rubber compound that apparently filled this area with at the factory. There is another smaller hole at the other end of this crevice. Looks like removal of the air intake duct in this photo will be part of the solution. This hole is actually a bit larger than it appears here. Once I started scraping around there was more rotted area.