Hey guys,

I've recently sanded and treated some minor rust underneath the cowl in the plenum area where the wiper motor etc. goes and i remember a while back seeing a Custom Z that had a solid cowl (e.g no air induction holes) and i was wondering since this area is prone to rust if it would be a good idea to fill in the holes of my cowl (at least on the driver side and leave the passenger side as is for the heater air intake.)

Would this cause the wiper motor to overheat? I'm trying to figure out why the holes are there other than to gather leaves and wet slush.(even though I've treated with POR I'm still paranoid). Looking for an opinion on this, is it is a bad idea?

Thanks,

Sam

If you insure your drains are good, you shouldn't have to worry excessively about rust under the cowl.

I was paranoid about water dribbling from the drain holes to exit inside the front fender, so I extended the exit holes with 90 degree plastic plumbing bends and some rubber tube the correct size.

It now exits at the bottom of the fender.

Brian.

I have wondered about the idea of making a very small 1/2" tall fiberglass dam hidden under the windshield side of the cowl to divert water to the sides instead of letting it run into the wiper motor area in addition to putting a water catcher tray right under the cowl air induction holes. Not sure the idea makes sense but it is an idea anyway.

Mike

would the defrost work properly if those vents were not there? Oh I just noticed you said except that side.

Edited June 26, 201212 yr by pjoe

the heatermsystem does get its fresh air from the cowl area. Could you draw air from inside the cabin instead?

Edited June 26, 201212 yr by TomoHawk

I remember someone saying they blocked the air vents in the cowl and still got air into the car okay, hopefully they might see this thread. With the fan on air should be drawn from around the cowl in other areas as there isn't an airtight seal between the cowl and the car body.