Gap between the hood's rear seal and cowl

[Mark E.]

There's a 5/16" air gap between the hood's rear seal and cowl with the hood closed on my 1970. I'm chasing down sources of hot cockpit air, and believe this is a major contributor. What's the best way to fix this?

The photos below are taken with the camera at the base of the windshield, pointing towards the front of the car with the hood closed. The wiper door and cowl grille are removed. The rear edge of the green hood can be seen at the top. The tip of the rule is resting on the cowl's surface for the seal, and the bottom of the seal is at about the 5/16" mark- the width of the gap.

The hood fit is virtually perfect and flush with the cowl grille panel behind it (or at least as perfect as fiberglass panels fit on these cars).

I believe the seal is original; I've owned the car since '90 and it looked old then. It's 1/2" thick.

To fix this by replacing the seal, it would need to be 5/16" (gap width) + 1/2" (current seal width) = 13/16" thick. Are new seals that thick?

Other ideas?

Hood Seal Gap.jpgHood Seal Gap Measured.jpg

[Mark E.]

Re: Gap between the hood's rear seal and cowl

Argh. Two days ago, I used the "contact us" form for three parts vendors who sell this seal asking for its thickness (really its height), but no replies yet.

Does anyone know the proper height the hood seal? That will help me decide if a new seal will solve the gap problem. I'd like the Forum's input before talking with vendors.

[Mike F.]

Re: Gap between the hood's rear seal and cowl

My 70 seal is around 9/16". IMG_3228.jpg

[Mark E.]

Re: Gap between the hood's rear seal and cowl

My 70 seal is around 9/16".

Thanks Mike. That's about the same height as my seal. Does it make a tight seal against the cowl when the hood is closed?

[Mike F.]

Re: Gap between the hood's rear seal and cowl

Thanks Mike. That's about the same height as my seal. Does it make a tight seal against the cowl when the hood is closed?

I'll have to remove the cowl grille and see. I'm up in Argyle, feel free to stop over anytime.

[Mark E.]

Re: Gap between the hood's rear seal and cowl

I'll have to remove the cowl grille and see. I'm up in Argyle, feel free to stop over anytime.

Instead of removing stuff, try some silly putty, or a peeled ripe banana to measure the gap.

On my hood, the sections of seal at the corners of the hood snug up nicely to the cowl, but at the center I have to gently press down on the hood to get the seal on the cowl. Which means I may have the same problem if I just install a taller seal. So I'm not sure what to do.

I'm taking time with this is because I believe this is a source of hot air into the passenger compartment.

Thanks for the invitation. Are you attending the Judging School in Grapevine this weekend? I'm in group 2.

[Bill C.]

Re: Gap between the hood's rear seal and cowl

mark --

A/C 454 cars will get hot air in the car almost always.
I chased heat for three years on my old 72 454 car.

it ended up being two items:
1. the plenum air door (vac actuated ) in the wiper bay was not working and by default it would stay open always. the VAC dashpod was shot.
2. when the factory bonded the front clip on, the bonding cement slipped and the plenum on the PASS side of the car had a gap.
when you shined a flashlight up in the plenum (from inside the car kick panel area) you could see the light coming through from under the fender (by the AC evaporator).


and just in general -
the damn cars run hot as crud anyways

I have seen folks put a heater hose cut-off valve in. it was manual and during the summer you can cut the water to the heater core and buddy it will keep the temps REAL COOL in the car.

Also -
AC cars did not have functional Astro ventilation (rear plenum was bonded shut). So when you have your windows open, it will suck air from any hole it can find around the firewall area.
my steering column would so hot after about 45 minutes of driving on the HWY with my windows open.
it was literally sucking superheated air in through the steering column.

fyi..
the 69 435 coupe I had pulled zero hot air up the steering column with the windows open. difference, IMHO the astro vents working.


it was a really bad design. they should have made the AC are with functional rear vents.

hope this all helps some.
Bill