Hot air

[sagnoff]

When I'm driving my new big block over 20 MPH or so, I get a steady flow of hot air under the dash. Lokking, I see an access hole under the dash on the right hand side where the instrament cables pass thru the firewall. The hole is wide open w/o insulation. Have any of you had the same problem? I guess trying to stuff the hole with insulation would be the easy fix.

 

[tigernut]

Yes, I have the same problem. Haven't investigated why as of yet. I did remove most of the insulation under the dash (it was falling down and a mess) during my interior restore. I haven't ordered replacement insulation yet.

Doug

 

[JohnZ]

You're missing the 2-hole rubber grommet that's made specifically for that speedo/tach cable hole application; all the resto parts houses have it.

 

[sagnoff]

It would be great if it was that easy! Is the whole about 2"or so?

 

[WayneC]

#16A on this page:
http://www.licorvette.com/pdfcatalogfiles/cat22/37.pdf

 

[sagnoff]

Thanks. On order!

 

[67HEAVEN]

It would be great if it was that easy! Is the whole about 2" or so?

Yes, that's it. There are two in the same area. The larger of the two sits in that hole and is parallel to the firewall. The smaller one is just to the left of the larger hole and sits 90 degrees to the firewall.

 

[sagnoff]

Thanks. Got the plug in and it really helps till the car heats up. Now I can feel heat coming from under the steering column. May be the clearnance holes for the brake and clutch pedals. Are their gaskets, seals, or bellows normally installed on these? I realize that because of the big block their will be a certain amount of amibient heat, I just don't want it blowing. Maybe I sahould move to maine??

 

[Ken Anderson]

You need to get an assembly manual so you can order all the seals you need. There shold be no air blowing thru the firewall, unless you're in Maine.

 

[JohnZ]

There's a black foam seal (that's probably missing or deteriorated) around the column on the engine side of the firewall, captured behind the bracket that attaches with two bolts. If you have manual brakes, the master cylinder seals its hole; with power brakes, there's a seal on the back of the booster that covers it.

 

[sagnoff]

I'm also going to check that clutch rod and brake boots are installed. How accessible is the steering seal w/BB? Can I use a silicone sealant from the dash side if I can't get to it?

 

[IH2LOSE]

with power brakes, there's a seal on the back of the booster that covers it.


This is the problem I had with my car the seal was missing around the booster .

Also are the vents closed.(not just that the cable handels are pushed in) Is the heat off.if you take the time you can find all the little leaks that bring in hot air.

But theres not much you can do to eliminate the mean radent heat that comes off the motor short of insulating the entire firewall and floor with an r19 insulation witch is just not practicle.