WeasleVette454

I thought my problem was going to be solved by reflective insulation but heat transfer (is convection the word?) from the engine compartment doesn't seem to be the problem. While driving, hot air comes out of the heater duct, but the blower motor ISN'T running. My feet are ROASTING!

A friend suggested bypassing the heater core but I think that's not the best fix for this. Any input???

Weasle

mooneyd

You can by-pass the heater core using valves, that way you can open them in the colder weather for heat and close in summer to keep hot water from running through the heater. There are a lot of guys out there with this setup.
Good luck!

Super Stock

You can get two quick opening valves(Home Depot etc.)whatever sizes you need, four threaded nipples(like those in h2o pump/intake)and four hose clamps. Cut the hoses and install. You may have to cut a little section out. I went ahead and sandblasted the brass valves and painted them black so they aren't as noticable, cut most of the handles off , and installed mine down low near the firewall. They just basically lay on the frame. Thave held up for quite a few years and are closed most of the time . I do open them from time to time just to circulate fresh coolant thru them.

Stewart's74

Sounds like your heater box needs a new seal kit.

flynhi

Install valves on both heater hoses. Pull back carpet and insulation under the steering column and pedals. Have a friend wave a shop light under the car while you look for light leaks from above. Plug all leaks. reinstall carpet.

Install heat delector panels from a 69.

A very small hole will admit a large amount of heat when the temp in the area of the exhaust manifold is 600 to 800 degrees.

mayberg

Before you spend too much time chasing the heater box solution potential, check out vettfixr's tech tip:
https://www.corvetteforum.com/techti...=241&TopicID=3

I did this - the difference was like night and day. Cheap and easy. I'm pondering hooking up my heater core now.

checklst

That artical stop 99% of all heat roasting my feet!!!!!!!! I will NOT BE INSTALLING THE SHUT OFF VALVE NOW it's not needed


[Modified by checklst, 8:15 PM 6/29/2004]


[Modified by checklst, 8:16 PM 6/29/2004]

Super Stock

I only installed manual block valves in case my 31yr. old heater core gave up a long way from home so I could just block it off and keep going.

adam

Someone mentioned that a gap where the heater core pipes go into the heater
box causes heat (seemingly like when the bypass is not working.)

Thus I am wondering if using expanding foam to seal around the pipes
would be advised, given the heat of the coolant? I know that some of the
expanding foam canisters put out highly flammable cured foam.

Nick-75Roadster

Hi! I'm a new registered user to the Forum, but I've been reading/following for a while now.

As far as the heat problem, I've had this on a 69 convertible and a 76 coupe in the past. I've pulled up the carpeting, added insulation, by-passed the heater core, plugged openings behind the dash... not much help! I've got the feeling that Stewart is right about a seal kit for the heater box, though. One thing I used to do to cope with the heat was set the heater control to DEF (left the fan in the off position). This directed the heat to the defogger vent and kept my feet cool! You never noticed the heat there, especially with the top/windows down. This is only a band-aid until you fix the problem, but it will keep you from roasting.

vettfixr

Thanks mayberg. I was just going to jump in here and give a link to it. I just bought a book that discusses corvette tech tips and the obvious question about cabin heat was addressed. It amazed me that no one else has found this fix because it wasn't addressed in the answer. Maybe I should send it to Corvette Fever or Vette magazine and spread the word.

WeasleVette454

VETTFIXR...........

I will most definitely do this. I am in the middle of seat restoration (they look great so far) so i am halfway to the problem. We have our town festival in two weeks so I wanted to have the car ready for the cruise in / car show.

I'll report my progress upon job completeion.

Weasle

Bobchad

I've got some additional information, how the system works, etc. at my web site.
http://home.comcast.net/~chadwick.ro...entilation.htm

vettery

If your hood seal is good at the rear and you've got hot air movement then yep, that's your problem. The fender bonds to the outer edges of the firewall there. That bond and the rubber seal at the back of the hood are the largest things preventing hot engine compartment air from entering the fresh air plenum and proceeding into cockpit. :mad

87bob

I had a similar problem with the wifes 79 The door in the cowl area was stuck open allowing hot engine compartment air to come through the HVAC ducts.