So I take my 1st passenger in the 70.
Just a quick run into town in the dark. Now before I kinda, thought that maybe, just a little I could smell antifreeze in the corkpit but the head gaskets  seep just ever so slightly so I just "overlooked" it.

Getting on the freeway we take off like a rocket. I slam that LT-1 into 2 gear and we are going over 60. Lovin it.

Then it gets ugly. Big smell of antifreeze. Window fogs up to the point I can barley see. Even wiping the window every 30 seconds with the defrost off and the windows down we are almost driving blind. My friend Matt has antifreeze all over his foot. (Man I am glad it wasnt the wife!).I know its the heater core.

Now for the questions.
How hard is it to get up in there to replace that bad boy?

If I decide to have it done at a shop can I take the hose running from the water pump and put it to the motor so I am by- passing the heater core and not filling the corkpit with more fluid?
 
One should not overlook the ever so slight smell of antifreeze.

Yes, you can bypass the core. I have never replaced one myself but have read posts from several members who have done it. If it is an A/C car it is certainly more difficult. It appears one needs a truck load of patience to accomplish the repair.

Scott

oh my gosh john you are making me feel bad and look bad too, I am so sorry to hear about the heater core, I never, honestly,  had any signs of it being in need of repair.  Please let me know tje cost of the new battery so I can refund you that and let me know about the heater as well maybe I can slip you an extra hundred to help out. lets talk some time late next week.
Larry

Replacing a heater core is a bit of a pain, but only because yuo need to twist and reach in odd ways.  Most books tell you  that you need to remove the inside heater box, but I never do.  Just remove the under hood box, push the inner box in far enough to let you get at the bolts holding the core in place, and wiggle and jiggle until you get it out.  Jiggle in the opposite direction to reassemble.

And of course Scott was right about bypassing or plugging the heater hoses.  An emergency fix is to clamp a vice grip over each hose, squeezing it shut.

And remember, no matter what problems you might have, it is still a red LT1 Corvette.

Larry

See I didnt know you could get to it from the engine side. I'll take a look at that but this maybe one of them deals I dont fix myself.

Too often I break other things while at the same time fixing things.

Now Larry, do I think for a second that you decided to sell the car because the heater core was about to let go? No I dont.

It does explain that whiff of steam that came out the defrost during the test drive.
I dont hold you responsible for the things that go wrong. But I will also leave it up to you as to your comfort level. I aint trying to make ya look bad, I just need advice as to how hard a job this is and where to go from here.

You will have full access once you pull the passenger side dash panel and the center dash section loose, assuming you do not have A/C. Once my 69 sprung a leak and had it apart and found that the local auto parts store no longer have acces to the cores for a 69 non - A/C car - only Ecklers and Mid America to my research and based on their prices I decided to splurge and bought the Vintage Air setup instead. Now I have heat and A/C plus a flat fire wall - no more bulge - makes getting at that last header bolt a lot easier 

Check out this thread (Replacing Heater Core).  It's an oldie but a goodie!  In it is a reply from Juliet where she included a link to some pictures she took of the task.

Hay John, Zip & Corvette Magazine have alot of Tech articles online for that kind of repair & more. www.corvettemagazine.com Down on the right under POPULAR ARTICLES "Heater Core and Box Rebuild" that should help you.Aaron19762009-02-26 13:47:01

Funny thing... my 75 heater core is out.  I have factory air.. I am in the process of replacing all with Vintage Air.  It has been a task so far.  I would have farmed this job out if I knew what I know now.  I was also in the process of pulling the speedo and tach when I discovered the leak on the heater core box .  So now I have the whole dash out once again.. lesson learned I should have replaced it all when I was restoring the car.  But as the story goes money was tight now I back doing what I should of done to start.  Have fun.

Phil sorry to hear that.
I did farm out the heater core as with my skills I most likely would do more damage than good.
They wanted to have the original recored instead of a replacement. I guess the holes all line up kind of deal.

I am glad to hear you caught the leak BEFORE the passenger in your Vette got his feet full of antifreeze.

Good luck!
jt's732009-02-26 18:24:11