SAAC Forum

The Cars => 1968 Shelby GT350/500/500KR => Topic started by: Corey Bowcutt on January 20, 2022, 08:28:07 AM

Title: Heater Hose Replacement
Post by: Corey Bowcutt on January 20, 2022, 08:28:07 AM
I am currently reinstalling my rebuilt motor into my 68 GT350.  I did a complete refresh on the engine compartment while the motor was out being rebuilt but I did not replace the heater hoses.  In hooking up the heater hoses I feel like they are too short to rout the way they should and they are not the stock hose with red stripes.  So I am feeling like I have gone this far and should replace these hoses.  The console and seats are currently out of the car.  So just how hard is it to replace these hoses?  Are there things I should know before/while tackling this task?  Any tips or advise is appreciated.

Also I see NPD has concourse hoses supplied by Marti Auto Works.  Are these the best ones and is this the best place to purchase them?

Thank you,

Corey
Title: Re: Heater Hose Replacement
Post by: Royce Peterson on January 20, 2022, 10:34:51 AM
No big deal to replace them. If the car has no AC then remove the glove box and reach over the top of the heater to loosen the hose clamps. Then cut the hoses lengthwise to make them easier to remove.
Title: Re: Heater Hose Replacement
Post by: Corey Bowcutt on January 20, 2022, 10:49:35 AM
I do not have A/C. So you do not have to remove the heater box?
Title: Re: Heater Hose Replacement
Post by: CharlesTurner on January 20, 2022, 11:14:31 AM
It is easier to just remove the heater box in my opinion.  If the core hasn't been replaced, or the foam seals, good time to take care of that.
Title: Re: Heater Hose Replacement
Post by: Bob Gaines on January 20, 2022, 11:16:01 AM
Quote from: CharlesTurner on January 20, 2022, 11:14:31 AM
It is easier to just remove the heater box in my opinion.  If the core hasn't been replaced, or the foam seals, good time to take care of that.
+1
Title: Re: Heater Hose Replacement
Post by: JWH on January 20, 2022, 12:04:08 PM
Quote from: CharlesTurner on January 20, 2022, 11:14:31 AM
It is easier to just remove the heater box in my opinion.  If the core hasn't been replaced, or the foam seals, good time to take care of that.

+2!

Note that there is a long screw that attaches a bracket on the heater to the under-dash. It is easy to miss this screw and tug hard on the box and break off part of the box. Looking from the floor up under the dash, this screw and bracket are just above the vent door.

When reinstalling the box, I like to connect the hoses and clamps to the new heater core first. Position the box on the floor under the dash. Feed the two hoses through the firewall from inside the car. Have someone under the hood pull the hoses through the firewall while you lift the box up into place. This prevents the hoses from folding over and kinking between the box and the firewall. The hoses will want to kink every time and you can't see it. Once the box is up in place and the four studs are through the firewall, attach the nuts to the studs and re-attach the bracket to the under dash. Make sure the wires from the motor have been pulled through the firewall also before tightening the nuts.

Last thought is the original cardboard plenums that lead off the box to the two defroster vent hoses are getting hard to find and seem to be in demand. If you have your original cardboard plenum and defroster vent hoses, treat gently.

Be patient, go slow and good luck with the project.
Jeff

Title: Re: Heater Hose Replacement
Post by: Royce Peterson on January 20, 2022, 12:08:46 PM
No reason to remove the heater box if you simply slice the heater hose after moving the clamps forward. That's a big job doing it that way!
Title: Re: Heater Hose Replacement
Post by: CharlesTurner on January 20, 2022, 01:14:26 PM
Quote from: Royce Peterson on January 20, 2022, 12:08:46 PM
No reason to remove the heater box if you simply slice the heater hose after moving the clamps forward. That's a big job doing it that way!

I've done it before and it is a 2-person job that way and will tear up the firewall pad doing it, plus it also risks breaking the solder on the heater core fittings.  Not to mention lots of swearing and skint up knuckles!

4 nuts on the engine bay side, unplug the heater motor wires, disconnect the cables and the long screw up top and the box pulls right out. 
Title: Re: Heater Hose Replacement
Post by: 68gtcoupe on January 20, 2022, 01:35:24 PM
Quote from: CharlesTurner on January 20, 2022, 01:14:26 PM
Quote from: Royce Peterson on January 20, 2022, 12:08:46 PM
No reason to remove the heater box if you simply slice the heater hose after moving the clamps forward. That's a big job doing it that way!

I've done it before and it is a 2-person job that way and will tear up the firewall pad doing it, plus it also risks breaking the solder on the heater core fittings.  Not to mention lots of swearing and skint up knuckles!

4 nuts on the engine bay side, unplug the heater motor wires, disconnect the cables and the long screw up top and the box pulls right out.

I did this job 7 years ago on my 1968 GT coupe, non-A/C car.  I agree with Charles' assessment.  I had a helper and the job went smoothly.  I replaced the heater core, heater box, blower motor and hoses all at the same time.  No issues whatsoever since then.

Terry
Title: Re: Heater Hose Replacement
Post by: Corey Bowcutt on January 20, 2022, 02:27:44 PM
Thank you all for your feedback.  It is all very helpful.

Corey