Heater Backdate on a '78sc

[DaddyGlenn]

I noticed my engine compartment heater blower motor housing was loose, so I began to disassemble it so I could return the fasteners to their proper position. That is when I discovered a burned section of the board that holds the motor brushes. A light touch to the bush on that side and the board gave way. So much for reinstalling that fan motor.



So now I am contemplating a heater backdate. Although it might be a tad bit cheaper to purchase a replacement motor, I kinda like the idea reducing the clutter in the engine compartment.

For those who have completed this project, I have a few questions.

Without having the blowers up front, does not having the blower in the back really make that big of a difference?

and a technical question... Removing the blower mounting bracket also removes three mounting points for other items. What do you do with the stuff that is mounted in the three spots pictured below?

[kodioneill]

I have a heater blower motor from a backdate if you decide to go that direction. I have plenty of heat in my sc with the back date. The valve on the bottom circle is a vacuum control for the WUR warm up cycle. the others are fuel lines that you can tie strap out of the way. I just finished a back date on a 77s if you want I can send/post some photos of the bracket modification.

[will hung]

Glenn, I only have heat because I need defrosters in the mornings and evenings. When I originally backdated my heat, I still had my stock heat exchangers and I had no issues with lack of heat. The blower motor basically helps keep a steady supply of heat when the engine speeds are low (basically at idle). Now with my SSI's, I can't leave the heater levels pulled all the way up because you'll start sweating.

As far as your 3 connections highlighted above. The 2 fuel line bundles weren't hung off of anything on my car, so I didn't have to deal with them. The lower guy with the 2 vacuum hoses going into it and 1 coming out I did have to deal with. I disconnected it, drilled a bigger hole into it, and placed it over one of the intake studs left from removing the blower motor, and I hold it down with a nut.

[kerthunk]

Are you running SSIs or the stock exhaust? The SSIs generate quite a bit of heat.

Without the blowers, the main difference that you will notice is that the volume of heater air is purely dependent upon engine rpm since the engine fan it the only thing pushing the hot air into the cabin. So, when the car is still warming up and you come to the long light and are idling there for a while, it may get a little chilly. Some folks have said that it has a negative impact to the windshield defroster, but I haven't had any issues with that.

When I pulled that bracket out, I reamed out the hole for the thermotime switch (at the bottom) and mounted it to one of the studs (frontmost one). I got another clamp for the lines going to the WUR that I mounted to the other post. I let the other fuel lines fly free.

[will hung]

I just realized I have a pic here at work. You can just make out the shiny new nut in this pic.



I have a couple pics at home highlighting the difference it makes as far as reduction of clutter goes. It's pretty shocking. Makes servicing the engine so much easier.

[BlueWing]

Short answer for your question. For the fuel lines I just bought an insulated clamp much like what is used elsewhere on the car with a mount hole that fit the stud and on the vacuum switch I bent it to a 90 degree and I don't remember if I needed to open the mount hole to fit the stud but here is a pic.




Terry

[Brown747]

Glenn,
Backdated the heat in my 78 last year in an effort to de clutter my engine bay. More than enough heat out of this setup with SSI's. Cleaning things up I also shaved the fan bracket mounting pads on intake runners #2 and 3 and I moved the thermo valve behind #3 and used a spacer and a bolt to mount it to the throttle linkage pad. There are 2 tapped but unused holes in that pad that will accept an 8mm bolt. Mount it high enough to clear the throttle bellcrank. I replaced the injector line clamps with black zip ties.
HTH Thor