Understanding and Improving the heater... Options

[Rod]

I have just replaced the heater blower and control panel on my 914 and the front trunk blower now works for the first time The previous owner to me covered over the dash vents with vinyl, so I have uncovered and trimmed around these too.

I have totally stripped out the interior, sorted any rust (er... none ) dynamatted the whole interior, put in extra soundproofing, fibreglassed over and repaired the back pad where the board/wood had perished and fitted a new grey loop carpet set from Appearance and Performance, phew. Looks fabulous and returning to perfect condition

Now as I understand it, the dashboard levers work like this...

1. Top lever

FRESH air vent and fan control

2. Middle Lever

Controls direction of FRESH air delivered by above lever (left footwell, right dashboard.)

3. Bottom Lever

Controls direction of HEAT from 4 below. (Again far left footwell, Right Dash vents)

4. Lever between seats

Controls rear fan and therefore HEAT into cabin.

So the front fan plays no part in heating the car whatsoever, just FRESH air.

HEAT is controlled directly by the lever between the seats (the direction of which is controlled by the 3rd land lowest lever on the control panel)

So, if I am correct with the above can you tell me why hot air only comes from the drivers side? It is really hot air on this side and blown with quite a force, yet the passenger side is cool.. I know there are differences between 73 and 74 cars in that the earlier cars (like mine) have a rear fan that only blows down the drivers side and later cars had a T piece which splits the air from the blower and connects to the passenger side, but is this why it is cold on the ps?? Surely it wasn't that bad from the factory in '73??

Long post sorry, but hopefully concise regarding my problem.. My wife is an Aussie and is complaining that she gets cold, so I'm determined to get more heat on her side if possible.

Cheers (IMG:style_emoticons/default/beerchug.gif)

[Joe Owensby]

You understand the system correctly. Note that there is air blown through the heat exchangers with our with the electric fan on. There is some air drawn from the engine cooling fan to do this. In addition to adding a "Y" and hose to the right side of the car as the newer cars have; you may check to make sure that your flapper valves on the heat exchangers are connected and are working correctly. This is the flapper valve that is located under the car- between the heat exchanger and the passenger compartment. Should be on on each side of the car. Each one has a hose that passes air into the hose that connects to the inner part of the rocker. There should also be a cable going to each flapper valve. These cables are connected to the center lever you described.

Often, these flapper valves malfunction, or are not connected at all. Also, the heat exchanger may have rusted. If so, it will allow most of the heating air to exit before it can go to the passenger compartment. If so, get a good pair of stainless steel heat exchangers to fix this.

JoeO