s2 1971 heater box. The flap obviously stops air going through the heater core when shut. When its open and heater tap off I assume we get the fan blowing cold air into the car. My flap will shut off the air to the heater core when pushed the other way the flap does not seal the hole at the bottom of the heater box. I assume this would mean air flow into the car would be insufficient. Is this problem hard to resolve. It clicks open and will click shut but leaves a gap of 10mm around internal flap. Box is out of the car.
@jory Hey Geoff Nice to see another Aussie working on these cars. This is a really useful site, full of knowledge and tips. Just don’t mention our spiders or snakes as they get a bit worried.
Cheers
Jacko
The flap mechanism is pretty simple - it’s mounted to a rod that penetrates both sides of the box. On one side is the cable to actuate it and on the other is a spring to create the tension. If it is not closing completely, check that the actuator cable is adjusted properly to allow the lever at that end to rotate all the way closed. Try disconnecting the cable first and see if the flap closes fully, then reinstall the cable in the closed location. It’s difficult to put into words but it’s a simple adjustment - like a brake lever on a bicycle.
The Series 2 heater box flap doesn’t have a spring to assist the closing of the flap against the bottom of the box as far as I’m aware - mine doesn’t for sure. It has a Heath-Robinson mechanism made up of levers and a spring on the inboard side of the box. The spring is supposed to apply pressure to close the flap firmly in either open or closed positions. Mine doesn’t work too well - it works best if you use vigorous movements of the lever when operating it - not a gentle smooth movement. Here’s a not very good photo of the mechanism on my box - some of the parts I had to fabricate myself as they were missing…
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In case no one has mentioned this, they’re supposed to be foam padding on the surface of the flap to make a seal. The foam turns to dust and disappears with time. The usuals sell a heater box rebuild kit.
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Thanks for correcting my understanding of this flap mechanism - I am not as familiar with Series 2 I admit.
The flap is supposed to close the hole at the bottom of the heater box. Can I just block this hole off permanently?
Only if you want air to blow into the cabin at all times. The function of the flap is to direct the air flow. Either to inside of the car, or block it from entering the cabin. When it closes the bottom opening, all air enters the cabin
I am thinking with the flap against the heater core no air can enter the cabin, when it is away from the heater core air will enter the cabin , hot or cold pending on heater tap. This being the case I could block off the lower hole which the flap does not quite block off, and everything should work ok. Am I missing something?
Yes. As already stated, if you block off the hole in the the bottom of the heater box, air from the snorkle will always pass through the heater core (heated or not) and into the cabin. Why not just fix the flap valve in the heater box and use it as designed?
The flap valve is very straight forward. I would keep it intact!. I upgraded the squirrel cage and motor and the air flow is impressive. Assuming the snorkel is sealing tight to the heater box to avoid engine/gas odors, it is going to make the cockpit temp much better. I thing a person should really get to know how the system works, as it is not intuitive. The British drive on the wrong side of the road as you know!
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Geoff;
I have several photos of the heater box in various stages of restoration. If I knew what you wanted to see I would be glad to post.
As far as it allowing ‘cold air’ to come into the car that will happen when cold air is available, as in your cold weather time of year.
Regards, Joel…
Ah but a billion plus Indians do too…… not to mention all of South Africa , Australia, all former British colonies, …… so we could have a debate …. But looking at Wikipedia is instructive on the history
I was told by an Indian friend that their roads are so crowded they can only drive on what’s left.
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I am proceeding to take the side off my heater box to adjust the flap movement. Is the flap axle braised at both ends? If so I will need to heat up and melt the braise, yes? Thanks everyone for there contributions
I had no ideer all billion of’em have driving licenses…
How did you go with your trip yesterday to Candy’s …. Any results ?
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Geoff;
The rod that operates the ‘flapper door’ has a fixed piece on the ‘inside end’ and a removable piece on the ‘outside end’, no need to melt anything.
Regards, Joel…
Hehe: if I go, it will be this coming Sunday!
I/she will report if it happens.
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Thanks Joel. That worked well. Cheers Geoff