Flapper Box Flaps

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David Austin
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Flapper Box Flaps

#1 Post by David Austin »

I have seen that these flapper box flaps would have originally had rubbers that create a complete seal and obviously reduce air escaping.
Replacing them looks like quite a challenge.
In your experience is this possible?
If it is, is it worth it?
Thanks as always.
David
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Jim Liberty
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Re: Flapper Box Flaps

#2 Post by Jim Liberty »

David, I have never seen rubbers on these. Guys ??? Chime in. ........Jim.
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Al Zim
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Re: Flapper Box Flaps

#3 Post by Al Zim »

YES if you had the seals in place it would work better! HOW DO YOU DO THAT? Take it off the pivot and remove the pivot and replace the seal? I do not believe I have ever seen that done. You have the shut off valve on the body of the car to prevent hot air leakage..that should be enough. Experience has shown that very few people need heaters these cars are not driven in the REAL winter. Not California, Texas or South Florida. Outline a program of service/restoration that will restore and improve the car. Do it in small steps and do it slowly! Zim
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Jim Liberty
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Re: Flapper Box Flaps

#4 Post by Jim Liberty »

I stand corrected Al. And not the first time either. ..................Jim.
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Martin Benade
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Re: Flapper Box Flaps

#5 Post by Martin Benade »

Some people make a pair of u-shaped rubber pieces to glue into the valves without taking it apart.
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Dick Weiss
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Re: Flapper Box Flaps

#6 Post by Dick Weiss »

I make the U-shaped seals from thin neoprene stock, pry the metal edges apart enough to allow the seal's edges
to be retained when clamping the metal back together.
I forgot to mention that I add a little adhesive sealant when inserting the strips. I saved many flapper boxes
over the years----IF the rest of the boxes are restorable.

Dave Erickson
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Re: Flapper Box Flaps

#7 Post by Dave Erickson »

You can grind the spot welds off then drive the shaft out of the flap and insert new rubber u-shaped pieces made from silicone rubber (not neoprene, which is only rated for 200 deg. F). When the flapper is removed you can braze 6mm washers on each side of the outlet tube to restore the pivot holes, which wear oval.

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Harlan Halsey
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Re: Flapper Box Flaps

#8 Post by Harlan Halsey »

David Austin wrote: Tue Nov 22, 2022 4:25 pm If it is, is it worth it?
When I lived in Boston I did not want the heat to melt the snow I tracked into the car. Now I live in California and I don't connect the heater.
So no, I don't think it is worth it.

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Jim Clement
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Re: Flapper Box Flaps

#9 Post by Jim Clement »

There is a Resto Strip or simmilar article in one of the registry publications. It details out the proceedure, I just do not know how to find it
 

Dick Weiss
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Re: Flapper Box Flaps

#10 Post by Dick Weiss »

Dave,

Either material will work as the flapper boxes don't get that hot w/all the cooling air passing thru them.

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Bruce Smith
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Re: Flapper Box Flaps

#11 Post by Bruce Smith »

Al Zim wrote: Tue Nov 22, 2022 4:44 pm Experience has shown that very few people need heaters these cars are not driven in the REAL winter.
Disagree completely, Al. We use heaters in the coupe a cabriolet often, as do most folks in the northeast. Spring and fall, we usually have the heater going at some point during a drive. We don't drive the Spyder except on warm days, because it hasn't got any heat.
Bruce Smith

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Bill Lawless
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Re: Flapper Box Flaps

#12 Post by Bill Lawless »

I also drive mine in 20-30 degree days, and the heat works awesome... Just a way to extent the 356 driving season!!!
 Thanks,
Bill
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