Flapper Box Flaps

356 Porsche-related discussions and questions.
Post Reply
Message
Author
David Austin
356 Fan
Posts: 109
Joined: Wed Aug 15, 2018 1:55 pm
Location: United Kingdom

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
Attachments
IMG_0154.jpeg
IMG_0153.jpeg

User avatar
Jim Liberty
356 Registry Member
Posts: 4086
Joined: Tue May 06, 2008 3:47 pm
Tag: Jim
Location: Orange Co., CA
Contact:

Re: Flapper Box Flaps

#2 Post by Jim Liberty »

David, I have never seen rubbers on these. Guys ??? Chime in. ........Jim.
Jim Liberty

User avatar
Al Zim
Registry Trustee
Posts: 3411
Joined: Fri Mar 14, 2008 9:14 pm
Location: FT.WORTH/DALLAS TEXAS

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
www.allzim.com 
356 Parts and Services

User avatar
Jim Liberty
356 Registry Member
Posts: 4086
Joined: Tue May 06, 2008 3:47 pm
Tag: Jim
Location: Orange Co., CA
Contact:

Re: Flapper Box Flaps

#4 Post by Jim Liberty »

I stand corrected Al. And not the first time either. ..................Jim.
Jim Liberty

User avatar
Martin Benade
356 Fan
Posts: 9483
Joined: Wed Nov 23, 2011 10:52 am
Location: Cleveland, Ohio

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.
Cleveland Ohio
62 Cabriolet
56 VW
02 IS 300
04 Sienna

Dick Weiss
356 Fan
Posts: 4057
Joined: Sun Apr 20, 2008 12:54 am

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.

DaveErickson
356 Fan
Posts: 1454
Joined: Sat Oct 26, 2013 9:34 pm
Location: Monterey, CA

Re: Flapper Box Flaps

#7 Post by DaveErickson »

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.

User avatar
Harlan Halsey
356 Fan
Posts: 1732
Joined: Fri Mar 02, 2012 2:05 pm
Location: No Cal SF Peninsula

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.

User avatar
Jim Clement
356 Fan
Posts: 1131
Joined: Tue Oct 26, 2010 10:46 am
Tag: 1957 356 A Coupe
Location: Calgary Alberta

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
356 Fan
Posts: 4057
Joined: Sun Apr 20, 2008 12:54 am

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.

User avatar
Bruce Smith
356 Fan
Posts: 1357
Joined: Sun Jun 19, 2011 9:47 am
Location: Rochester, NY
Contact:

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

User avatar
Bill Lawless
356 Fan
Posts: 829
Joined: Mon Oct 25, 2010 10:17 pm
Location: Northern Vermont

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
65' 356 SC Cab Irish Green :D
82' SC Targa
81 VW Westfalia with 2015 Forester Engine
BMW 64'-R50/2, 75'-BMW R90/6, 74' BMW R90/6, 81'-BMW R65, 02'-K1200RS

Post Reply