I am close to bolting up the firewall to the body of my 22 Coupe. Any suggestions as to what goes between the two? Sealant,felt
Mike, I was warned to avoid using silicone as it makes it very difficult to remove the firewall at a later date if needed. I used a flexible mastic called Sicaflex, can't remember which one of their products it was. Further, I only used it across the top of the cowl, not down the sides.
Just for your consideration.
Allan from down under.
RV seam tape. Goes on after you bolt everything up.
Ford used felt on the steel firewalls. I don't know what they used on the wood firewalls.
When my dad replaced the original firewall on his 1917 touring back in 1950, he said there was a rubber gasket at the top of the cowl. He used a piece of inner tube when he replaced the firewall.
He was never satisfied with the quality of the replacement that he made, so in 2010 he replaced it again. He used an original 1917 firewall as well as the factory drawing to produce an accurate firewall.
We used foam weather stripping to create a new gasket around the outside perimeter of the firewall, and installed two additional strips at the top. Refer to the photo below.
Thanks to everyone. I went to the "Can't find any help" box store. I came out with a 10' pc. of soft rubber,about 3/4" wide and 1/8" thick with a peel off sticky back.The sticky back will hold itself in place until I can tighten the f/wall to the cowl,then it will crush nice and snug.At least thats what my brain told me.
Larry
According to the Parts and Price List, March 1 ,1920 ...'17-'20 wood firewalls used gaskets, rather sure they were felt.
P/N 3639 Dash weather strip, top (1)
P/N 3639B Dash weather strip, side (2)
The weather stripping we used above can be found at the hardware store or Home Depot, etc. It is foam rubber and has adhesive on one side. It comes in a variety of thicknesses and widths and can be easily compressed so it is very thin once the firewall is mounted and tightened down.
It is not expensive and you should be able to find it.
The brand we used is Dennis. The product is Heavy Density Foam Weather Strip, 1/4" thick, 3/8" wide in a 17 foot long roll. It is closed cell PVC.
http://www.wjdennis-rcr.com/Products/Weatherstripping/FoamTapes.aspx
Here is a comparable product from Home Depot that is 3/8" wide by 3/16" thick:
http://www.homedepot.com/h_d1/N-5yc1v/R-100197882/h_d2/ProductDisplay?catalogId= 10053&langId=-1&keyword=3%2F8+foam+weather+strip&storeId=10051#.UCqdTRxGG7s
Sounds like you bought the same thing except 3/4" wide instead of 3/8" wide.
Dan and Larry:
I'll ask my dad whether or not the original gaskets were felt or rubber. When we were working on the project, I thought he had mentioned that there was a rubber gasket when he removed the dashboard back in 1950.
If they were felt, it's possible that some type of sealer or adhesive was also used - maybe shellac - or they were impregnated with something that made them hard and led my to dad believe they were rubber.
My unrestored '17 has its original dashboard which has never been removed. However, I have no reason to remove it to see what is between the cowl and the firewall.
I suppose the best thing to do would be to actually look up the drawing for the gaskets.
If originals were felt,wouldn't they soak up rainwater? Rubber was certainly around at the time
There wasn't anything from factory on the '15-'16 cars, but if the customers complained the dealers were instructed to put some felt or rubber there in a march 24, 1915 letter from Ford: http://mtfca.com/encyclo/doc15.htm
Here is a factory photo showing the felt strip on the metal firewalls. The felt would be somewhat helpful to reduce running water at the body line. Most likely the felt was really just an anti-squeak
Compressed wool felt probably makes a good seal. I think it would allow for a tighter fit than a rubber gasket.
Who knows, maybe they also used some type of caulk or other sealant?
Somehow, I wound up with a NOS felt. I've used it for patterns many times. One thing I learned is, when placing the holes for the rivets, don't use a punch. Use an awl, otherwise the felt will fall through the rivets!
Larry, Are you referencing the lacing that sits on top of a metal firewall when you mention "rivets"? The wood f/wall as you know, gets bolted to the cowl on the pre 23 bodies.