I looked in the J37 publication and it lists the “felt”. It doesn’t provide any guidance on how the felt is attached to either the guard or the bonnet (adhesive?), nor does it provide any information on dimensional characteristics of the stuff.
So, anyone know…how wide this felt seal is…how it is attached to the stone-guard or is it attached to the bonnet using adhesive? Thickness has to be around 1/2" if my car is anything to go by.
I don’t think it requires any glue at all. I might have dabbed a few spots of glue to hold it to the edge of the guard for installation, but once it’s in place and has screws passing through it, it’s not going anywhere. I’d have to check it for thickness. It’s either 1/8 or maybe 1/4. Ultimately I think it’s only there to act as a buffer to keep the thing from rattling.
Half inch thickness is right, Les, and they’re held onto the stone guard with split rivets:
The top of the stone guard features seven holes. The split rivets are pushed through the felt at the hole locations in the stone guard and then spread apart:
Incidentally, there are four other shorter felt seals in the bonnet. These are hidden away at the tops of the two air ducts (aka valences) and are held in place by two split rivets each:
I think these shorter felts are about 1/4" thick.
Ha wow I had no idea. I guess I’ll lose more points for lack of rivets!
Most often the “correct” way of assembly is also the cheapest, quickest and easiest, which makes sense from a production line perspective. Sir William was always in search of efficiencies. You could use screws and achieve the same result, but it would take longer and cost a few pennies more.
I’ve never understood the value of that piece of felt. The stone guard doesn’t contact the bonnet nor is it likely too given the gap between the top and that it is secured to the bonnet itself. There is no necessity to prevent air from passing between the top of the stone guard and bonnet. One might argue that having it in place helps direct air through the stone guard and thus, through the radiator, but the radiator foam piece already does that.
Years ago a noted E-type restorer and owner judging my car at a concours suggested a piece of thinner felt weatherstrip readily available at Home depot. I stuck it on for looks, figuring if it’s good enough for him it’s good enough for me. .
Maybe just an aesthetic, John, but considering those four other felt seals between the inside of the bonnet centre panel and the valences, which are completely hidden, that reason seems unlikely, as is any other assembly line activity that has no function. It’s there for a reason, though it might not be obvious. I’m wondering if the earlier cars lacked the felt seal and it was added in an attempt to address a deficiency that manifested itself after those first several hundred thousand miles of real world experience. I suspect a belt and suspenders rationale to maximise airflow through the rad when cooling issues from that tiny bonnet air intake (yet another significant improvement of the S2 v. S1, along with the twin cooling fan) became an issue.
FWIW - I see no fasteners on my S2, nor the holes for them:
If this changed at some point then Les probably needs to know which side of that change his S1½ falls on.
Most likely the fold over rivets were on the very early cars that also used other pieces of felt under the bonnet. They got away from felt and went to a bonding compound as felt held moisture. I do not recall seeing the rivets on the later cars. BTW: George, you shield surround needs some paint!!!
My car has the holes for, I assume, some kind of fixing device. I understand these are special rivets. There are 6 holes in the top of the frame, 2 for each flat area one at each end of the curved section.
That’s “patina,” and should bring an extra grand, on eBait.
No screws passing through it Erica, nothing to screw into, unless you use sheet metal screws and put then in from the top into the frame??
Thanks Nick, just what I needed.
Just fyi Dick, Nicks car is also a '68, you consider these “later cars”?
I seem to recall some dialogue from way back when on the merits or not of this seal. The conclusion, I think, was that it does assist the cooling in the manner you mentioned John, it helps provide maximum airflow through the radiator. I also understand your point about the seal on the radiator really doing the same thing…perhaps the felt on the stone-guard is just that, a guard against foreign objects getting past the grid.
Most anything after 1962 is later in this case. I do have the rivets and will include 6 in the package
Phone
Clip of the stoneguard on my '68 just before tearing apart about 4 years ago…
Could be you’ve just discovered a very obscure feature of the 1968 model year, Les. Someone once told me (George Camp, I think) there were 8 or 9 pages of changes noted for 1968. The Series 1.5 isn’t rare, but the cars made on any given day of production will be different from those that rolled of the line previously.
We should henceforth refer to the Les Halls stoneguard variant.
then there is always the question, "Is the stoneguard original to the car?
