Bonnet allignment
I wasn't sure where this post belonged, "Technical Question" or "Concours", so I decided to put it in concours. There is a discussion on another forum regarding bonnet allignment. Something came to light that I had not heard of before.
"When they came from the factory, they had a piece of felt placed between the hood
skin and the rear brace. This was most likely to stop rattle and
rubbing, but it also crowned the hood in the center and thus making it a
little smaller from side to side."
I have never seen this piece of felt. Can anyone else confirm this practice?
tags
Disclaimer - I don't own a TR2-3 so I'm certainly not an expert. But, here's a tidbit of information regarding the TR4. In July of 1962 Triumph issued a service bulletin on the subject of vibration and noise in TR-4's. Among the steps to be taken was the following -
"Firmly pack with felt or any type of suitable material between the hood and its front and lengthwise bracing frames particularly the left front section." This suggests several things, such as:
1.) It could be present or absent based upon the complaints of the owner, especially during the first year of TR4 production.
2.) It was procured locally by the dealer, so type of material, color, length and placement could vary. Notice the lack of TR part numbers ( or standardized specifications) and the emphasis on the left front support member.
I have read the posting on the other forum you mentioned and I noticed that two of the responders mentioned different materials, lengths and colors of the material. This fits the situation one would expect if the cure for the TR4 vibration was carried over from the TR3 cure. So, although purely speculation on my part, I'm throwing this suggestion out for comment.
Unrelated, but interesting, is that the same service bulletin also suggested that the rear transmission mount be changed for the Vanguard unit and dealers were encouraged to stock both parts in their supply.
gary
Gary: Thanks. I now realize that this must have been a common practice. My TR250 even has remnants of some felt, protruding from the brace - of course it's now a bright BRG color!
So does my XK150, but it's not BRG...:)
The packing was put into the hoods of the sidecurtain cars, at least the early ones, before the hoods were painted. If this becomes lost or eroded, the hood could very well rattle or drum, usually at idle. Perhaps that's the only time you notice it on account of road noise etc.
So, one way to determine original colour is to carefully dissect the felt!
If you can pull it off - pun intended.
-jdwtrxk
Oh my!!!
Stopping rattles is probably why the rivets were added to the rear of the bonnet's on the smallmouth 3's, firmly attaching the skin to the brace.
Mark
The rivets were on the front of the aluminum bonnets as well; at least somebody recognized the need for support between the brace and the sheet metal right from the start. Then again, aluminum being aluminum...
I realize this thread ended a year ago, however I have a question about the two rivets in the bonnet. Do the steel bonnets ever have rivets to attach the rear of the top skin to the cross brace and clamp the sound dampening felt?. Of course this is in the pre-flanged style. My 57 seems to be factory spot welded, but at the Portland Oregon 2011 ABFM I looked at a car with small bolts installed by the owner to simulate rivets. There was a TR2 next to it that had original rivets (don't know if the bonnet was steel or aluminum). This is a very small point, true enough, wish it was close to the biggest issue I have.....so I'm just wondering.
https://picasaweb.google.com/111096749895539854197/ABFMPortland2011#
se the 9th and 10th photo....
thanks
