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View Full Version : TR2/3/3A TR3 bolts 2 questions in one.



Kleykamp
04-26-2012, 11:22 AM
If I recall the fender bolts, among others, are 1/4 x 24? tpi. Any source for these beyond the big 3. What are the bolts that hold the original style, black air cleaners on. I don't even see them listed with the air cleaners in any catalog.

TR3driver
04-26-2012, 11:35 AM
Nope, 1/4-28 along with practically all the bolts that hold the body together.

Air cleaner bolts are 5/16NF (24 tpi)

martx-5
04-26-2012, 11:38 AM
The fender bolts would be 1/4"-28 with a 7/16" hex. They have pointed ends to make it easier for them to enter the caged nuts. I don't remember the length (about 1"), but I'll look up the part number and find out unless someone answers beforehand. I also don't remember the size of the air cleaner bolts offhand. Probably 1/4"-28 also.

You should be able to get these sizes at any hardware store or Home Depot if you don't have to have the pointed ends.

Arrow
04-26-2012, 12:30 PM
Triumph loved 1/4-28 bolts. Yes the body is mostly assembled with 1/4-28 pointed bolts. I elected to forego the pointed bolts and bought stainless steel as I have also elected not to paint the bolts and washers. You can buy 1/4-28 bolts from any fastener /bolt store a lot less expensively than buying from the big three. Remember stainless is great for holding things together but does not have the strength of a grade 5 or grade 8 bolt for high stress points.

luke44
04-26-2012, 01:39 PM
Nuts, bolts and fasteners can be a major time consumer with a good restoration. Almost all the fasteners on the TR are fine thread. These aren't as common at places like Depot, Lowes etc as coarse thread. My local Ace Hardware has an excellent selection of hardware, including fine thread and I'm guessing most small local hardware stores would do better than the big box stores. Problem is, more often than not, you end up with the stainless steel specialty stuff when you get into fine thread - (read - expensive). It's ok for a bolt or 2, but not a whole car.

Here's what to do:

#1 - buy a good bolt identifier gauge - you might spend $15.00 for it. You'll be amazed how often you use it. This (https://www.dvorakmachine.com/photos/thread_gauge.jpg) is the one I use - don't go for a cheapy that is a flat piece of steel with a bunch of holes punched in it.
#2 - go to Mcmaster.com (https://www.mcmaster.com/), go shopping, and get your account set up when you check out. Bookmark their site - you'll be back.
#3 - place an order for the more common fasteners to start - 1/4" x 28, 5/16" x 24, 3/8" x 24, and the flat and lock washers - watch your washer sizes - MC have all sorts of thicknesses and outer diameters (buy the washers in boxes of 100 - they're cheap). (also - btw - bolts are always identified by diameter and threads per inch, <span style="font-style: italic">not</span> by bolt head size). MC will deliver in small quantity, in a few days. They are excellent to do business with and prices are very good.

PS - maybe it's just me, but if I have original bolts in decent shape, I always try to save them. I bought a tumbler (https://photos.plaxo.com/photos/get/32/7/98/233/2683/86290-m-0.jpg) which gives excellent results (https://photos.plaxo.com/photos/get/32/7/98/233/2683/86291-m-0.jpg) in cleaning up old fasteners.

Hope this helps, good luck

PS - I would think the air cleaner bolts are 5/16, but that's without checking.

TR3driver
04-26-2012, 02:16 PM
Remember stainless is great for holding things together but does not have the strength of a grade 5 or grade 8 bolt for high stress points.

Stainless threads are also more prone to gall and seize than carbon steel. Regardless of which you use, adding a dab of good anti-seize (I prefer the copper based stuff myself) will help ensure it comes apart easily next time.

The original factory part numbers for common hardware will give you the relevant details. All common hardware items start with two letters (eg the HU0807 shown above), and can be found in the hardware catalog:
https://docs.google.com/open?id=0B2H2NJt34OffMjJhY2YwZmQtYzgxNC00ZTk0LTk1Y TUtZTIyZmU3ZTc1Y2M4

If you don't have a copy of the original factory parts catalogue, I recommend you get one. Reprints are available from TRF, or there is a PDF version you can download from https://docs.google.com/open?id=0B2H2NJt34OffMWQ4N2EzZGQtNjc0Ny00YmE2LWFiN 2UtZWYzMjNjNGFiYzY4

Some things that look like common hardware items will have 6 digit part numbers, which indicates that there is something special about them. Could be material, shank diameter, grip length, or head dimension, etc. As they are generally safety-related items, my suggestion is to buy them from Moss or TRF. (Personally, I don't trust VB to not sell common hardware in place of specialty items.) Sometimes they are even quite expensive (which generally indicates that the vendor had them custom-made to specification). Best example I can think of offhand are the brake caliper mounting bolts on a later TR6, which are hardened with precision metric shanks (to fit the metric calipers) but with SAE heads and threads (to fit the mounting bracket).

Also, watch out for screwball threads. They aren't all SAE! A few places use BA threads; and some are even oddball metric. It's particularly easy to mistake 2BA threads for 10-32 as they are almost the same (2BA is .185" by 31.75 tpi; 10-32 is .190" by 32 tpi).

sp53
04-26-2012, 05:55 PM
Hey kleykamp I would advise not throwing away your old bolts. The heads are embossed and people that are concourse enthusiast really like them.

mgbmedic
04-26-2012, 06:34 PM
hey Luke44, Does mcmaster have the 1/-28 flat head slotted bolts for the fender to trunk area. These are hard to find locally.

luke44
04-27-2012, 07:24 PM
I bought those from TRF, because they were an identical match, they were having one of those big sales, and I was ordering other stuff as well, so they rode freight free. I didn't measure, but you can probably get pretty darn close with Mcmaster by looking at their round head slotted machine screws. I didn't go measure a screw, I just guessed at 3/4".

When you find what you are looking for, be sure to click on the "cad" button to see a full size drawing with dimensions (https://www.mcmaster.com/#cadinlnord/90276a559/=halhw9). This way you can check it exactly before you order.