What size Bolt Thread ??

[fonz]

1963 series 3. What size are the BOLTS (thread and length) are the BOLTS that holds the Bumper "brackets" to the Car Frame ? Spent hours in the hardware store and they claim they are neither SAE Or Metric ! Thank You.

 

[Bill Blue]

They are 20 threads/inch. Can't remember for sure, but I'm thinking 7/16" diameter. If not 7/16", then 1/2", still 20 tpi.

There are no Metric fasteners on an Alpine. The vast majority are SAE "fine".

Bill

 

[DanR]

Fonz, The factory original bolts for the SIV -SV Alpines I have are 1/2-20 x 1 and 3/4" long

 

[Fordtootsie]

Bill I am working on my ser I using ser V seats. The screws that hold on the lever to move the seat back and the screws that hold the spring mec on the other side of the seat are - metric

John

 

[Barry]

Bill I am working on my ser I using ser V seats. The screws that hold on the lever to move the seat back and the screws that hold the spring mec on the other side of the seat are - metric

John

First I have heard about a Series Alpine leaving the factory with metric fasteners.

 

[Fordtootsie]

These metric screws are the dickens to get out. They - or at least mine - were rested in place and required heat and everything else to remove. I dont like them because as a screw they use the threads as a bearing surface. There are three per seat.

I replace mine with a screw that has a shank to act as the bearing surface.

Here is a picture of their screw and the one I used. I had to get a long screw in order to get a long shank portion for the bearing surface.

 

[Glenn]

My series II have SAE bolts fastening the seats to the floor.

 

[tylerite3124]

These metric screws are the dickens to get out. They - or at least mine - were rested in place and required heat and everything else to remove. I dont like them because as a screw they use the threads as a bearing surface. There are three per seat.

I replace mine with a screw that has a shank to act as the bearing surface.

Here is a picture of their screw and the one I used. I had to get a long screw in order to get a long shank portion for the bearing surface.

Any metric fastener you find on an Alpine or Tiger would have been put there by a PO, not ROOTES. Best to remove and replace it with the correct fastener. I have even had a custom body shop tell me the fasteners in my car are Metric but when shown they fit an SAE thread gauge they just scratch their head. I don't go there anymore.
Rick

 

[Alpine 1789]

I have seen metric bolts used to 'fix' captured bolts or threads that were stripped and vice-versa. Find a bolt just slightly larger than the original, retap and Bob's your uncle. Of course, I have also seen them forced into the original nut, which 'fixes' the problem and saddles the next owner with a lot more work.

 

[DanR]

I found during my first V6 conversion the use of standard bolts in a metric thread. 3/8 20 were utilized by jose for the 10mm 1.5 threads for the headers. Probably more easily found. They "fit" but were slightly loose fitting, easily striped. It took me some time to find a good 10mm for the headers.