Can anyone tell me what thread type is used and what are the most common sizes are on the Model T
All are SAE and most are fine thread. There's a chart floating around here with most listed. It is a bit small for these old eyes to read,but other than that ok.
5/16"-24 UNF is probably the most common, with 3/8"-24 UNF a close second. The head bolts are 7/16"-14 UNC and the spindle bolts are 1/2"-20 UNF. All threads on the T are right hand, I believe.
There are a few oddball threads no longer used, like #14-28 found on the flywheel and the bendix cover holddown screws.
I was given a set of Model T taps and dies by some Model T friends a few years ago.
This is the list that came with them.
1/4-24 Bendix cap & mag brass screws
5/16-24 general bolts
3/8 24 Rod and wrist pins bolts.
3/8-16 Some engine block & wheel rim bolts
7/16-14 head stud
7/16-20 tie rod & spring shackles
1/2-20 king pin, main bearing bolts, head light.
9/16-18 steering arm, radius rod, rear spring bracket, camshaft
5/8-18 rear axle
11/16-16 rear spring perch
3/4-14 differential plug,late- square wrench hole
3/4-16 front axle -right and left hand thread.
3/4-24 diff plug early, hex head, pan drain plug
13/16-16 Camshaft -timing gear nut
1-7/8-16 exhaust manifold
1/8-27 pipe oil petcock
13/32-16 tail spoo; -tap
2-1/8-24 wheel hub and hub cap.
Well, I believe we were both wrong. Bendix cover and mag brass screws are #14-24 which is far closer to 1/4"-24 than #14-28 so I was way off.
Thanks Peter for your list.
Take a look at the following web site:
On the left column is a "Technical" link. Click that and then click the "Bolts - Nuts" link on the left. This brings up a document with pretty much all the bolts / nuts and other threaded parts on a Model T. If there is something that is different for a given year, that is also documented. Note that this is a work in progress so if you see something incorrect, please let me know.
The passenger spindle nut is RH thread, but this is hardly unique to the T.
The passenger's side spindle nut is LEFT hand thread, unless you've a rt. hand drive car.