• Hi Guest! Being a Paying Supporter is NOT a requirement to participate at BCF. However, subscribing will help ensure we can continue to serve the LBC community for years to come. If you enjoy BCF and find our forum a useful resource...Please consider supporting us by **Upgrading**
    (PS: Subscribers don't see this banner)

Basic E-Type Question: Fasteners - Metric or SAE or ...?


Freshman Member
As I mentioned in my introductory post, I’m probing around the edges of a 1970 Series II E-Type trying to ascertain the damage.

I replaced the gear shift knob recently and discovered that it had a 5/16” 18 threaded connection.

However, the seat fasteners seem to be:
  • Floor Mounts: 6mm x 1.25
  • Seat Position Assembly: 6mm x 0.9

I have a small assortment of metric taps and dies, but nothing with these thread counts.

Am I measuring this correctly?

As I dig into this project, will I be needing to build up a selection of non-metric taps and dies?

I want to clean up and salvage old fasteners, before making a bulk order to replace the most-damaged ones.

Answers to these questions will help me get the right mindset (and tool set) for this project. :rapture:


Luke Skywalker
I have restored 1969 and 1970 e types in the past and do not recall any metric. Be sure that someone previously hasn’t botched it.


Luke Skywalker
I believe the seat to floor fasteners are 7/16 NF. Always nice to have a book...I only purchase Bentley or factory editions.


Freshman Member
I believe the seat to floor fasteners are 7/16 NF.

My floor fasteners are M6 x 125. So, I'm thinking that the old ones rusted out and they refitted it with metric fasteners.

Always nice to have a book...I only purchase Bentley or factory editions.

I learned recently that Jaguar did not issue a comprehensive parts list for the E-Type Series II. So, the author researched all of the available information on that edition's parts and published this book.


Freshman Member
Mystery Solved!

These bolts were BSF and BSC threads. (Basically, fractional inches.)

Once I got a good fractional gauge, I was able to get the following measurements.
- Floor Mounts: 1/4” x 20
- Seat Position Assembly: 1/4” x 28 (Hard to find!)


Darth Vader
My DIY hardware store carries these bolts, seems they decided to go with the area and even bought a complete cabinet full of specialized gun screws.


Jedi Warrior
Bolts Bolts Bolts Standard Course and fine thread that's it But they do have grads see top of bolt 3 5 8 and marking are 3 blank 5 slashes 8 triangle replace with same grad. 3 we called butter bolts weak zero work load 5 for working load and torque load 8 strength head bolts one time use after torque. I use SS bolts where rust happens but not load seat frames mounting acc. under hood for looks. As for the nuts that can also apply but not much in cars. Bolts do two things tie things together torque things down nut hold bolts. The weakest point of a bolt threads so less threads the better say any front end parts. Fine thread bolts may have a different torque than course may also if in say block as to through bolting.

Metric different numbers thread count and head size UK did not go to Metric but early Wentworth say MG T's had same bolt threads bigger head size EU cars use Metric bolts with even number wrenches Jap odd number wrenches or the other way around. So to end many taps many wrenches mine are painted different colors. Madflyer


Jedi Knight
My 94 XJS had bot metric and SAE threaded fasteners.
While I was working at an Independent Jaguar, Bentley and Rolls Royce shop,
I took home every fastener that was going to the trash.
Now, I have a tool chest filled with spares and no vehicle for them.
Let me know if I can help out.
I need to supplement my SSI to survive.


Luke Skywalker
Geez, just read what I posted and it should have been 1/4 nsf not 7/16. That would be one large fastener of a seat!
I must read before posting.
glad you have a book now.


Darth Vader
Whitworth, British National Fine thread, or SAE. Use adjustable over metric. Wasn't metrics in the era of E-types. Once you round a bolt, it stays rounded.

Clive Wilkinson

Freshman Member
No metric fasteners on any E-Type.

Practically all the fasteners on an E-Type are Unified Series which is virtually the same as SAE, so they're mostly UNF or UNC.
Early E-Types have some BSW and BSF on items like the Moss box which were carried over from earlier models. There may also be some B.A. (British Association) for small screws on items like the carburettors and some older Lucas stuff.
Pipe threads are likely to be British rather than American NPT.
Similar threads
Thread starter Title Forum Replies Date
R GT6 Triumph GT6, basic work estimates Triumph 76
Talon TR2/3/3A Throttle rod link to carburetor; basic questions Triumph 4
Drone Dog Some Basic Overdrive Questions Austin Healey 8
JimLaney I need some basic restoration info for my first car project Restoration & Tools 20
JamesH Wedge new to me TR7, need some basic info. thanks. Triumph 2
J TR2/3/3A TR3 Guy '59 project Basic body work finished Triumph 5
M Some basic questions about Bugeye Spridgets 4
T TR2/3/3A TR3A Wire Wheels Basic Questions Triumph 23
W MGC Basic Information for locating identification numbers on MGC's or MGC-GT's MG 1
Tinkerman TR2/3/3A Basic Distributer cap Question Triumph 2
T swallowing my pride and asking a basic question Triumph 2
R more basic questions MG 4
Tinkerman Having fun with my SU H6's Basic Question Triumph 6
B Really basic question FORUM Help 2
M TR2/3/3A Basic TR3 Operator's Manual Triumph 28
M Basic toolbox Triumph 66
T Here's are some basic questions for you.... Spridgets 9
2 Basic Electrical Info Triumph 5
T Basic trunnion question Triumph 5
D BN7 - Basic Carb Settings Austin Healey 2
bmurphy7369 The basic Lucas/OPUS 1975 xj6 era principles??? Jaguar 9
Nunyas Alternate "basic" transportation... Other Cars 29
LeeMcKee Basic carb system question Triumph 3
J Why nobody offer a basic 5 sp conversion kit. MG 3
G mazda 3 2005 accessorized[new] OR 2006 basic[new]? Other Cars 2
txtr3 basic ignition timing question Triumph 3
S New to the forum. Some basic questions. MG 5
R Zenith Stromberg basic adjustment Triumph 1
Sherlock Basic tools of the trade Restoration & Tools 31
Basil The new Kia E-Type? Jaguar 5
H TR4/4A A-type overdrive pump Triumph 4
Got_All_4 TR6 Refurbishing gearbox with A type overdrive Triumph 7
P Wanted E type spare tire bracket Jaguar Classifieds 2
P Wanted 62 E Type spare tire bracket Other British Classifieds 1
Got_All_4 TR6 Routing Speedo cable for a J type tranny in my TR250 Triumph 4
Got_All_4 TR5/TR250 Trying to figure out rear transmission mount with a J type tranny Triumph 9
I GT6 A type OD vs D type - engagement speed? Triumph 3
J For Sale Jaguar E Type and MK2 spares Jaguar Classifieds 0
D TR2/3/3A Type A overdrive not engaging Triumph 0
D TR2/3/3A Type A overdrive not engaging Triumph 16
S For Sale Lotus Elan Factory Workshop Manual on CD/ROM - Type 26 - 1963 - 1965 Other British Classifieds 0
B Resistor type vs non-resistor type spark plugs for 100-6 Austin Healey 17
K TR4/4A TR4 Fuel Gauge'"light bulb socket" type? Triumph 11
Martinld123 H Type Carburetors BN2 M version Leaking Fuel At Jet Bearing Area Austin Healey 18
AH67 Heat Shield finish 66 Type Jaguar 5
AUSMHLY Grease type for zerk fittings Austin Healey 7
M TR4/4A A type Overdrive Oil Leak Fix Triumph 3
M 5-speed, 1968, 4.2, E-Type, OTS Jaguar 3
M e-type siries 1.5 shock abosorbers Jaguar 3
B TR2/3/3A 'A' type Front calipers, TR3 vendor??? Triumph 7

Similar threads