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MG TD TF 1500 - 3/8' BSF hardware (TF)

Hello again:

I would like to obtain several confirmations from TF owners regarding the shank size of hardware used at the following locations on the TF:

1. Body to chassis. I have factory documentation that states these bolts are 5/16" BSF.
The eight bolts (four per side) come in three different lengths.
However, at least two major UK suppliers supply body bolting kits that use 3/8" BSF bolts.

Could a few of you confirm for me which girth of bolt is correct?
Thank you

2. Once again the above question is also applied to the four bolts that are used to fasten the fender (wing) via the engine side panel (bonnet side) to the tie rod bracket on the engine side of the side panel.
This tie rod is just abaft the radiator, at the top end of the bay and connects to its mate, in like manner, on the other side of the car.
Thank you

Peter
TF8502
P Pichler

Peter -

My bolts for the tie rod stiffener between each side panel are buried in my box of parts, so I can't tell you the diameter and length.

The bolts that hold the body frame to the chassis have 5/16" diameter shafts and BSF threads. The heads & nuts are 1/4WW (5/16BSF). I don't remember, but they may have unthreaded shafts where they contact the body frame and chassis.

I didn't measure the length of my bolts.

> The two longest goes through the rear bottom rail and may have shims between the rail and the chassis. Mine has a hex head and a washer that partially overlaps the body rail. I believe that some cars may have used carriage bolts.

> The two shortest goes over the front pivot of the rear leaf springs. You must loosen the bolt in the spring and knock it back a little to be able to attach he washer, lock washer, and nut for the bolt in the body frame. Leave enough threads showing in the spring bolt to thread on the nut and pull the bolt back into position. Alternatively, you can probably move the head of the spring bolt though the large holes in the supports for the body frame, but it won't be easy.

> The four mid-length bolts go at the front by the roll bar and at the middle by the doors.

My body frame had thin cork shims between it and the chassis at the front three bolts.

A rubber pad goes around the roll bar on top of the body frame -- Moss #282-670.

Lonnie
TF7211
LM Cook

Lonnie, thank you for your response.

You have confirmed what appears to have been original factory specs (not a listing typo) for the body to chassis bolts, including the original cork pads used between the chassis and the body.

Both NTG and Brown & Gammons, in the UK, supply these bolts using the 3/8" shank size.
Previously, on an unrelated issue, I queried NTG about some other bolts being correct but was told that they would have to check with their supply source who does the kitting for NTG.

Accordingly, it tells me that it is a third party enterprise that is providing NTG, and most likely Brown & Gammons, with these bolts.

This may explain, perhaps, why both these suppliers are selling the potentially incorrect sized bolts for this area.

I would like to obtain some additional feedback from the community to further confirm this premise.

Peter
TF8502
P Pichler

Peter,

I am pretty sure the body tub to chassis frame bolts were 3/8" BSF bolts.
They were 'RUBERY OWEN' branded.

The current restoration of the TF1500 had these bolts in position before the rebuild.

I suspect that 5/16" diameter bolts would not be safely adequate for this area of the car.

Cheers
Rob Grantham
T3719("Aramis"),TF9177("Athos").
Rob Grantham

Peter,

If you look at the photo, No.168,'Chassis and Underside Features' of the fairly original TF9052 "(The Original mgtf" website), the bolt depicted
for the tub to chassis frame, may be a 3/8"diam. bolt ?


Cheers
Rob Grantham
Rob Grantham

Rob,

You are the TF expert, so I am questioning my response. I removed a bolt from the body frame in my TF a few minutes ago. Although the hole is partially blocked by the new cork pad between the two, it looks like a 3/8 diameter bolt can be used. I don’t know if my 5/16 bolts are original or were replaced by a previous owner.

Lonnie
TF7211
LM Cook

Thanks Rob.

My personal belief is of the same persuasion, exactly for the same reason you offered.

However, I do want to be absolutely certain as I am in the process of putting together a fastener list for TF owners/restorers.

I run into ambiguities at times in the process and need to obtain TF community consensus/feedback.

Cheers,

Peter
TF8502
P Pichler

Here is the complete bolt, nut, washer list that fixes the TD and TF tub to the chassis.

5/16 BSF 3 Hex Bolt 2 Tub Attach
5/16 BSF Nut 14 Tub Attach
5/16 ID 1 OD Flat Washer 16 Tub Attach
5/16 BSF 1 Hex Bolt 4 Tub Attach
5/16 BSF 1 1/8 Hex Bolt 1 Tub Attach
5/16 BSF 7/8 Hex Bolt 4 Tub Attach
5/16 BSF 1 1/4 Hex Bolt 1 Tub Attach
5/16 BSF 3/4 Hex Bolt 2 Tub Attach
5/16 BSF 3/4 Hex Bolt (set screw) 1 Tub Attach
5/16 BSF Lock Washer 12 Tub Attach
5/16 ID 5/8 OD Flat Washer 9 Tub Attach
5/16 ID 3/4 OD Flat Washer 1 Tub Attach

As you can see they are 5/16"

The 4 TF front wing to stay bolts are 3/8", the rest are 5/16"
Rod Brayshaw

Hi Rob and Lonnie:

Rob, I looked at photo 168 of TF9052, but it is a bit dicey to really conclude on the bolt diameter, given the oblique camera angle and associated shadowing.

However, I expanded the photo and measured the gauge (thickness) of the outrigger side web at a clear point.
I then applied this measurement against the diameter of the bolt, allowing for some compensation for the shadow and concluded that it renders a 2:1 ratio.
If this bolt is, in fact, 3/8" the ratio would dictate that the outrigger side web would be 3/16" thick (0.187") or 7 gauge.
Alternatively, if the bolt was 5/16" in diameter, the outrigger web side gauge would be 9 gauge or 0.156" thick. Are you able to measure the web thickness on your car?

Unfortunately this is only a guess, based upon questionable measurements to even create the ratio.
At 1/16" of an inch difference between a 5/16" and 3/8" bolt diameters, the expanded photo is somewhat inadequate.

Lonnie, how much clearance do you have on the tub frame mounting hole at this location?
I suspect that the tub frame hole is elongated, at least on one axis. Its the opening of the minor axis that would be more indicative whether a 3/8" bolt could be used. is the hole in the chassis outrigger also elongated or circular?

Rob and Lonnie, if you look at photo 168 again, adjacent to the footwell pan quite close to its corner, there appears to be an installed rectangular plate for a "T" nut complete with the end of the intended bolt, showing flush.
This fitting is inserted into the floorboard from he underside, much like the rectangular "T" nuts in the floorboard used to hold the gearbox cover pressing on the other side of the same floorboard.

Do either of you have any idea what this "T" nut is actually doing there? It is on the outboard side of the footwell (closest to the chassis rail) a location that is free of any fitting in the cockpit of this LHD car, as far as I know.

Peter
TF8502
P Pichler

Hi Rod:

Thank you for your reply.

As far as I am aware, there are only 8 mounting locations to affix the TF tub to the chassis proper.

There are 6 that interface directly to the chassis outriggers and 2 that connect to a welded bracket on the rear part of the chassis upswing arch to support the elevated tub back corners.

Of the 8 locations, the 4 forward most outriggers (two per each side of chassis) use 1 1/4" bolts, while the two rear outriggers, that also support the front of the rear springs, use 1 1/8" bolts due to the tight fit for the rear spring mounting on the underside of the outrigger.
The remaining 2 locations address the rear corners of the tub, employing 2 7/8" bolts.

I am aware that there is a substantial difference between the TD and TF when it comes to mounting the wings and running boards, but I was not aware that there was such a difference between the TD and TF tub mounting.

Your list uses a total of 14 bolts and one setscrew, while my understanding only defines the use of 8 bolts in total.
Perhaps semantics are at play here in terms of defining, the mounting, the tub, or the chassis.

Peter
TF8502
P Pichler

Rob and Lonnie:

I just had another closer look at the issue of the "T" nut.
I believe my previous commentary was a faux pas, so to speak.
Please disregard it.

This time around I actually enhanced and enlarged the photo which disclosed that what I thought was a rectangular "T" nut plate, is in fact not rectangular at all for one, and as well, it is not affixed to the underside of the floorboard but really is part of the angular metal channel that runs along the length of the cockpit at the bottom of the tub structure on each side.

Peter
TF8502
P Pichler

Peter,

On TFs at least, the front six (6) holes for the body tub to chassis frame,
have elongated holes running 'east- west' in orientation.

The remaining two(2) holes at the rear of the body tub to chassis run 'north -south' in elongation ie. front to rear bumper.

None of the eight(8) holes were originally 'round'.

In regard to picture 168 of TF9052, the piece you are referring to, by query I suspect, is the steel flat topped rivet which ties the 'tongue' piece of the bottom of the Bulkhead to the body tub steel frame (not the chassis frame).
There are of course a total of two(2) rivets, one on each side of the car.

Cheers
Rob Grantham
TF3719("Aramis"),TF9177("Athos").

Rob Grantham

Peter,

As Rod noted, the body frame has elongated holes for adjustment running North-South (parallel to the sides of the car) and the chassis has elongated holes running East-West. The hole in each bracket at the far rear of the car under the tank board is elongated North-South. The hole in the wood rear bottom rail through which the mounting bolt passes can be elongated as needed.

The elongated holes are .450" wide X .735" long. Should be plenty of room for a 3/8" (.375") bolt.

My TF is held together with bolts and clamps for a club Shop Tour tomorrow. I'll be disassembling in a couple of weeks and will check the fit of 3/8" bolts.

Lonnie
TF7211

Photo:
Mounting hole in body frame, second from front. Bolt is 5/16". Drill bit is 3/8".



LM Cook

Lonnie and Rob, thank you both for persisting with me on this aspect of the TF and the details provided.

Lonnie I look forward to your follow up test results post your club meeting.

Rob, do you still have a source for the rubber buffers for the TF battery retaining clamp?

Peter
TF8502
P Pichler

Peter,

I use to have manufactured the TD/TF Battery Bar Rubber Buffers here in WA. However, after doing an initial run, the company then unfortunately closed down due to the owner retiring.

I consequently went to seek out another manufacturer and the price per unit was ridiculously too high.

I still have the original mould made up for me. I think it is a resin based/alum
based structure.

I would be willing to loan the mould if someone can come up with a reliable
company to manufacture some of the Buffers ?

Cheers
Rob Grantham

I
Rob Grantham

Hello Rob:

Not being familiar with the rubber manufacturing process, I would like to know a bit more about it.

Is there a possibility you could get a hold of me via email?

This reply lists my email address.

Cheers,

Peter
TF8502
P Pichler

My apologies, I did a quick computer search and found a decades old list that I did not check for accuracy before I posted it.

This morning I went to my bolt bin and found that the 6 TF chassis point bolts that go through the angle irons are 3/8" the others are 5/6" rear 2 and goal/post 4

The TD only uses 4 through the angle irons.

We use 1" where we can but often need 1-1/8" or sometimes 1-1/4" depending on packers for door fit etc.

Rob is correct on the TF slot orientation but the TD has the rear slot north south like the other 4.

Now there is a question for quizzes!
Rod Brayshaw

<<I would be willing to loan the mould if someone can come up with a reliable
company to manufacture some of the Buffers ? >>

How about Delcan Burns?

Frank

TF1414
Frank Cronin

Rod,thank you for the update on your earlier post.
I am glad that you were able to confirm the 3/8" bolt usage for the TF body to chassis fixing, as well as the geometric orientation of the associated holes.
Rob Grantham stated earlier that his were original Rubery Owen 3/8" bolts when he worked on his TF.

Peter

P Pichler

This thread was discussed between 06/06/2019 and 11/06/2019

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