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I think I remember this happening thirty-five years ago...

Having (almost) sorted the back end, I'm now dismantling the front suspension for attention.  Apart from one fractured bolt in the upright (the only one that does nothing except retain the dustshield), it's come apart very nicely.  With one exception... Triumph in their wisdom, obviously assembled the lower wishbone to the car before fitting the suspension turret.  The front wishbone bolt cannot be removed with the turret in position, and removing requires removing the engine mount and possibly disturbing the KPI setting, albeit minutely.  It reminds me of the Morris Minor brake master cylinder, first removal of which requires complete disassembly of the driver's side front suspension and torsion bar.

I presume the answer is a cutting disc and a new bolt, inserted from the front?

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I know you have to fit most of the bolts before fitting the spring / shock assembly, but if you mean the chassis brackets must be attached to the lower wishbone first and then bolted to the chassis, it's much easier than trying to fit them with the bracket already on the car. Removal is just the reverse - unbolt the bracket from the chassis inner rail by undoing the single nut on the inner face and push through. You don't need to take the turret / engine mounting off. Remember to count the shims and replace with the same number as a starting point. 

There's also one bolt that fits 'back to front' through the chassis brackets, which have a flare on one side to hold the bolt head and prevent it rotating. The brackets are not handed so in order to get the head, not the nut, to the correct part of the bracket, it needs to be fitted in the opposite direction to the others.

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30 minutes ago, Roger K said:

I think I remember this happening thirty-five years ago...

Having (almost) sorted the back end, I'm now dismantling the front suspension for attention.  Apart from one fractured bolt in the upright (the only one that does nothing except retain the dustshield), it's come apart very nicely.  With one exception... Triumph in their wisdom, obviously assembled the lower wishbone to the car before fitting the suspension turret.  The front wishbone bolt cannot be removed with the turret in position, and removing requires removing the engine mount and possibly disturbing the KPI setting, albeit minutely.  It reminds me of the Morris Minor brake master cylinder, first removal of which requires complete disassembly of the driver's side front suspension and torsion bar.

I presume the answer is a cutting disc and a new bolt, inserted from the front?

Yes, cutting the bolt will do it. Or you can remove the wishbone brackets off the chassis. (been a while, but I am sure that is possible.

Now, as I know you like things done properly..... (from http://www.wolfitt.com/  products page, sorry but pics wont copy)

Front suspension bolts (upper and lower)

Triumph Spitfire, GT6, Herald, Vitesse and small Triumph chassis based kit cars

The problem The standard bolt is not long enough, so the thread is used as a bearing surface which can lead to appalling and dangerous wear on the bolt. (see pictures)


Standard bolt (unbelievable that this was acceptable to Triumph)


Typical bolt wear - this came from a car which had passed an MOT!


Longer bolt with the shank passing through the entire mounting bracket.
Each bolt is supplied with a new nyloc nut and washers to ensure that the bolt does not stall
on the shank. Bolts can be trimmed to length if required.

The solution Bolts which are the correct length!

These bolts can also be used on the rear radius arms on non-rotoflex small Triumphs but more washers may be required, as the mounting bracket on the body and front of the vertical link is typically slightly narrower than those on the front suspension. 

 

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agree undo the bracket studs its only one nut per brkt,  and the bracket studs can rust badly Ive seen some so thin they just shear 

when undoing   so well worth examining  anyway.

and yes  do photo how they fit or you will get very odd geometry if you refit as you think is logical youre wrong  one up  & ones down 

Pete

 

 

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All makes good sense.  Doh - I'd forgotten that the wishbone brackets are removable - obvious for shimming purposes.  It is rather astonishing that Triumph chose bolts whose shanks do not extend to the bearing surfaces, incredible.  Thanks for pointing this out - for the only one I've removed so far, a) I didn't notice it was too short and b) it's not worn at all in the threaded portion.

I'll be doing a full alignment on reassembly anyway.  Photos are always a good idea....

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7 hours ago, Roger K said:

I think I remember this happening thirty-five years ago...

Having (almost) sorted the back end, I'm now dismantling the front suspension for attention.  Apart from one fractured bolt in the upright (the only one that does nothing except retain the dustshield), it's come apart very nicely.  With one exception... Triumph in their wisdom, obviously assembled the lower wishbone to the car before fitting the suspension turret.  The front wishbone bolt cannot be removed with the turret in position, and removing requires removing the engine mount and possibly disturbing the KPI setting, albeit minutely.  It reminds me of the Morris Minor brake master cylinder, first removal of which requires complete disassembly of the driver's side front suspension and torsion bar.

I presume the answer is a cutting disc and a new bolt, inserted from the front?

Roger, we are clearly doing the same jobs in the same place!

I too scratched my head at that one this afternoon but can now attack it anew this week. My current struggle is the TRE and getting them off the steering arm, but that’s a story for a different thread... (any tips?)

Good luck with the refurb 👍🏼

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My usual method for releasing balljoint tapers is to loosen the nut on the taper pin, then whack the side of the steering arm with a decent hammer.  This usually shocks the pin out of the tapered hole.  Loosen the nut past the nyloc section, otherwise it can be tricky to undo as the ball will rotate in the joint when you try to undo it.  Sometimes holding another hammer on the other side of the steering arm can help, but not usually necessary.

Failing that, the usual armament of ball joint removal tools.... if using the screw type, fit it so it's putting pressure on the pin, then whack the side of the steering arm with the hammer.  That should do it.

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yes over 50 years of whack the hole not the pin has always worked for me 

the stg arm or what ever does need to be in a position to 

not be springy so all the effort is passed into the body of what youre hitting 

and enable a right good solid whack with a 2lb hammer , on a decent handle  to get a good swing at it 

a short club hammer wont get a good swing 

pete

 

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On 24/01/2021 at 15:14, Roger K said:

All makes good sense.  Doh - I'd forgotten that the wishbone brackets are removable - obvious for shimming purposes.  It is rather astonishing that Triumph chose bolts whose shanks do not extend to the bearing surfaces, incredible.  Thanks for pointing this out - for the only one I've removed so far, a) I didn't notice it was too short and b) it's not worn at all in the threaded portion.

I'll be doing a full alignment on reassembly anyway.  Photos are always a good idea....

Hi Roger,

that appears to be an old British practice on cars. Short shank and loads of thread - utterly daft.

In aerospace the shank is always that load bearing section and you never have components sitting on threads.  Correct shank with adequate thread for nut and locking.

Modern cars have finally come round to that thinking also.

I suspect the short shank / long thread was a cost saving practice - where you can use that bolt in many places and still tighten the nut.

 Roger

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I had a similar issue on my prop to diff joint (subaru diff) The diff will cope with 300+bhp, but used 8mm bolts. teh same as a herald/early spit.

I wanted 12.9 grade bolts, the easiest was is cap heads. But the correct length bolts would have had threaded section at the shear point. So a trip to Namricks (5 mins door to door) with a ruler, and found cap heads with enough unthreaded shank in black bolts (I avoided plated). Got home, a tickle with the 1mm cutting disc and perfect length, 1-2 threads sticking out beyond the nyloc. I later found genuine subaru bolts for sale, but declined at about £10 EACH.

 

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9 minutes ago, Peter Truman said:

The Triumph speciality always got me of using UNF threads in alloy, Why, UNC is required or the thread will strip! I think I read somewhere it was a Harry Webster spec, obviously a personal hang up! Because there was no logic in it.

 

Hi  Peter,

there is total logic. 

Regarding the rear suspension trailing arms (on the IRS cars) the UNF thread is specified as the torque loading is very small (16 lb.ft).

With this low loading the UNF thread is able to withstand undoing by vibration due to the more oblique thread angle. it could be posible for a UNC tread to vibrate loose.

I accept a UNC thread with a higher torque load looks more correct but perhaps the torque could not be increase. The increase in material cross section with UNC compared to UNF is marginal. So a low torque load controls the thread form.

 

Roger

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2 hours ago, RogerH said:

that appears to be an old British practice on cars. Short shank and loads of thread - utterly daft.

It appears to be a policy from some suppliers too. It's not that the bolts aren't available, it's just whatever they decide to supply. The bolts for my TR7 rear suspension had too much thread and insufficient shoulder, so not being happy with that I went online and very easily found the proper length with a shoulder that completely cleared the mountings. I believe that a threaded section through a metal panel is bound to wear much more quickly than a full shoulder, either wearing the mounting or the bolt itself, as the threads will wear more quickly than the solid metal thereby allowing movement.

DSCF7152.jpg.09b21670d5fff1228893a93f06dd782d.jpg  DSCF7164.jpg.31a20392687dfc46e643ba927b505d6c.jpg

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1 minute ago, Colin Lindsay said:

It appears to be a policy from some suppliers too. It's not that the bolts aren't available, it's just whatever they decide to supply.

Actually it is a question of availability to an extent. The standard, commonly available bolts have a generous amount of thread - typically 30% of the length or 1". If you specify the correct length of shank for one of the suspension brackets, this means the thread pokes way out beyond the nut... and fouls on something nearby. The correct long shank, short thread bolts are special order.

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I would happily order bolts with the correct length shank, then cut the thread down to size.  Unfortunately I don't know a supplier who lists the shank length, only the overall bolt length.  If anybody knows who can give this information, I'd be grateful.

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5 hours ago, NonMember said:

Actually it is a question of availability to an extent. The standard, commonly available bolts have a generous amount of thread - typically 30% of the length or 1". If you specify the correct length of shank for one of the suspension brackets, this means the thread pokes way out beyond the nut... and fouls on something nearby. The correct long shank, short thread bolts are special order.

It's just me being picky as usual Rob, but if the bolts are available I always wonder why the suppliers never stock them. I have quantities of nuts and bolts that suppliers have sent, and I've replaced them - often quite easily - with better or more suitable items that were readily available. If a supplier charges me, say 25p for a bolt, and I can buy the 'proper' version elsewhere for 30p, why doesn't the supplier simply charge me the 30p for the better item? We had this debate a while back about suppliers substituting metric parts for Imperial, so that they were an approximate fit, yet the correct Imperial sizes are available to anyone that searches online. And I frequently have to!

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