A-Frame Top Bolt Issue

[jboot51]

Hello all,
First time poster.
I've got a 1995 130 single cab that I've owned since 1996.
It's been sitting in my front yard for nearly 7 years without much care or attention. Occasionally driven down to the corner store, but thats about it. Over the last few weeks I've decided to get it back into running order, starting with the suspension, bushes and ball joints.

All I've done so far is pull the A-frame out in preparation for a new ball joint and bushes.
Here is my first problem.
referring to part# BH612321
The bolts that go through the chassis bracket/A-Frame Arm, when removed showed signs of wear on the THREAD of the bolt.
Not good I thought, wasn't an issue as I ordered all new bolts for the suspension, But the new bolts are exactly the same.
I just stuck the bolt through the bracket and have marked it with a texter, I require approx. 20mm more shank to make it all the way thru the bracket.

Am I right to assume the shank of the bolt should be just shy from coming thru the chassis bracket?

Cheers,
Tony

[uninformed]

in perfect practice yes. As long as you dont bottom out the thread before the correct torque is applied. You can take your bolts to a fastener shop and buy the same DIA and GRADE bolt in a longer shank. It will probably be to long, just cut off the extra thread with a hacksaw and file clean for nut fitment

[jboot51]

Thanks uninformed.
I'll go to a bolt place sometime this week.
I probably should send the supplier a polite email to let them know about this issue, as it did come from a reputable rover parts supplier.

[rick130]

They will be the correct bolts you were supplied, that's just typical of a mass produced item.

If you want to, just do as Uninformed suggested, and FWIW I used to have to do the same thing with all the bolts on every open wheel race car I ever rebuilt/worked on that had a bolt through a clevis in double shear.

[justinc]

You would be hard pressed to find the correct length high tensile 7/16th UNF bolt IME, I have tried before. The thread does look like it has been 'filed' slightly on its OD, looks to be 'rounded' rather than sharp, that seems to be pretty much the same as all the others I have removed and inspected over the years. And that would be PLENTY:D


JC

[jboot51]

had to google " double shear ", Learning something new everyday.

These new bolts don't have a Grade stamped on them.
The old ones are UNF Grade "S"

[jboot51]

You would be hard pressed to find the correct length high tensile 7/16th UNF bolt IME, I have tried before. The thread does look like it has been 'filed' slightly on its OD, looks to be 'rounded' rather than sharp, that seems to be pretty much the same as all the others I have removed and inspected over the years. And that would be PLENTY:D


JC
Mine are worn real bad, thread is totally gone, worn smooth.
Probably the cause of the clunking from the the rear, as the ball joint was near perfect, apart from the deteriorated boot

[rick130]

You would be hard pressed to find the correct length high tensile 7/16th UNF bolt IME, I have tried before. The thread does look like it has been 'filed' slightly on its OD, looks to be 'rounded' rather than sharp, that seems to be pretty much the same as all the others I have removed and inspected over the years. And that would be PLENTY:D


JC

I think we're talking about the chassis end JC, the 19mm ones ?

and FWIW I really don't like industrial HT bolts somewhere like suspensions, most aren't nicely made and most available here come from a country where standards aren't rigidly adhered to, if at all.

Socket head cap screws from SPS Unbrako and Holo-Krome are generally are far better made to better tolerances with better heat treatment than the average hex headed bolt, or at least that's the way it was when i used to screw cars together.

Unfortunately the really good fasteners that are available in grip (unthreaded shank) length increments of 1/16" (aircraft hardware) are only available in Imperial sizes :(

[uninformed]

had to google " double shear ", Learning something new everyday.

These new bolts don't have a Grade stamped on them.
The old ones are UNF Grade "S"

its only metric that have a numeric grade stamped on them...ie 8.8, 12.9 etc. UN bolts have "dash" indicators stamped onto the head.

[justinc]

I think we're talking about the chassis end JC, the 19mm ones ?

and FWIW I really don't like industrial HT bolts somewhere like suspensions, most aren't nicely made and most available here come from a country where standards aren't rigidly adhered to, if at all.

Socket head cap screws from SPS Unbrako and Holo-Krome are generally are far better made to better tolerances with better heat treatment than the average hex headed bolt, or at least that's the way it was when i used to screw cars together.

Unfortunately the really good fasteners that are available in grip length increments of 1/16" (aircraft hardware) are only available in Imperial sizes :(


Ah, oops sorry misread. :o


jboot51 I have some in good nick if you are interested? You are going to need the chassis brackets, too I reckon. PM me

JC

[rick130]

Ah, oops sorry misread. :o


jboot51 I have some in good nick if you are interested? You are going to need the chassis brackets, too I reckon. PM me

JC

Mine did the same thing eight years ago, but the clevises were ok. (the steel tube in the bushes were flogged out too)

Replaced the bolts with genuine (much to my dismay at having a thread through the clevis) and used Super Pro bushes, and also wrapped the bolts with shim stock to make up for the small discrepancy between the bolt and new steel bush ID and haven't had to touch them since.

Yes, I'm anal :(

[jboot51]

Sorry for any confusion, these are the 3/4 UNF bolts at the chassis end of the A-Frame

Item #6 in this pic Land Rover Parts - TOP LINK, FULCRUM & BALL JOINT - DEFENDER (http://www.roverparts.com.au/top_link__fulcrum___ball_joint___defender_?b=1)

[Sirocco]

Sorry for any confusion, these are the 3/4 UNF bolts at the chassis end of the A-Frame

Item #6 in this pic Land Rover Parts - TOP LINK, FULCRUM & BALL JOINT - DEFENDER (http://www.roverparts.com.au/top_link__fulcrum___ball_joint___defender_?b=1)

Sorry for dragging up an old post, but what are the specs of these bolts?

3/4 UNF
Length?

I can get some from town but I only have the Defender so cant take out to show them! Doubt they will have imperial anyway but worth a shot I guess. need to order new Superpros now too (because I didn't replace the bolts 12 months ago).

G

[jboot51]

4 inch bolt, but the thread will be inside the bracket.
I must have used a 6 inch bolt and cut it down, with a washer either side to get shank all the way through.

[jboot51]

Edit that..

Google says..........
Size: 3/4"
Thread: UNF
Pitch: 16 threads per inch
bolt length approx shank length
3" ......... 1 1/4"
4" ......... 2 1/4"
5" ......... 3 1/8"

A 5 inch bolt will have 7/8" more shank which will be the 20mm I was looking for.

[fraser130]

Forgive me if I'm wrong, but isn't the clevis supposed to clamp on the inner tube of the bush so that there is no movement of any metal-to-metal components, and the rubber takes all the movement? Then there should be no wear on any components?

Cheers,

Fraser

[Sirocco]

All I know is I fitted new bushes when I left the UK last year and now they are loose/clunking. So I am going to start again and this time put in new bolts :D

So you think it should be a tight fit between the bolt and the inner sleeve of the bush?

G

[rick130]

Forgive me if I'm wrong, but isn't the clevis supposed to clamp on the inner tube of the bush so that there is no movement of any metal-to-metal components, and the rubber takes all the movement? Then there should be no wear on any components?

Cheers,

Fraser

All fine in theory, except the standard bolt has too sort a grip length as it's an industrial bolt and so the threads are sitting in one side of the clevis.

Rolled threads are undersized compared to the bolt body, and under load will start to move and deform, leading to the bolt and clevis flogging out.

The crush tube ID is also quite a bit larger than the bolt shank OD, etc. leading to relative movement.
Bolted joints in shear should have little scope for movement anywhere, and should be close tolerance between all surfaces.

Bolts in double shear should not have thread bearing on the clevis.
This is why air frame bolts go up in 1/16" grip (shank) lengths.

[blackapache]

Mine did the same thing eight years ago, but the clevises were ok. (the steel tube in the bushes were flogged out too)

Replaced the bolts with genuine (much to my dismay at having a thread through the clevis) and used Super Pro bushes, and also wrapped the bolts with shim stock to make up for the small discrepancy between the bolt and new steel bush ID and haven't had to touch them since.

Yes, I'm anal :(

Me too - you don't remember what thickness shim stock you used by any chance do you Rick?

[rick130]

Me too - you don't remember what thickness shim stock you used by any chance do you Rick?


Hi Jesse.

Nope, too long ago, it would have been whatever fitted.
I usually have a pack or two of shim stock in steel and brass in various thicknesses, so whatever fitted.

In an ideal world I would've turned up a new tube and bought an AN airframe bolt if it is imperial (at vast expense in that size)

[blackapache]

Hi Jesse.

Nope, too long ago, it would have been whatever fitted.
I usually have a pack or two of shim stock in steel and brass in various thicknesses, so whatever fitted.

In an ideal world I would've turned up a new tube and bought an AN airframe bolt if it is imperial (at vast expense in that size)

Thought I might be pushing my luck. I ordered a new set from rover parts today, only because I just put super pro bushes in about 3 months ago and I wanna get this done - hopefully I haven't flogged out the bush tubes already..? I thought the MR Auto boys woulda mentioned the bolts being flogged when they pressed in the bushings on the A frame... I haven't pulled the bolts yet to confirm so maybe it's not even the case though I'm guessing it is.

Hopefully the brackets themselves aren't eyed out too. They are a fair bit more expensive than a $10 set of bolts from roverparts.

I checked out the unbrako website, they make some nice stuff, you don't generally associate "made in India" with quality but these guys looked legit. I'm thinking I might get some turned in the near future, get some made to perfect tolerance for the superpro - it's all I'll use from here out anyways and if the tolerances and shank length were spot on might be a one time job - well with that and the adjustable a frame they'll probably outlive me. im guessing superpro would have the available measurements for the inner tube I.D and getting the bracket width for shaft length is easy enough... Worst case I'd have to bust out the vernier calipers I guess..

For now though I guess I'll pull the bolts and while I'm there I'll replace them anyways, check the brackets and the bushes too.

Wish me luck.