Top mount bolt sheared

[bobbe]

Hello,

I have sheared a top mount bolt - see photo:

You cannot view this attachment.

I misread a torque setting and it went. Needless to say I didn't repeat the mistake with the other bolts - they're all fine

So - a few questions:

Should I be able to replace this bolt myself by reaching up through the wheel arch? I can see it and can reach it easily with my hand

Where can I source these bolts from? MR2-Ben has nuts but no bolts

I need have it in at the garage to change a hub on that side anyway before its MOT (the wheel bearing is going) - am I best just providing them with a new top mount as well and getting them to do it all in one go?

How safe is the car to drive in the meantime?

Thanks in advance for any help or advice!

[Dev]

You will have to remove the strut and replace the stud. I would hammer out the old stud and when you place in the new one use a bolt to tighten as the stud seats by being pressed in.

I was able to drive like this without any issues as I snapped one as well using too big of a torque wrench and after a few years I had my struts rebuilt and at that time I had the company replace the broken stud. I cant say for sure that it would be safe but in my case I had no issues.

 

[bobbe]

In that case I'll have a chat with the garage and see if it's easier (i.e. cheaper) to replace just the stud or to replace the whole top mount

It's a 20 year old car and as far as I know none of the suspension has ever been refreshed, so maybe a new top mount might not be the worst thing to do anyway. I had already been considering replacing the top mounts and shocks, so I might get two top mounts, two shocks, and two hubs and get it all done in one go (though my bank balance would not thank me). And I just sold my other car and had planned to put some of the money from it to a suspension refresh on the MR2 anyway...

Something to think about

Good to know you were able to drive like this with no problems, though the MOT is due in December and I assume this would be a fail, so that puts a time constraint on things

Thanks!

[Dev]

I think a refresh of the suspension is not a bad idea but you shouldn't have to replace the hubs unless there is a bearing issue. The hubs are not particularly a wear item for the lifetime of the car but like everything else one can go bad but its rare. If it does I would just buy a good used salvage hub and save time and labor.
 
 I would just replace the stud and at a later date I would do an entire suspension refresh. If you only do two of them then it would be unsafe in my opinion.

[Ardent]

I always get a price from Mr T.
At least your know what the worst case scenario is.
Somethings he is no more expensive than anyone else.

[Carolyn]

This is why I'm no fan of torque wrenches in most applications (not all, but most).  If you had relied on 'feel' to make sure it was snug, you wouldn't have sheared the little bugger.  Always using a torque wrench prevents learning 'feel'.

If you have the plastic surround in place, the MOT man can't see it.  And even if they could, I'll wager it would not get spotted as it's not on his/her 'to do' list.

As Dev says, the two remaining studs will suffice.

Mind you, a suspension refresh is always money well spent and, often, an eye opener as to how well these cars drove when new.

[Joesson]

I'm a little intrigued as to why you were checking the torque/ tightening these nuts.
To remove the strut, to replace the broken stud you would need to undo the two remaining nuts after undoing the ABS bracket and the brake hose fixings to the strut followed by the two strut securing bolts.
The whole assembly is then removable.
Likely easier to remove the stud on the bench than in situ.
Replacing is the reverse procedure as they say.

[bobbe]

I think a refresh of the suspension is not a bad idea but you shouldn't have to replace the hubs unless there is a bearing issue. The hubs are not particularly a wear item for the lifetime of the car but like everything else one can go bad but its rare. If it does I would just buy a good used salvage hub and save time and labor.
 
 I would just replace the stud and at a later date I would do an entire suspension refresh. If you only do two of them then it would be unsafe in my opinion.

The wheel bearings on both sides are indeed on the way out, hence new hubs

[bobbe]

I'm a little intrigued as to why you were checking the torque/ tightening these nuts.

Removing the front strut brace so I could remove the frunk plastic surround so that the local ATS - who were doing a handy £37 deal on aircon recharge - can get access to the aircon recharge port, which involved doing the nuts back up again so the suspension doesn't fall off when I drive round the corner to the garage on Tuesday

[bobbe]

This is why I'm no fan of torque wrenches in most applications (not all, but most).  If you had relied on 'feel' to make sure it was snug, you wouldn't have sheared the little bugger.  Always using a torque wrench prevents learning 'feel'.

If you have the plastic surround in place, the MOT man can't see it.  And even if they could, I'll wager it would not get spotted as it's not on his/her 'to do' list.

As Dev says, the two remaining studs will suffice.

Mind you, a suspension refresh is always money well spent and, often, an eye opener as to how well these cars drove when new.

In fairness, if I had read the prescribed torque setting properly then I probably wouldn't have sheared it either!

Unfortunately the plastic surround has cut outs for the strut brace, so I can't hide it below that. Though I suppose I could get some bolt caps, there's probably enough of the bolt left that I could cover it up (and obviously cover up the others as well) and make it look quite innocuous

[TheTigerUK]

This is why I'm no fan of torque wrenches in most applications (not all, but most).  If you had relied on 'feel' to make sure it was snug, you wouldn't have sheared the little bugger.  Always using a torque wrench prevents learning 'feel'.

If you have the plastic surround in place, the MOT man can't see it.  And even if they could, I'll wager it would not get spotted as it's not on his/her 'to do' list.

As Dev says, the two remaining studs will suffice.

Mind you, a suspension refresh is always money well spent and, often, an eye opener as to how well these cars drove when new.

Over many years I tightened 1000s of nuts and bolts as an engineer and very seldom used a torque wrench as my feel and experience was good enough and was actually checked by quality departments a few times and I passed no problem.

[McMr2]

Over many years I tightened 1000s of nuts and bolts as an engineer and very seldom used a torque wrench as my feel and experience was good enough and was actually checked by quality departments a few times and I passed no problem.

There's no mistaking the first time you're tightening up a bolt and it goes tighter, tighter, tighter...then suddenly starts feeling loose.

Torque wrench useful for checking but agree no substitute for feel.

[Joesson]

There's no mistaking the first time you're tightening up a bolt and it goes tighter, tighter, tighter...then suddenly starts feeling loose.

Torque wrench useful for checking but agree no substitute for feel.

My first experience of that feeling was when in a machine shop, operating a Universal Milling Machine.
The work pieces were sometimes held down by a system of clamps held by tee nuts, studs/ bolts and nuts, all being used repeatedly over and over again, until, that feeling when the weakest part, in my case the ( 1/2 inch) stud / bolt broke!
Not a question of over tightening more a demonstration of metal fatigue but with the same result over a longer time period.

[Dev]

 I use to tighten everything by feel but on this one occasion in 2005 I did it with a torque wrench after installing expensive coil overs because it was satisfying. The problem was not using a torque wrench, it was the kind of torque wrench. The larger clicker type is not good for small bolts as it requires more force for it to click which can easily exceed its set torque figure and snap the stud. It was also cheap made in China.
I now own a very expensive electronic torque wrench I bought used that buzzes your hand and has a visual display of lights as you get close to your torque figure. Its overkill but I enjoy using it.

There are some bolts I found on my other car (caliper bolts) that even if I tighten them to what I think they should be as far as good and tight would still not be enough and therefore I am using the torque wrench more these days.

[Ardent]

I like torque wrenches.

Have 2 now. Recently got a 2-24 to complement the usual 30+.

Just serviced the CT200H, sparkies and ignition coils all at their respective settings.

Up till now had only been serviced by lexus.
The engine in question has an elaborate filter housing cap. (Designed to make life difficult for the home servicer)
Anyway, there was a tippex type mark on the cap and mount. Suggesting when lined up that would be correct.
Guess what. No it wasn't.
The lines where lined up before removing. And it was a bugger to remove. Why? Simple over tightened. The cap clearly states. 25nm. Which those that work by touch/feel will know to be a good hand tight.
I used the torque wrench after tighting hand tight and clicked out almost immediately. The lines where about 5 mins apart. Shocking. Or not.
Maybe some people mistake nm for ft/lbs.

[Joesson]

As I've mentioned previously and elsewhere on here: Such is progress!

[Carolyn]

This thread has been seriously hijacked guys,.  I'm tempted to edit from when the discussion completely left the realm of the MR2.

Thoughts??

[Ardent]

Fine by me, I'm used to it. 

[TheTigerUK]

Its good to talk !!

[Joesson]

All things in moderation, including moderation.
Oscar Wilde

But if you give someone an inch- lb  they  will take a  ft- lb !

[Ardent]

Back on topic.

I expect it will be resolved before the December mot but

If you still have the bit that sheared off, so things look normal could you not use a dab or a splodge (technical term) of hot glue to stick it back on.

Just for the mot. But if changing hub likely to end up with new bolt or top mount.

[bobbe]

If I haven't got round to replacing it by then, I might well do!

[Ardent]

@bobbe

https://www.mr2roc.org/forum/index.php?topic=73133.0