Another bit of a to tighten question.

[Aristotle]

Thought I'd spend Bank Holiday Sunday in repose lying on my back under my 1500 Spitfire, just checking things out as you do.

I have got a bit of a clonk on initial pick up thought to be a UJ on one of the half shafts, not too much of a job thought I - just right for a Sunday.

Now whilst there is a tiny amount of play nearside in one of them the other thing I found I need a touch of advice on.

Lying on my back one hand on a road wheel the other on the offside UJ in moving the wheel it was clear the wheel moved before the shaft did - the nearside shaft moved the moment the wheel moved so that side is fine.

Off came the offside wheel and drum to reveal what you see in the photo. 

What was clear was that the large nut in the centre was a touch loose allowing the hub to move backwards and forwards as the drive takes up.

The nut was more than finger tight but with a socket and half inch drive ratchet took up sufficiently with little effort to take out the movement, I did not overtighten. My torque wrench not to hand.

Couple of questions really - the play being minimal when discovered can I just torque up the nut and use or is it likely damage will have been done to the bearing such that it would be unwise to use before replacing further investigation ? There is no lateral movement in the hub and it's well greased.

Second is - the nut appears to be nyloc would it it be wiser to replace ?

 

 

 

 

[johny]

Nut is good and difficult to over tighten it as its about the highest torqued nut on the car! Shouldnt be any problem done to the bearings either.

However the hub is keyed on to the tapered end of the drive shaft and is normally so well stuck on thats its quite a problem to release. Its a little surprising that there was movement in the hub even with the nut loose so before tightening I would have pulled it off to check the condition of the taper and key. It would have come straight off then but now thats its been tightened may need a special puller to remove as it could have now locked on to the taper as designed.

If you decide to have a look and it wont come off easily dont be tempted to use a normal puller or bash it as the metal is quite soft and distorts easily😞 

[MJH2454]

I'm no expert in these things, but from my limited knowledge and experience, recently removed the hubs to change to 12mm studs. Behind that nut is a woodruff key if you are having play then is the key loose, worn or non existent secondly that nut is supposed to be done up to some phenomenal torque, something like 120ft lbs

[MJH2454]

2 minutes ago, johny said:

Nut is good and difficult to over tighten it as its about the highest torqued nut on the car! Shouldnt be any problem done to the bearings either.

However the hub is keyed on to the tapered end of the drive shaft and is normally so well stuck on thats its quite a problem to release. Its a little surprising that there was movement in the hub even with the nut loose so before tightening I would have pulled it off to check the condition of the taper and key. It would have come straight off then but now thats its been tightened may need a special puller to remove as it could have now locked on to the taper as designed.

If you decide to have a look and it wont come off easily dont be tempted to use a normal puller or bash it as the metal is quite soft and distorts easily😞 

Exactly what Johny said

[Aristotle]

14 hours ago, johny said:

Nut is good and difficult to over tighten it as its about the highest torqued nut on the car! Shouldnt be any problem done to the bearings either.

However the hub is keyed on to the tapered end of the drive shaft and is normally so well stuck on thats its quite a problem to release. Its a little surprising that there was movement in the hub even with the nut loose so before tightening I would have pulled it off to check the condition of the taper and key. It would have come straight off then but now thats its been tightened may need a special puller to remove as it could have now locked on to the taper as designed.

If you decide to have a look and it wont come off easily dont be tempted to use a normal puller or bash it as the metal is quite soft and distorts easily😞 

Thanks, (to both for your comments) very useful.

I will try to get it off and examine the key.

Just a thought though (and because I am a Bear with very little brain) as it was loose and by loose I mean the hub with the studs moved clock and anti-clock by about two to three mm before rotating the shaft. As it's on a taper does that mean the key was still engaged with the hub and shaft stopping it rotating further. Perhaps as it hadn't been torqued properly with use the hub moved outwards slightly on the taper allowing slight movement without disengaging the key ?

 

[68vitesse]

15 hours ago, Aristotle said:

Second is - the nut appears to be nyloc would it it be wiser to replace

I'd say yes.

My Mk1 Vitesse the nut is a nyloc half nut 5/8 unf from memory, plenty on eBay.

Regards

Paul

[johny]

40 minutes ago, Aristotle said:

Thanks, (to both for your comments) very useful.

I will try to get it off and examine the key.

Just a thought though (and because I am a Bear with very little brain) as it was loose and by loose I mean the hub with the studs moved clock and anti-clock by about two to three mm before rotating the shaft. As it's on a taper does that mean the key was still engaged with the hub and shaft stopping it rotating further. Perhaps as it hadn't been torqued properly with use the hub moved outwards slightly on the taper allowing slight movement without disengaging the key ?

 

The key is quite a good fit in a slot in the shaft and another in the hub so even with the nut loose there shouldnt be much rotational play. However if its been loose for a few miles it could be the key and or slots have been worn so its a good idea to inspect if possible.

The torque setting for the nut is 13.8 - 15.2 kg.m which is quite hard to achieve so maybe why it came loose....

 

[Stratton Jimmer]

Nyloc nuts should never be reused. I will always advocate throwing used ones away and fitting new every time.

[johny]

hmmm I know thats the 'correct' situation but in this case if it slackens off from 110 lb.ft I cant see a bit of plastic nyloc is going to do much....

[Aristotle]

Thanks to all for comments/advice, I'm off to investigate.

[Aristotle]

So how'd it go ?

Fortunately had not nipped it up too much and the hub came off easily with little tension on a three leg puller - just popped off really.

The shaft showed a couple of minor marks part way along the key way - rather like very small v's, clearly where the key had been rocking. Fortunately no burrs on the face of shaft adjacent to these marks.

The key itself was unmarked and the hub (again after cleaning) showed as unmarked.

Popped the hub onto the shaft without the key and the mating surface all seemed to meet and there was no lateral movement anywhere, so on the basis that the mating surfaces and the key and keyways were fine (apart from those tiny v marks) felt we were good to reassemble.

Interestingly two manuals came with the car one a Haynes the other an official BL publication dedicated to the 1500 - Haynes said torque to 120lbft the BL one 90 to 120lbft.

I torqued to 120lbft and strewth that's tight !

Thought I'd better check the other side and although there was no movement it did need tightening too, so it looks like whoever last did maintenance did not apply sufficient torque.

Road test in bright summer sunshine, top down, no noise, result.

Thanks to all for your advice.

 

[Pete Lewis]

good you caught it before it turned into a disaster  brilliant

Pete

[johny]

2 hours ago, Aristotle said:

I torqued to 120lbft and strewth that's tight !

Thought I'd better check the other side and although there was no movement it did need tightening too, so it looks like whoever last did maintenance did not apply sufficient torque.

Out of interest how did you hold the shaft to tighten to that?

[Pete Lewis]

torque  is a turning moment how its applied is down to the length of the spanner you are wielding

120 is not that tight ,its 60lb on a 2 ft wrench you can you can get 60lbft on a decent ratchet  , just double its handle length 

on truck assy we had 10 nuts per wheel at 345lbft  and for audit checks we had a torque meter more akin to a parking meter 

and U bolts on the suspension at 600lbft    its all doable with the right tooling and a following wind

one thing you need to be aware of  applying serious torque through the transmission to use the clutch and drive line to lock the engine 

120lbft far out strips the engine/drive line torque   when the herald engine produce a max torque of 40 (948) to 73 lbft 13/60)    its easy to overload the clutch damper hub 

Pete

[johny]

Youre right Pete and also transmission 'winds up' so sometimes you need a clear rotation to get to the required torque! 

[Wagger]

7 hours ago, johny said:

Out of interest how did you hold the shaft to tighten to that?

When I did mine two years ago, I used a strip of alloy around the drivesahaft and a stilson against the floor. OK it took a few goes for the stilson to lock but this method avoids loading the u/j's and the transmission. Nice long stilson though or the car may lift.

My car is a mark 1 so I am not sure that this is possible on a mk2 with rooflex. You certainly do not want to torque via the rubber donuts.

[johny]

The only way Ive managed it is by putting drum and wheel back on and lowering the car onto the ground so that with the tyre chocked plus hand brake on theres more resistance to allow further tightening of the nut...

[Aristotle]

Goodness, there's an interesting discussion how to stop the whole thing rotating whilst you whang it up tight ?

If I do it again I am drawn to Wagger's solution as I have a giant Stilson and some alloy.

When faced with the problem though I didn't fancy loading up the transmission etc and thought of putting the wheel back on and lowering it to the ground - but my mind went back to a boat I had a while ago with a Volvo three bladed folding prop.

The prop needed to come off every season to be cleaned and have new anodes and there was a jinourmous nut which had to be released and to get it off the shaft in the saildrive it had to be stopped rotating. 

Solution was a metre long rod which passed through the blade slots set against a block of wood on the ground - worked a treat.

For this problem I used similar method but with the shaft of a 3ft breaker bar passed through the hub stubs close to the base of the studs. 

Compared to Wagger's solution I suppose one could argue doing it my way there would be a sideways force being applied to the inwards force required to draw the hub inwards to ensure a tight fit, however it seemed to work well and at 120ftlbs the inwards force would probably dominate.

My thanks again to all - there will be more questions to come !