Use once nuts

[RaceDiagnostics]

Is this a common thing, I have never seen it before (they are not nylocs).

 

[Tinbasherdan]

Not come across that before, what's are they off vehicle wise

 

[RaceDiagnostics]

Jag XK8.

 

[pedrobedro]

Do they have a deformed last thread to make them lock as they go on which they lose when they are loosened ? You could replace them with nylocs.

 

[DAPPH]

Those sort of nuts on prop shafts are replace with new ones once taken off & discard the old ones . it's good engineering practice .

if it is the type I'm thinking of the top two threads on the nut have been pinched in a fraction and so grip lock onto the threaded bolt .

There is another throw away once taken off prop shaft nuts that have a thin spring steel cover over the nut &7 have bent over wings arising from each flat on the nut pointing into the centre . The wings press into the thread of the bolt when the nut is turned down they are very effective .

If you must reuse them use a spirit like petrol to clean them & put some Locktite on the threads .
I gather that nylocks or nuts with fibre inserts are not used where these are needed , due to excessive vibrations making them become loose , having them on a high speed Jag , would I guess come into that good engineering practice range

 

[AndyStobbs]

If the drivetrain rusts as quickly as the rest of the car you could use plain nuts and reasonably expect them to locked on within a week.
As for clutch plate bolts BMW and VAG seem to have a Swiss supplier for their M8 socket caps because they are like cheese.

 

[rtbcomp]

It's always been recommended that self locking nuts like Nyloc are only used once. Same applies to lockwashers.

 

[langy]

Very common on American cars, they should only be used once otherwise they will come loose

 

[rikrobson]

They will be deforming nuts. There are several types of lock nuts that deform to make a tight fir on the thread. obviously its a single use if they do.

 

[colnerov]

Hi, You could always deform the threads again with a centre punch or cold chisel across the face of the nut. It's not the first time I've seen it done 'in the field' on all kinds of nuts.

Colin

 

[rikrobson]

or just get new nuts. They can't be that expensive

 

[clift_d]

I've seen these on a VW for mounting the steering rack. Look for stover or binx type nuts.

 

[RaceDiagnostics]

I ordered a bunch of nuts and bolts from Jag today, I take a close look when I get them and stick up a picture.

These nuts were on very tight and needed a bit of heat to get them off.

 

[rtbcomp]

Sometimes the bolts come with a locking compound already on them - the ones I saw were greenish in colour.

 

[rikrobson]

the thread can be oval or tapered at the top depending on the style.
the basic theory is that it creates an interference fit at some point on the thread. This deforms the nut and therefore requires replacement after being removed.

 

[brightspark]

have u ever seen a propshaft come adrift and let go my stockcar had a 1/8 th steel plate under the seat for that verry reason.it was well dented .glad it wasnt my credentials when it did

 

[daleyd]

Used to use similar in high temp applications where nyloc ones were no use due to the elevated temperatures.

 

[roofman]

re-use with some threadlock (high strength)....

 

[Pete.]

Metal locking nuts. They aren't that expensive, why not just buy four new ones?

 

[Wallace]

Aerotight rings a bell, but the deformed head type has a different name, think GM used them.

*Cleveloc nut?