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navigation2000
13th September 2008, 04:05 PM
Hi everyone,

Had a bit of a moment today with the spare wheel mounted on the bonnet.

It was formerly residing in the cargo area, mounted against the drivers side bulkhead in the correct fashion, yet I thought I'd just throw it up on the bonnet and leave it there. No real reason for doing so, just thought I'd give it a run.

That was about a week ago, and I've been under the bonnet quite a few times since, just checking things out.

Anyway, for some reason I thought I'd climb up on the bullbar this morning and just check the tension on the fasteners.
I was shocked to discover they were literally hanging off.

The wheel holder had sheered all but 1 rivet and all just about come adrift.:o

I immediately took the wheel off and confirmed that all but 1 rivet had failed.

On closer inspection, I found that most had been broken for quite a while, and it's probable that only 2 or 3 rivets out of the 9 were ever doing their job.

How I failed to noticed this has rocked me, for I am usually quite an observant person, especially when it concerns safety.

I was going to re-rivet the plate back on, but closer reflection has told me that the idea of using rivets was not really very practical from a safety standpoint. In defense of the poor old rivets which failed, they are 1978 models, so I guess they can be forgiven to a degree.

Rivets can easily sheer when a 1/2 decent amount of force is applied, and given the forces apparent in a vehicle collision, I feel the rivets could potentially add a missile to the equation in the form of a spare wheel.

I opted to drill the holes out just a pinch, then fit high tensile bolts and nylok nuts.

This approach now firmly secures the plate to the bonnet, and you can see that the bonnet substructure appears to enjoy he extra support.

I'd suggest everyone consider making this modification, it doesn't take long or cost much.

I realise that nothing will stop the spare wheel taking the bonnet with it, in the event of a serious collision, but I reason that the hangers on the bulkhead will lessen the likelihood of that.

How lucky was it that I noticed the loose fasteners?:eek:

Fortunately all's well now that I've rectified the problem, and I dare say that the wheel will be staying put from here on.

Can somebody please link me to a picture of the fasteners please, the ones I have don't match, one is long, the other is short, and I suspect that while they're doing the job, they would do it better if they matched, and I want to make sure I have that wheel fastened correctly as soon as possible.

Regards,
Ross.

JDNSW
13th September 2008, 04:25 PM
Interesting post. I have never known rivets holding the bonnet mount on to fail, and I'm quite surprised - probably a combination of corrosion and fatigue. If you are concerned about the strength of rivetting from a safety point of view, think of it next time you travel on an aeroplane - these are mostly rivetted aluminium structures, and in the case of smaller aircraft have major structural joints not very different from the one you are talking about!

Having said that, it also needs to be considered that when that carrier was designed, the standard tyre was 600x16, and I certainly would not consider using it for anything above 7.50x16 - other things apart, the bonnet is too heavy to lift, and the tyre is too hard to get on and off.

If by fasteners you mean the bits that hold the wheel down, the usual ones of these have a long and a short leg, and are put with the long leg down for 7.50 and the short leg down for 6.00 (or perhaps more accurately the 5.5" and 5" rims respectively. Unless you have different ones to the ones I am familiar with, you probably have one the opposite way up to the other.

John

navigation2000
13th September 2008, 05:03 PM
I just went out and had another look, and the ones I have are different, 1 short and 1 long.

I suspect 1 is wrong, probably the short red one.

Regards,
Ross.

JDNSW
13th September 2008, 05:37 PM
Yes, I see. I think we will find that the ones I have are a later version (they came off an '81 S3) that fits both size wheel. You appear to have one each of the earlier ones; which is correct will depend on the size wheel you have (almost certainly the wider one) in which case the longer leg is the right one. The idea is that when the bit pressing on the wheel is pulled down tight, the other leg is supported by the base, so there is a straight pull on the bolt. I'll have to have a look round and see what I can find for comparison. All the bonnets I have do have the base, but I am not sure any of them have the fittings except the one on my 2a.

John

harry
13th September 2008, 05:56 PM
interested in what type of rivets failed -
were they solid rivets
or
'pop' rivets??
and as john said, the rivets are strong enough to do the job, the failure or rivets you are talking about are a maintenance issue with 30 year old rivets placed over a very hot engine whilst working and chilled many times over, add corrosion and dissimilar metals, what chance do they have ?
new rivets will do the job, but as you have bolted it ,no need.
have a look around and see if there are any other rivets missing heads or tails, it's not uncommon.

Rangier Rover
13th September 2008, 06:26 PM
This sounds normal to me. All our series 2s and 3s have done the same thing. Our country is rough so is expected. :)Just rivet it back on and will last for years
Tony

navigation2000
13th September 2008, 06:42 PM
interested in what type of rivets failed -
were they solid rivets
or
'pop' rivets??
and as john said, the rivets are strong enough to do the job, the failure or rivets you are talking about are a maintenance issue with 30 year old rivets placed over a very hot engine whilst working and chilled many times over, add corrosion and dissimilar metals, what chance do they have ?
new rivets will do the job, but as you have bolted it ,no need.
have a look around and see if there are any other rivets missing heads or tails, it's not uncommon.

Yes, I agree, the age of the rivets was likely a big factor as well as corrosion to a lesser degree.

The rivets themselves were just your normal aluminium outers with steel insert. Pretty sure they were factory.

I heard somewhere years ago that you use a certain type of rivet for attaching steel to a metal frames, but as this is aluminium to steel, I think the ones used were correct given the materials used, so yeah, I don't think they were the wrong ones. Further evidence to support the factory fitting is in that the paint under the wheel holder wasn't olive drab, but appeared to be a primer of some kind.

This vehicle has had just about every rivet, and every nut and bolt replaced prior to my buying it, so to find that wheel holder overlooked is a bit of a surprise. I should have known really, as all the other rivets are silver, yet the ones on the darn holder are painted, so yeah, slack me.

I've been all over that vehicle and doubt I'll find another issue like that arising anywhere else. Could just be the one area that was overlooked by the fellows who did this rebuild.

Looking back, I should have twigged that something wasn't right when I applied a bit of polish to the bonnet and could hear loose rivet noises, I tried to spin a few of the heads and they were all tight at that time, so the noises were obviously below the heads, likely at the joins to the substructure.

I should have investigated this further at the time, fortunately nothing came of it.

I also strongly suspect that the mis-match of the fasteners I used(supplied with vehicle) played a part here too, as the shorter "leg" red coloured fastener allows for increased upward pressure to be applied to the holder itself, and if you look at the design more closely, you can see how fatigue would be increased by this type of upward pressure, effectively tugging on the rivets.

All that aside, the mis-matched fasteners might have been a blessing really.

I had the wheel fastened down exactly as it appears in that picture, but now that I've bolted the holder down, I note that I don't have to tension the bolts down anywhere near as far as what they were before, and common sense now tells me that the holder was lifting when I was tightening it down last week, but as you can't see the darn thing, you just assume it's tensioning correctly.

I note too, that the bonnet shuts and locks down better now that I've bolted the holder down, as it's likely straightened it back up a bit. Those wheels weigh a bit, so it's a fair bet that flexing of the bonnet skin was occurring with the loose substructure.

Jeff
22nd September 2008, 05:14 PM
It might be that by tightening the bolts too tight you overstressed the rivets, as you say you are big on safety issues, but some people over torque bolts thinking more is better but it will stress the other bits.

I had a tyre slide off the bonnet years ago, but I didnt have a padlock pin to stop it when the bolts worked loose. Fortunately I wasnt going fast and stopped before it hit the road. It would be a bouncing missile in the suburbs.

Jeff

:rocket:

Dinty
22nd September 2008, 05:48 PM
G'day All, From your description 'The rivets themselves were just your normal aluminium outers with steel insert. Pretty sure they were factory.' that sounds like "pop rivets", unlike from the factory they are solid aluminium rivets, pop rivets do have corrosion problems after some time, I generally replace most pop rivets when I do a restoration as there is nothing worse than having the top coat of Deep Bronze Green and finding a rivet head has separated from the body:(:mad: cheers Dennis:angel:

JDNSW
22nd September 2008, 07:59 PM
G'day All, From your description 'The rivets themselves were just your normal aluminium outers with steel insert. Pretty sure they were factory.' that sounds like "pop rivets", unlike from the factory they are solid aluminium rivets, pop rivets do have corrosion problems after some time, I generally replace most pop rivets when I do a restoration as there is nothing worse than having the top coat of Deep Bronze Green and finding a rivet head has separated from the body:(:mad: cheers Dennis:angel:

Umm! Optional equipment parts book (2E 06) - part number 78248 - and the picture cannot be anything except a pop rivet!

Worth noting that the wheel mounting is an optional extra and most if not all would have been fitted by the dealer or distributor.

John

navigation2000
23rd September 2008, 10:56 AM
It might be that by tightening the bolts too tight you overstressed the rivets, as you say you are big on safety issues, but some people over torque bolts thinking more is better but it will stress the other bits.

I had a tyre slide off the bonnet years ago, but I didnt have a padlock pin to stop it when the bolts worked loose. Fortunately I wasnt going fast and stopped before it hit the road. It would be a bouncing missile in the suburbs.

Jeff

:rocket:


It might be that by tightening the bolts too tight you overstressed the rivets, as you say you are big on safety issues, but some people over torque bolts thinking more is better but it will stress the other bits.

I had a tyre slide off the bonnet years ago, but I didn't have a padlock pin to stop it when the bolts worked loose. Fortunately I wasn't going fast and stopped before it hit the road. It would be a bouncing missile in the suburbs.

Jeff

:rocket:

Hi Jeff,

Yes, it appears that when tension was applied, the holder was lifting at the points where the rivets were broken, but you can't see this happening as the wheel itself effectively shields all view. Yes, I agree, this lifting event would apply sideways pressure to the rivets themselves, probably hastening the incidence of failure. Had all the rivets been secure, then I guess applying pressure would have spread the load over the 9 rivets, not the 2-3 that appear to have been still doing a bit of what they were designed to do.

I never applied much pressure, as the bolts never seemed to tighten, so I just snugged them, sort of. But in hindsight, I did note that the wheel holder appeared to be drawing up slightly at the front as I was tensioning the bolts, I simply should have paid closer attention, but as this was the first time I'd ever done this kind of thing, I was entering uncharted waters.
Now that I know what to look for, it's not going to help me as I've gone to the next level and bolted the holder down.

The padlock pin is attached to the holder itself too, so that does nothing to ensure the wheel stays put in the event of a rivet failure.

Interesting to note that once I bolted the holder down, the bonnet now sits better than it did too, possibly a straightening effect has occurred with the substructure doing what it's supposed to now.

Dinty
23rd September 2008, 04:43 PM
G'day All, Yes JDNSW you are correct, even my S2A RPS shows a bloody pop rivet, but all of us old enough know that from the factory they came with solid round head rivets;) cheers Dennis:angel:
PS so the rot had set in way back then:(

Jeff
12th October 2008, 01:43 PM
Hi Jeff,


The padlock pin is attached to the holder itself too, so that does nothing to ensure the wheel stays put in the event of a rivet failure.


Yes, but mine came off because the bolts were loose, so the pin would help. I later fitted my own design pin made from a 3/4 in bolt from under the bonnet with a nut on top of the bonnet and the top machined down to fit the wheel stud hole and drilled for the padlock.

Jeff

:rocket:

ROBERT110763
27th December 2008, 06:40 PM
My staffy (dog) sits in the spare on the bonnet while travelling around, I have not had a problem with the rivets, & he weights 26 kg.

Cheers Bob

Lotz-A-Landies
27th December 2008, 08:20 PM
<snip>...The wheel holder had sheered all but 1 rivet and all just about come adrift.:o

I immediately took the wheel off and confirmed that all but 1 rivet had failed.

On closer inspection, I found that most had been broken for quite a while, and it's probable that only 2 or 3 rivets out of the 9 were ever doing their job.

How I failed to noticed this has rocked me, for I am usually quite an observant person, especially when it concerns safety. ...<snip>
See it pays to be a rivet counter! :D :D :D