I need to replace my lower strut bolts as they are rounded and will have to be cut out when I replace my struts. I need to know what size and specification these bolts are as I have found some replacements online but they are charging £3.50 a bolt and £0.80 a nut and that is not something I am paying for nuts and bolts. What size are the bolts so I can buy generic high tensile ones instead of "Fiat official"
Technical Lower Strut Bolts
- Thread starter hazemaker
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Technical Lower Strut Bolts
Now don't shoot me down in flames & I'm certainly not judging you in any way. Possibly we are at different ends here, but for the correct items in question, I certainly do not think that is too much money.
Off topic & certainly not aimed at anyone in particular, but I'm regularly a bit surprised how some will spend shed loads on fancy add ons & go faster stripes & the likes for their vehicle & skimp on the very things that are important such as serviceable parts. Just my thoughts...
Off topic & certainly not aimed at anyone in particular, but I'm regularly a bit surprised how some will spend shed loads on fancy add ons & go faster stripes & the likes for their vehicle & skimp on the very things that are important such as serviceable parts. Just my thoughts...
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i think its 15 size bolt and 17 size nut
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Like I said in your other thread, I posted all the info on the bolts:
https://www.fiatforum.com/punto-ii/436392-hub-suspension-bolts-strength-class.html
They are expensive because:
1. They are galvanised (not zinc plated)
2. They are fine pitch, i.e. Not (as) mass market
3. The bolt has a custom lead in
4. The nut has an integrated cup washer
5. Both the nut and bolt are higher strength class
As said above, it's not really much to pay for this kind of bolt. You definitely don't want the wheel to pancake...
https://www.fiatforum.com/punto-ii/436392-hub-suspension-bolts-strength-class.html
They are expensive because:
1. They are galvanised (not zinc plated)
2. They are fine pitch, i.e. Not (as) mass market
3. The bolt has a custom lead in
4. The nut has an integrated cup washer
5. Both the nut and bolt are higher strength class
As said above, it's not really much to pay for this kind of bolt. You definitely don't want the wheel to pancake...
They are likely to be grade 10 bolts and nuts, so are more expensive than 'standard' 8.8 bolts.
Most general bolts are 8.8, usually cast onto the head of the bolt. For specific tasks, a higher tensile bolt is specified, and the head will show a '10' on it. The nut needs to be the same grade. If you torque up a 8.8 to the tension specified for a 10 you are likely to overstress it, and cause it to fail. Similarly, if you use an 8.8 where a 10 is specified, it is being subjected to higher stresses than its design strength.
What price your life, or anyone you hit when they fail? Dig deep into those pockets and get the right ones.
Most general bolts are 8.8, usually cast onto the head of the bolt. For specific tasks, a higher tensile bolt is specified, and the head will show a '10' on it. The nut needs to be the same grade. If you torque up a 8.8 to the tension specified for a 10 you are likely to overstress it, and cause it to fail. Similarly, if you use an 8.8 where a 10 is specified, it is being subjected to higher stresses than its design strength.
What price your life, or anyone you hit when they fail? Dig deep into those pockets and get the right ones.
Ignore my ignorance, I'm new to working on my own car and am still learning. Regarding your other forum post that you've linked would these bolts be suitable do you think?
ebay.co.uk/itm/METRIC-FINE-PITCH-HT-BOLT-M10-x-70mm-x-1-25mm-NYLOC-NUT-CP108A-x-5-OF-EACH-/360679101039
Or these?
ukbolt.co.uk/m10-x-125-x-20-30-40-50-60-70-hexagon-head-flange-fine-thread-bolts-black-109---231821112751-67288-p.asp
(You'll have to add the www. in yourself as I am not allowed to post URL's until I have made 5 posts :bang: )
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The first link do not mention the grade, so will almost certainly be 8.8, or worse, so NO.
The second link are 10.9 grade, but you would need to determine if the bolt length was correct, as you need the strut to sit on bolt shank, not thread. You'd need 10.9 grade nuts too.
Go buy new OE ones and don't compromise yours, and others' safety for a few pence.
Out of all the times I've changed struts in the last 40 yrs or so I think I have only had to cut them off about twice, clean the threads properly, plenty of oil and they'll open. Yes sometimes I put new nyloc nuts on but wouldn't dream of going to a main dealer for things like this. Any good engineering suppliers will have the necessary grade. The other things is people try doing these jobs with half hearted tools, you need decent stuff, not cheap Chinese sh//t. If they're stiff a decent 3/4 drive socket will soon sort them.
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First time i tackled thd job i didnt have correct tools
When i tackled on the current car
A good pre-soak helped loads along with a 1/2 breaker bar
Still needed a good wack and turn to free bolts
However mine were wire wheeled clean and copper slipped to the eye balls and upon removal now its pretty easy
Ziggy
As the Op said they are rounded, obviously from bad tools, a decent socket set, wrenches, screwdrivers and a multi meter are the basics. Takes time to build up a decent set but well worth the investment.
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I think what is easy for you is going to be difficult for the op; you're much more experienced. Lying on your back (in a puddle if you're really unlucky
) trying to fight these off is enough to put you off for life....I would pay the money to avoid doing that, and I recommend to the op he does the same.
The Op said he's going to have to cut them off anyway! That's awkward enough. To get at then with a grinder or hacksaw or even a nut splitter is difficult. Its amazing how simple a job can be with the right tools and a bit of knowledge, Perhaps they might open easy enough with a good wire brushing, plenty of penetrating oil and if needs be a vice grip on the rounded nut and a decent socket on the bolt. Don't forget if the were rounded trying to take them off with a bad/wrong socket, it will do the same tightening new ones up! Don't forget people post here for help and advice, if they choose to ignore any help advice given that's their prerogative.
To be fair to the OP, which isn't something I'm known for, these things rust like crazy for fun and usually round off anyway even using good tools unless Snap-on isn't good enough for you? The other option is to get the old ones out then take them to a fastener specialist and match them up. The one I use charges pence for stuff like that.
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No, that's part of the thread designator (approximately 10mm outer diameter). Full details are in the ISO metric thread designation.
Strength class relates to the material, and is independent of thread type.
Strength class relates to the material, and is independent of thread type.
Isnt the M10 the grade?
METRIC FINE PITCH HT BOLT M10 x 70mm x 1.25mm
M10 is the thread diameter and metric.
70mm is the overall bolt length, from the underside of the head to the bolt end.
1.25mm is the thread pitch, which for an M10 is a fine pitch. The standard for M10 is 1.5mm.
These guys explain a lot if you browse their website.
http://www.westfieldfasteners.co.uk/Ref_Strength_Spec.html
However, they do not appear to do fine pitch bolts, but do offer 10.9 grade standard pitch.
Namrick are another good source and do offer fine pitch, but only offer standard 8.8 grade. So far, I have not found a source for fine pitch 10.9, but haven't looked too hard, as I don't require any right now.
We have an amazing place here, you can go in a buy one nut or bolt if you want, all sizes, grades, sure there are places like this in UK as well. http://www.hassetts.ie/
I've done 6 Punto struts in the last few months and opened all of them no problem, I don't have Snap-on BTW,
. Draper and Magnusson is what I've used, I always clean off the threads and if possible give them a good soaking beforehand. You can have all the Snap-on, Brittool and Gedore tools money can buy but not worth a monkeys if you can't use them.
