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Are You Using Sub Standard Bolts In Your Engine ?


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#1 MRA

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Posted 31 October 2010 - 07:35 AM

On the subject of fixings...........

Bolts

We have noticed an increasing trend for certain suppliers to sell a centre main strap with "high tensile" bolts..... however these HT bolts are not of a sufficient tensile level to even be close to the original items used to hold your crank in to the block.

You should be using an SAE grade 8 bolt not an ISO 8.8 bolt

A rough guide is ISO 8.8 is SAE 5 which is about as low as it goes in HT bolts.....

The main cap bolts as supplied by Austin, Morris, Leyland, Rover, etc are SAE 8 which is about the same as ISO 13.9

The SAE 8 bolt is recognised by the 6 lines formed in to the top of the head of the bolt, these bolts would also come with a certificate of conformity, ask your supplier for a copy, if they can't supply one then is it worth using the bolts ?

How much did your engine cost you ? don't be forced to use substandard parts just because your supplier hasn't the knowledge or experience to know the difference yo uwill be risking your engine and possibly your gearbox if it all goes wrong.

#2 AndyMiniMad.

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Posted 31 October 2010 - 07:52 AM

Ive just had to strip my engine ,AGAIN, for other reasons. but the bolts that were supplied with my center main strap(Jonspeed) dont have these lines on them. I phoned them up at the time and asked and they said they were fine and to the correct tensile strength.. Im not so sure now?? Is this something you could supply Martin??? Er sorry for the blatent shopping on the forum!!!

#3 Dan

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Posted 31 October 2010 - 07:59 AM

If bolts are supposed to be a certain grade but aren't marked, don't use them. Any nut and bolt factor can get you properly graded, marked and even tested and proofed bolts if you need so why risk it? Jonspeed's bolts may well be up to scratch but if they are and aren't marked they are getting them from a cheap source. From a supplier who has no reliable way to tell the difference between the bolts they are sending out to customers from the thousands of types they produce. In this case Jonspeed have no way of knowing if what has been supplied to them is what they ordered.

#4 mike.

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Posted 31 October 2010 - 08:03 AM

I suffered this problem with a centre main strap from morspeed. The strap they provided was quite thick and the bolts were poor quality; this meant they didn't screw into the block far enough.

When I started building the engine, I torqued up the first bolt on the centre main and it stripped the thread out of the block. It wasn't until afterwards when I inspected the bolts that I realised they only went into about 5mm of thread!

The hassle this caused me was just unreal and I ended up buying some super strong, longer bolts from America. I had to have the block machined, the bolts machined and the strap itself slimmed down!

Heres the thread on problem. You'll see how much trouble it caused me: Link

#5 AndyMiniMad.

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Posted 31 October 2010 - 08:15 AM

I found a picture in my build thread... What do you think????

Posted Image

Posted Image

Would these bolts, if incorrect, Have caused any damage??? Im off to the garage to check the throwout on the crank!!!

#6 mini13

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Posted 31 October 2010 - 08:53 AM

I "think" the are 5 stripe bolts (hard to tell from the pic) making them grade 7,


http://www.americanf...kings_steel.asp


Personally I always use studs for the mains, but thats just me,

There is a chap in the US that does really high grade mains bolts (including the long ones for centre main straps) for the A series at a really good price, also hos high grade gearbox to block fastening kits. He can be contacted through Turbominis or minimania on username Turbodave.

#7 MRA

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Posted 31 October 2010 - 10:23 AM

Ive just had to strip my engine ,AGAIN, for other reasons. but the bolts that were supplied with my center main strap(Jonspeed) dont have these lines on them. I phoned them up at the time and asked and they said they were fine and to the correct tensile strength.. Im not so sure now?? Is this something you could supply Martin??? Er sorry for the blatent shopping on the forum!!!



Yes Andy we have the correct SAE grade 8 bolts in stock and at the correct length. However this topic was to raise awareness of the situation.

#8 AndyMiniMad.

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Posted 31 October 2010 - 12:38 PM

Ive just had to strip my engine ,AGAIN, for other reasons. but the bolts that were supplied with my center main strap(Jonspeed) dont have these lines on them. I phoned them up at the time and asked and they said they were fine and to the correct tensile strength.. Im not so sure now?? Is this something you could supply Martin??? Er sorry for the blatent shopping on the forum!!!



Yes Andy we have the correct SAE grade 8 bolts in stock and at the correct length. However this topic was to raise awareness of the situation.

Ok Martin, Ill call you tomorrow.
Im really pleased you started this topic today. Perfect timing..I hope many other people find it as usefull as I have.

#9 Ethel

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Posted 31 October 2010 - 01:33 PM

It looks like your bolts are plated Andy, that would be unusual for high tensile bolts. You can see the 6 "spokes" on the original cap bolts in your piccy, as Martin explained. The markings should be the same pattern but probably not as deep as the originals. If you use washers they need to be of the same grade.

#10 AndyMiniMad.

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Posted 31 October 2010 - 02:59 PM

Been out and checked the crank with my DTI guage. Its fine thank god!!! The bolts have three lines on the head pointing to 12 o.clock, 4 oclock and 8 o'clock. They are also marked F B S.
The closest i could find on the chart posted by Mini13 is the grade 5 bolt. Im guessing this is not strong enough so will speak to Martin tomorow.

#11 Sprocket

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Posted 05 November 2010 - 10:06 PM

I feel certain Moral Rights have been abused in this topic. This is nothing new and has been discussed on Turbo Minis in a topic that I Authered, deliberated and participated as far back as 2007, highliting the very issue of supply of sub standard bolts. Do not get me wrong, I am not suggesting that I was the first person in the world to discover this, but more that there was nothing to document it before the subject arose on Turbo Minis. This information here appears as if it is the work of MRA Minis, when infact I and many others have discussed this in great depth on Turbo Minis to the point that Minispares have since changed the bolts they use in their strap and four bolt center main kits. MRA Minis are not the only company selling the correct bolts, as could be easily assumed, and more likely than not, MRA Minis changed their grade of bolts as a direct result of the initial topic over on Turbo Minis, yet there has been no aknowledgement of this fact.

#12 danrock101

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Posted 05 November 2010 - 10:22 PM

I have seen the same thing going on, I think I saw some coilovers with the SS bolts to attach them to the brackets and have seen these type of bolts/studs for sale, advertised for things they shouldn't be used for. I almost thought about saying something on here myself, as I wasn't actually 100% sure as I had seen it plenty of times and not heard any mentioning of it, nothing wrong with bringing it up, I haven't even got a turbo minis account (yet :D ) So thanks MRA for bringing it up

#13 Sprocket

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Posted 05 November 2010 - 10:26 PM

The point I am trying to make is that some one is clearly selling something using the informtion generated by others, without any aknowledgement. I have no argument with the information being put out, but there needs to be some aknowledgements somewere surely

#14 danrock101

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Posted 05 November 2010 - 10:29 PM

You're saying MRA stole your information to post it on here so he can sell some bolts?

#15 danrock101

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Posted 05 November 2010 - 10:31 PM

I'm confused, maybe if you made your topic on the same forum, but you made a topic on a forum about these bolts then someone 3 years later, on a different makes a topic about the same problem, that doesn't mean he stole your information, was the info copy'd and pasted?

Edited by danrock101, 05 November 2010 - 10:32 PM.





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