Euro cruise disaster

Thanks for the comments guys and here are a few responses in no particular order.

The holes in the engine block are nearly 10mm deeper than the section of bolt that goes into it, so they can't bottom out.
I'm only going to lightly lube the threads before I refit the bolts. You should lube all threads into blind holes.
I'm using brand new bolts, albeit they have already been fitted once.
I blow the holes clean before refitting but its inevitable that some oil will go into the hole. I don't see this as being a problem.
I have access to calibrated tools.

The cylinder head bolts are 10mm dia standard metric course pitch 1.5mm. Grade 12.9, Max torque to this grade and size of bolt is 85NM. In my application they are tightened to less than half that ie 40NM, then a further 90' and then another 90'. Yield point on a 12.9 grade bolt is at around 85% of breaking load. (breaking load is just over 8 tonnes. Yes, 8 tonnes per bolt, uts is around 108kgs/mm2) The bolts will be in tension, obviously because that's how they work, but under this torque they wont stretch very much.

I can't understand why they use 12.9 grade bolts into aluminium as they are ultra hard and aluminium is very soft in comparison.
When the engine overheated, the cylinder head "bowed" upwards, which in turn pulled the bolts out of the threaded holes. The "bowing" and "pulling" is miniscule to the naked eye, but because the bolts are in under tension the forces are magnified.

I'm off to the pub now for a couple of Stella's and to watch the football.
 
Jack Ratt said:
Thanks for the comments guys and here are a few responses in no particular order.

The holes in the engine block are nearly 10mm deeper than the section of bolt that goes into it, so they can't bottom out.
I'm only going to lightly lube the threads before I refit the bolts. You should lube all threads into blind holes.
I'm using brand new bolts, albeit they have already been fitted once.
I blow the holes clean before refitting but its inevitable that some oil will go into the hole. I don't see this as being a problem.
I have access to calibrated tools.

The cylinder head bolts are 10mm dia standard metric course pitch 1.5mm. Grade 12.9, Max torque to this grade and size of bolt is 85NM. In my application they are tightened to less than half that ie 40NM, then a further 90' and then another 90'. Yield point on a 12.9 grade bolt is at around 85% of breaking load. (breaking load is just over 8 tonnes. Yes, 8 tonnes per bolt, uts is around 108kgs/mm2) The bolts will be in tension, obviously because that's how they work, but under this torque they wont stretch very much.

I can't understand why they use 12.9 grade bolts into aluminium as they are ultra hard and aluminium is very soft in comparison.
When the engine overheated, the cylinder head "bowed" upwards, which in turn pulled the bolts out of the threaded holes. The "bowing" and "pulling" is miniscule to the naked eye, but because the bolts are in under tension the forces are magnified.

I'm off to the pub now for a couple of Stella's and to watch the football.
Click to expand...

Thanks mate, I've been waiting patiently for this reply. Only possible fly in the ointment I could think of bearing in mind how you earn your living could have been an issue with the torque wrench and even that was a slim one.
Best of luck when you get back to it. Have a couple for me.

Tony.
 
Jack Ratt said:
Thanks for the comments guys and here are a few responses in no particular order.

The holes in the engine block are nearly 10mm deeper than the section of bolt that goes into it, so they can't bottom out.
I'm only going to lightly lube the threads before I refit the bolts. You should lube all threads into blind holes.
I'm using brand new bolts, albeit they have already been fitted once.
I blow the holes clean before refitting but its inevitable that some oil will go into the hole. I don't see this as being a problem.
I have access to calibrated tools.

The cylinder head bolts are 10mm dia standard metric course pitch 1.5mm. Grade 12.9, Max torque to this grade and size of bolt is 85NM. In my application they are tightened to less than half that ie 40NM, then a further 90' and then another 90'. Yield point on a 12.9 grade bolt is at around 85% of breaking load. (breaking load is just over 8 tonnes. Yes, 8 tonnes per bolt, uts is around 108kgs/mm2) The bolts will be in tension, obviously because that's how they work, but under this torque they wont stretch very much.

I can't understand why they use 12.9 grade bolts into aluminium as they are ultra hard and aluminium is very soft in comparison.
When the engine overheated, the cylinder head "bowed" upwards, which in turn pulled the bolts out of the threaded holes. The "bowing" and "pulling" is miniscule to the naked eye, but because the bolts are in under tension the forces are magnified.

I'm off to the pub now for a couple of Stella's and to watch the football.
Click to expand...
Good luck with it. I hope it goes smoothly...........................Frankie
 
t-tony said:
Have a couple for me.
Tony.
Click to expand...

Just got back to my digs, I've had 3 couples so I'll dedicate a couple to you =))

Both my torque wrenches were bought new and to honest have had very little use. I've never had them checked though so maybe I ought to. I work for Lloyds British Testing who were bought last year by Speedy Asset Services who also own Speedy Hire, and as such I have free access to all types of tools.
 
Jack Ratt said:
Just got back to my digs, I've had 3 couples so I'll dedicate a couple to you =))

Both my torque wrenches were bought new and to honest have had very little use. I've never had them checked though so maybe I ought to. I work for Lloyds British Testing who were bought last year by Speedy Asset Services who also own Speedy Hire, and as such I have free access to all types of tools.
Click to expand...

I have asked the guys who calibrate all our wrenches if they needed any adjustment and the stock reply is "Oh yeah they're always a little bit out" and to be honest I think these lads have to justify their days work at our branch or they wouldn't be needed. Night mate.

Tony.
 
I've had a bit of time in the garage today. I've mainly been cleaning the threads in the engine block, and getting the cylinder head ready to go back on.
I counted out the head bolts, 14 in total and then the head bolt washers, and only had 13 !!!! Thought I might have dropped one on the floor when I took the head off but I looked and couldn't find it.
I had to find it because I needed it for the rebuild. I have a couple of spares but I need to find the missing one.
There is a chance that it might still be in the cylinder head, hiding under the cam carriers. I looked with my endoscope but couldn't see it.

"B**llo+ks" !!!! I thought to myself, I've got to remove the cams from the head because I can't take the chance of it being in there and getting mangled in the valve springs when I start the car.

I was more than a bit p*****d off because I'd recently paid to have the head rebuilt, and cams removed, checked and refitted.

Anyway, out came the inlet cam and cam carrier.

20180127_131303.webp


No sign of it, so I refitted it and then removed the exhaust cam, ..............

......... and there it was nestling against one of the valve springs

20180127_134107.webp


You can see it between the 2 studs and between the valve springs.

So I got it out and then refitted the exhaust cam carrier and exhaust cam shaft.

So big relief all round.

I don't know how it came to get lodged in there. I must have lifted the head on it's side when I removed it from the car. You can see where it fits in the recessed hole on the other side of the valve spring. There's very little gap for it to go through, but "Sods Law" usually rules at times like this.

Hopefully I'll have another couple of hours on it tomorrow and we'll see what else I can f**k up =))
 
Jack Ratt said:
I've had a bit of time in the garage today. I've mainly been cleaning the threads in the engine block, and getting the cylinder head ready to go back on.
I counted out the head bolts, 14 in total and then the head bolt washers, and only had 13 !!!! Thought I might have dropped one on the floor when I took the head off but I looked and couldn't find it.
I had to find it because I needed it for the rebuild. I have a couple of spares but I need to find the missing one.
There is a chance that it might still be in the cylinder head, hiding under the cam carriers. I looked with my endoscope but couldn't see it.

"B**llo+ks" !!!! I thought to myself, I've got to remove the cams from the head because I can't take the chance of it being in there and getting mangled in the valve springs when I start the car.

I was more than a bit p*****d off because I'd recently paid to have the head rebuilt, and cams removed, checked and refitted.

Anyway, out came the inlet cam and cam carrier.

View attachment 72846

No sign of it, so I refitted it and then removed the exhaust cam, ..............

......... and there it was nestling against one of the valve springs

View attachment 72847

You can see it between the 2 studs and between the valve springs.

So I got it out and then refitted the exhaust cam carrier and exhaust cam shaft.

So big relief all round.

I don't know how it came to get lodged in there. I must have lifted the head on it's side when I removed it from the car. You can see where it fits in the recessed hole on the other side of the valve spring. There's very little gap for it to go through, but "Sods Law" usually rules at times like this.

Hopefully I'll have another couple of hours on it tomorrow and we'll see what else I can f**k up =))
Click to expand...
When I drop something, it usually dissapears off the face of the earth.............Frankie
 
Crikey just imagine if you didn't bother to look for it, doesn't bear thinking about :eek:.
Credit to you for perseverance :thumbsup:.
 
Jack Ratt said:
I've had a bit of time in the garage today. I've mainly been cleaning the threads in the engine block, and getting the cylinder head ready to go back on.
I counted out the head bolts, 14 in total and then the head bolt washers, and only had 13 !!!! Thought I might have dropped one on the floor when I took the head off but I looked and couldn't find it.
I had to find it because I needed it for the rebuild. I have a couple of spares but I need to find the missing one.
There is a chance that it might still be in the cylinder head, hiding under the cam carriers. I looked with my endoscope but couldn't see it.

"B**llo+ks" !!!! I thought to myself, I've got to remove the cams from the head because I can't take the chance of it being in there and getting mangled in the valve springs when I start the car.

I was more than a bit p*****d off because I'd recently paid to have the head rebuilt, and cams removed, checked and refitted.

Anyway, out came the inlet cam and cam carrier.

View attachment 72846

No sign of it, so I refitted it and then removed the exhaust cam, ..............

......... and there it was nestling against one of the valve springs

View attachment 72847

You can see it between the 2 studs and between the valve springs.

So I got it out and then refitted the exhaust cam carrier and exhaust cam shaft.

So big relief all round.

I don't know how it came to get lodged in there. I must have lifted the head on it's side when I removed it from the car. You can see where it fits in the recessed hole on the other side of the valve spring. There's very little gap for it to go through, but "Sods Law" usually rules at times like this.

Hopefully I'll have another couple of hours on it tomorrow and we'll see what else I can f**k up =))
Click to expand...

Mate, if it weren't for bad luck ..................... ;) Hope the bolts and threads work out ok.

Tony.
 
Glad you persevered with finding it, it's a worry when something like that happens. Good luck with the rest of it. :thumbsup:
 
Keep up the good work Jack cant wait to hear that you have it going again.

Geoff
 
Great read, pleased you found it, hope the rest of the rebuild goes without issue:thumbsup:
 
Good news you found it - anything left over I usually throw in the bin!!=))=))
 
It's a good thing you didn't just start reinstalling everything only to find out as you neared the end that you were short that one washer. Pull it all apart again to go looking for it! Nice detective work in finding it and lucky you did! Looking forward to hearing that engine running strong again! JIM
 
Good catch in finding the washer before it did any damage.
 
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