Hei.
Will I need new bolts (10 of them) when changing the head gasket? And why / why not.
Morten.
Will I need new bolts (10 of them) when changing the head gasket? And why / why not.
Morten.
Technical Cylinder head bolts.
- Thread starter Morty Mort
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Technical Cylinder head bolts.
Morty Mort said:
When i changed the head gasket on mine i used the same head bolts, and the engine has done a good 6k miles since and still no problems
OK Mort, a very good question (I would have expected nothing less from you! 
)
You can get away with re-using the head bolts, but only a few times. Personally, I would only re-use once, and even then only if I was trying to do the job cheaply.
When you try the angle-tightening method, you'll find out why. Don't forget to oil the bolts with engine oil and allow to drain for 30 minutes. Then you tighten all bolts to the first torque figure (e.g. 20Nm though this might not be correct!) and then to the second torque figure (40Nm). Then, you have to turn each bolt through 90 degrees, and then each bolt through a further 90 degrees (check your Haynes manual for those torque figures, I can't quite remember and don't have the book handy).
As you tighten the bolts through 90 degrees (I use a marker pen to draw a line across the bolt head, makes it easy to see when you have turned far enough) you will find the torque increases greatly, meaning you will really struggle for the last 90 degrees...
...unless you use new head bolts, in which case you will be able to tighten them easily. The bolt stretches by a defined amount as you tighten. This is to provide an even clamping force and eliminates the need to re-tighten the bolts after (say) 1000km like you used to have to do with engines from the '70s. Stretch bolts are very much an 80s thing, because they made engines easier and cheaper to assemble.
It doesn't take much brain-power to realise that once the bolt has 'stretched', it's not going to stretch the same again, which is why the bolts are harder to tighten the next time.
I suffered a blown head gasket once on my high-compression modified engine(lost compression between two cylinders), and used the same type of normal gasket to replace it. I never had any more problems, I like to think because the second time I used new bolts.
Get a price for the new bolts, and if they're cheaper than the head gasket was, then I say you should replace them
By the way, I also agree with Luke - my Uno 60 has re-used bolts and it's doing fine, so did another Uno 70 that I worked on years ago... so it's up to you.
If you do decide to re-use the bolts, and you find the last 90-degrees to be a struggle, my personal tip: set your pre-set torque wrench to about the same figure used for the old-style engines (not stretch bolts) of 10 m.k.g., and use this as an upper limit - to avoid damaging threads.
Thanks,
-Alex
)You can get away with re-using the head bolts, but only a few times. Personally, I would only re-use once, and even then only if I was trying to do the job cheaply.
When you try the angle-tightening method, you'll find out why. Don't forget to oil the bolts with engine oil and allow to drain for 30 minutes. Then you tighten all bolts to the first torque figure (e.g. 20Nm though this might not be correct!) and then to the second torque figure (40Nm). Then, you have to turn each bolt through 90 degrees, and then each bolt through a further 90 degrees (check your Haynes manual for those torque figures, I can't quite remember and don't have the book handy).
As you tighten the bolts through 90 degrees (I use a marker pen to draw a line across the bolt head, makes it easy to see when you have turned far enough) you will find the torque increases greatly, meaning you will really struggle for the last 90 degrees...
...unless you use new head bolts, in which case you will be able to tighten them easily. The bolt stretches by a defined amount as you tighten. This is to provide an even clamping force and eliminates the need to re-tighten the bolts after (say) 1000km like you used to have to do with engines from the '70s. Stretch bolts are very much an 80s thing, because they made engines easier and cheaper to assemble.
It doesn't take much brain-power to realise that once the bolt has 'stretched', it's not going to stretch the same again, which is why the bolts are harder to tighten the next time.
I suffered a blown head gasket once on my high-compression modified engine(lost compression between two cylinders), and used the same type of normal gasket to replace it. I never had any more problems, I like to think because the second time I used new bolts.
Get a price for the new bolts, and if they're cheaper than the head gasket was, then I say you should replace them
By the way, I also agree with Luke - my Uno 60 has re-used bolts and it's doing fine, so did another Uno 70 that I worked on years ago... so it's up to you.
If you do decide to re-use the bolts, and you find the last 90-degrees to be a struggle, my personal tip: set your pre-set torque wrench to about the same figure used for the old-style engines (not stretch bolts) of 10 m.k.g., and use this as an upper limit - to avoid damaging threads.
Thanks,
-Alex
Last edited:
OP
OP
Thanks for the reply Alex.
You propably remember the thread about the compression failure. I re-used the bolts that time, and struggled very hard to do the angle-tightening you mentioned. I can not remember the correct Nm amount etc. either, but I´ll look into Hayne´s manual again.
The reason I ask, is wether or not to use them the 3rd time. I´ve ordered a new set now anyway, after reading your post. The worst that can happen is that a bolt tears IN the block. It can be fixed, but not with any of my tools.
I´ve noticed a little loss of coolant lately, in addition to mayo in the filler cap, and white smoke through the exhaust. So I suspect I´ve done something wrong when bolting the engine back. It has never overheated, so I don´t think the head is warped.
So it is project sunday if I get all the parts. Is there any interest amongst people if I take pictures and post the procedure?
Morten.
You propably remember the thread about the compression failure. I re-used the bolts that time, and struggled very hard to do the angle-tightening you mentioned. I can not remember the correct Nm amount etc. either, but I´ll look into Hayne´s manual again.
The reason I ask, is wether or not to use them the 3rd time. I´ve ordered a new set now anyway, after reading your post. The worst that can happen is that a bolt tears IN the block. It can be fixed, but not with any of my tools.
I´ve noticed a little loss of coolant lately, in addition to mayo in the filler cap, and white smoke through the exhaust. So I suspect I´ve done something wrong when bolting the engine back. It has never overheated, so I don´t think the head is warped.
So it is project sunday if I get all the parts. Is there any interest amongst people if I take pictures and post the procedure?
Morten.
Cylinder head bolts
Amazing argument their alexGS From you, I’d expect no less.
Did you sell your 60 on Saturday?
_Louie Bee__on 1T?
Go for It! __OnIt_
YER! Would be priceless and (hopfully) make this thread a sticky!
Amazing argument their alexGS
From you, I’d expect no less.
Morty Mort said:
_on 1T?
YER! Would be priceless and (hopfully) make this thread a sticky!
Last edited:
sterryroad
New member
A bit late on this one, but I'd change the bolts for the sake of a tenner or less. I broke a few bolts in the past and it's a pain in the arse to have to loosen all the bolts again and start over. And you can be sure the job is done properly - torque wrench from Argos at £14.99 does the job too.
Cylinder head bolts?
Hi sterryroad There are some settings too low for the Argos wrench, I got a - SEALEY STW1011 Torque Wrench Micrometer for £32.95. (inc vat + delivery) It has a better range of 7-112Nm/5-83lb.ft, which helped when I did my cam cover gasket lol.
Hei Morten, How are the Head Gasket picks progressing?
Kind Regards,
Hi sterryroad
I had a look around before I bought a toque wrench.sterryroad said:
There are some settings too low for the Argos wrench, I got a - SEALEY STW1011 Torque Wrench Micrometer for £32.95. (inc vat + delivery) It has a better range of 7-112Nm/5-83lb.ft, which helped when I did my cam cover gasket lol.Hei Morten, How are the Head Gasket picks progressing?
Kind Regards,
sterryroad
New member
Yeah, better off buying a decent one without doubt. I use mine from Argos for all sorts of jobs - great for loosening hub nuts when replacing wheel bearings. So I've had my money's worth and it's still going.
OP
OP
Gasket change pics is still a project.
This is the story. My brother (who is the real owner of the Ritmo Abarth 130TC) has a contact through work that let them use their garage on special occations. The moron who used it before us managed to go on holiday WITH the ONLY key. Anyway, weather is clearing up here at the time, snow is melting, and squirrels run across the streets and gets killed.
True signs of SPRING. So maybe it can be done outdoors soon.
So - when it gets done, I will make a photo documentation as good as possible. Of tools needed, precautions etc. But remember, I´m nothing but an amateur - have never touched a car mechanically before we bought the Uno.
Morten.
This is the story. My brother (who is the real owner of the Ritmo Abarth 130TC) has a contact through work that let them use their garage on special occations. The moron who used it before us managed to go on holiday WITH the ONLY key. Anyway, weather is clearing up here at the time, snow is melting, and squirrels run across the streets and gets killed.
True signs of SPRING. So maybe it can be done outdoors soon.
So - when it gets done, I will make a photo documentation as good as possible. Of tools needed, precautions etc. But remember, I´m nothing but an amateur - have never touched a car mechanically before we bought the Uno.
Morten.
Hi Morten,
All sounds Good (apart from squirrels and key lol)
It’s very encouraging as I’m an amateur (hobby) mechanic too.
Can’t wait for pictures! Good Luck and let us know if any problems, of if your after info from my porter manual
Kind Regards,
All sounds Good (apart from squirrels and key lol) It’s very encouraging as I’m an amateur (hobby) mechanic too. Can’t wait for pictures! Good Luck and let us know if any problems, of if your after info from my porter manual Kind Regards,
