What happens next after I break the rule?

[Dubwana]

On a 1.6D cylinder head the warnings are very clear... 12 point cylinder head stretch bolts MUST be replaced. So the guy that wrote that didn't live in Africa and has decent VW dealer around the corner. So far and good. They aren't available here we've got the head on, its fully torqued with the extra half turn. After we put the engine in and get it running do we do the extra 1/4 then the extra 1/4 after a 1000 miles or not or do we quit turning while the going is good? Now I know most of you good people will of put in new bolts as the book said. I can't get them. I can't wait till I get them. I'm asking the chancers out there... who has done put a head on with old bolts, how tight did you go, and what problems did you get, if any. Many thanks, Dubwana

[ermie571]

Dubwana...

if they are availabel here..I will send them to you so you don't have to chance it for too long!

Are they expensive??

Em
x

[Dubwana]

Em... Thank you most kindly for your offer, it is kind and thoughtful, however... they would be nicked on the way. Almost guaranteed anything useful almost invariably is. However, please retain you kindness. It is all to rare in this world.

Best regards,

Dubwana

[Oldiebut goodie]

I seem to recollect that you were playing with two engines - do you have the hex head bolts on the other engine. Just a thought.

[Dubwana]

Thanks, I thought about that too but they were 12 point all round

[Red Westie]

I can't remember automatically replacing head bolts being a VW poilcy, when these things were new the decision to replace the bolts was made using two criteria.
Condition: are the bolts pitted/corroded etc
Length: have the bolts stretched beyond their stretch limit (there will be a max length limit somewhere in the specs for head bolts)

If they are in good condition and within stretch limit they VW say you can re-use them.
Replacement has become the normal only because of the relatively inexpensive nature of the parts.
As for Toque/tightening down sequence....just follow the VW guidelines.
Martin

[Mr Bean]

I can't remember automatically replacing head bolts being a VW poilcy, when these things were new the decision to replace the bolts was made using two criteria.
Condition: are the bolts pitted/corroded etc
Length: have the bolts stretched beyond their stretch limit (there will be a max length limit somewhere in the specs for head bolts)

If they are in good condition and within stretch limit they VW say you can re-use them.
Replacement has become the normal only because of the relatively inexpensive nature of the parts.
As for Toque/tightening down sequence....just follow the VW guidelines.
Martin

Yes I agree but most people I know actually misuse the torque wrench and overtighten. I guess this is either because they feel the need to make sure it is tight enough (torque wrenches almost always give a lower force than one would employ if applied empirically i.e. by guesswork) and they tend to give it another tweak after it has clicked/broken just to be sure. I would suggest that using old bolts you do not tweak it and maybe get to the final figure in more steps than the manual describes. Engineering is only black and white when the ignorant and pedantic get involved.
Cheers
Wolfie

[dugcati]

Engineering is only black and white when the ignorant and pedantic get involved.

I love that one!

[Dubwana]

Thanks for the observations. I too think that is a great quote. I am ignorent but learning. We decided to go with the "they look good we'll use them" and they have done just fine for the three weeks that I ran the vehicle. Now on vacation in Canada, decided Africa to North America was too far and took the plane but will keep on driving when I get back. Any ideas on how to get the max length for stretch bolts specs. Could be useful in the future. NOt that I plan to blow my engine again but there again...

[The Reverend Pimp Daddy]

buy some new ones wilst you are in Canada

[bigherb]

Yes i agree buy them in Canada. VW never gave a length for the bolts just said they should always be renewed, There is a rolled in groove in the bolt which stretches when tightend but stays stretched once released hence the non reusable bolts.

[Red Westie]

OK...did a bit of digging and found this on a CS (non turbo Diesel)



Martin

[andysimpson]

In and ideal world they should always be replaced but not that important on a standard engine especially a non turbo engine. Bolts should never be retorqued at xxx mileage, vw had a re think on this after loads of ones that had been retorqued had gasket problems and ones that were left alone were fine.