further on from a thread the other week, concerning tightening down head bolts ( the thread was about bolts snapping, not for fear of wanting to do the same, i have seen a VW "expert" so it the other week ) but keep them dry as they are supplied in the bag or very lightly oil them? seemed to have a mixed bag of opinions with it.
Personally...make sure holes in the head are blown out with air,and leave the bolts dry Never had a problem so far...touch wood Neil.
not bad twenty minutes and two opposite answers last time the bolts were supplied oiled up, this time i have them direct from the shop so they are dry, bolt holes are nice and clean.
When you buy them in sets most manufacturers supply copper slip to lube the bolts, its not just to look at Im sure Ive seen somewhere (possible autodata tech book) where it says before every torque setting to lightly oil the bolt threads
haven't looked in the box properly yet its a bit like christmas here last set of bolts came via the garage, who had applied the copper slip to them, Crispy 8V (vw tech) who installed them didn't say anything about them being a bad idea like that.
always always always lube headbolts before assembly. when dry they can bind slightly when tightening up, thus giving a false torque reading, and thereby not being tight enough.....plus there is the chance they will either snap (small chance) or go plastic (quite probable) when being tightened.
I was the one that kept snapping them Final time i did them i'v used VERY good quality torque wrench and just used bolts as they came(appeared to be oily) and all was well
i snapped them too, was my fault though, some come greased up and some dont, double check the holes are clean and very lightly oil the bolts, will torque up and remain fine.
I can't remember where I read it, but it was a head gasket suppliers website, and they had a tech-tips section which made some interesting reading. Anyhow, they did a bit on correctly installing head bolts, and suggested lightly lubricating the threaded portion, and also between the bolt-head and captive washer, but not beneath the washer. Damn, wish I'd made a note of it.. The tech tips section on the ARP website has got loads of technogobble for all you boffins.
I should say...If i bought head bolts that came with a specific lube/copper slip id use it But they never have,so i never erm have Neil.
I have a set of head bolts for an 8v at home, I think they are febi. The sticker on the box says to lightly oil before assembly and they are already slightly oily. The torque seqence on the box is different to haynes aswell. It says two torque stages, then back off 90, then I think its tighten 90 degrees twice (or tighnen 90 then 180 degrees). Should I go with that or haynes?
for the 20v its 40Nm then 90 degrees, then another 90 degrees. see if engineering here have any spare copper slip.
NEVER copper slip head bolt in - unless you intend to pull the engine appart in 10k miles due to gasket failure! I've seen this so many times. Who is it telling people to lube head bolts?!? Don't do it - ever! When you buy them, they already have the thinest of carbon lube on them, which is more than enough. Make sure the bolt holes are clean and dry and there is no swarf in them. If you copper slip them, they hyraulic - you then get a false torque reading - simple as that.
