tightening 16v head

so i know the " torque" and tightening sequence, but is there anything else i should do before putting gasket on and torquing, should i use sand paper for block cleaning?

also that 90 degree torque, does it rly have to be tightened like that or is that just exaggerating

at what nm should i set my torque wrench

How long is a piece of string ?
If you have removed all traces of the previous gasket and the head hasn't warped it should be ok. When you start attacking the surfaces you risk un-flattening them. I've seen some go at them with wire brushes on a drill. That quickly feathers off the edges and the gasket gets less of a bite from the head. Mostly I use solvent and a soft scraper and patience.
The 90/90 does the business. The 20/30 Nm is just snuggling up before the main event.
The point about torque setting is to stretch the bolt by enough so that no matter what happens heat and load wise the joint is never loose. The problem with a torque wrench is that it can't tell the difference between stretching the bolt and a rusty thread. Angle tightening is different. If the bolt goes 90 it stretches by 1/4 of the thread pitch no matter what torque was required to do it.
And check the gasket is actually in there and the right way around

What application is this?

i got the head resurfaced as it was bent a little, also got new head bolts
previous head bolts were tightened down so hard i had to drill one, thats cuz they didnt use 90-90 method?
thats autodata

Brendan W said:

The point about torque setting is to stretch the bolt by enough so that no matter what happens heat and load wise the joint is never loose. The problem with a torque wrench is that it can't tell the difference between stretching the bolt and a rusty thread. Angle tightening is different. If the bolt goes 90 it stretches by 1/4 of the thread pitch no matter what torque was required to do it.

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Seems to me the initial tightening has to nip up the gasket to the required degree with the bolt rotating without excessive friction and be already at the right tension for the final stretching. Redoing the gasket must be a bit hit and miss??

after 3 months im gonna finally tighten this head
how smooth should engine block be? that i cant feel anything if i go through it with my hand?

what nm should i set my torque wrench for final tightening? cuz that autodata 90 degrees seems strange

Smooth as you can. Remove all traces of the of gasket. Lay a straight edge on it and if your thinnest feeler blade won't go you're good. Go easy on the scraping. Metal tools will leave gouges. I use acetone or mek and kerosene and a plastic scraper or a stanley blade.
Modern head gaskets have sealer in them so using additional sealer or the traditional aluminium paint can work against you if it reacts badly with the gasket. I still use the Al paint on bike base gaskets if the surface has a few too many nicks.
If a head bolt is badly corroded you can set any torque you want and the nut won't turn enough to stretch it the required amount. The headbolt is really a bungee keeping the head down and has to be stretched. By turning the nut 90 degrees you are sure that the bolt has been pulled up by a quarter of the thread pitch ( leaving out gasket compression). You won't need the torque spanner to do it, Just use a socket and bar. I don't use the angle guage either. 90 degrees or quarter turn is easy to mark out with a bit of wax pencil or by eye.

i got new set of head bolts, by saying i will need to use bar and socket, that means its gonna get torqued quite hard, what if i dont torque one or few bolts as much as the other, will i have to strip it again?

No harder than pulling 90 degrees with a torque spanner. I use the bar so I don't lose track of how far through the 90 I have gone. A ratchet would lose track if you accidentally went back for a second bite. The torques will be different but that's the whole point of angle tightening. It stretches all the bolts the same amount. Torque spanner only does that if all the threads on the bolts and nuts are identical and the friction between the nuts and the seats are identical. That's why angle tightening is better.
The gasket doesn't care about torque, all it sees is how much is the bolt is stretched.

scared i will overtighten one bolt and gonna have to start from scratch

did you mean mark bolt head like this

i guess this is how its supposed to go on, right?, can see all the holes through hg

do i need to lubricate head bolts?

flisko said:

scared i will overtighten one bolt and gonna have to start from scratch

did you mean mark bolt head like this

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Mark the start position of the bar or ratchet or torque spanner and then mark 1/4 turn from it. I do it by eye.

flisko said:

i guess this is how its supposed to go on, right?, can see all the holes through hg

Click to expand...

Never done a 16V but the tab sticking out at the top left looks good. Least that's the way the 8V sits.

https://www.fiatforum.com/punto-ii/430293-head-bolts-lube-dry.html

lube them with fresh engine oil?

Hi,
Gasket position looks good to me. On the torque setting, the only figure you need is 20nm. you do all the bolts up in sequence ending up with 20nm (I'd let it sit for 10 minutes and then re-check the 20nm. The final tighten is the 90 degrees. This is simply turning each bolt through 90 degrees as Brendan says it's easy to do tihs with a bar. You can also use one of these
https://www.machinemart.co.uk/p/laser-2611-1-2-drive-torque-angle-gauge/
But you only really need these for angles other than 90 degrees. You do not need a proqure wrench for this final tightning, but if you do, ignore any reading.
The advange of the 90 degree tightn is that it is indepedent of the friction from the threads and head of the bolt. This gives a more consistent stretch of the bolt and reduces the chance of fatigue failure.

HTH,
Robert G8RPI.

If you have new bolts the threads will be clean, How about the holes in the block? The threads there must be clean as well or you can't tighten properly. Lube the bolts and leave them to drain. If the bolt holes aren't clean they will need a touch of a tap and then blow them out to make sure they're clean.

i blew air inside every hole in the engine block and head

my torque wrench markings start at 42nm, so any lower setting wont be exact, does it rly matter that its so precise?

new and old bolt comparison

new is on left

Oops,
I mis-read the torque values, Its 20nm, allow to settle then 30nm, then 90 degrees. The torque figures are quite important. If signifiicantly low the gasket may leak, slightly low and the bolts may fail through fatigue, too high and they may fail through overload. A wrench that starts at 42nm won't do.

Robert G8RPI.

Just blowing out the hole won't clean the threads! Try screwing in a new bolt by hand, if it goes in easily fine, if not you may need to just run a tap into each one to clean the threads, If the threads are dirty in the holes you WILL NOT be able to torque them properly!

bolts are torqued down but i didnt put water in the threads, hope all is good, just have to time it tomorrow

mhm, cant even put on cam cover
it sticks out on one side
what am i doing wrong