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cliopete
03-03-2011, 13:45
Not the order but the sequence for each bolt. Is it necessary to run the engine up to temp. slacken and re-tighten as it seems to indicate on the set of new head bolts just purchased.

Pete
Laine_16v
03-03-2011, 14:28
No not neccesary, i know plenty of engines that have never done this "warm up" procedure and are fine, some of them being highly strung engines too.

I dont know the values for F7 Engines but it will be something like 30nm in a clockwise fashion, slacken, then angle tighten clockwise rotation again.
cliopete
03-03-2011, 15:04
The instruction with the bolts gives two different sequences for the F7P & F7R engines. 5 stages for F7P & 9 stages for F7R.The extra stages being run up to temp - loosen - tighten to 25Nm - tighten thro' 107 degrees.
Just wondering if these last stages are essential. Engine gurus please advise.

Pete
dhay14
03-03-2011, 20:03
can someone state all them stages pls?
schakal
03-03-2011, 20:48
The instruction with the bolts gives two different sequences for the F7P & F7R engines. 5 stages for F7P & 9 stages for F7R.The extra stages being run up to temp - loosen - tighten to 25Nm - tighten thro' 107 degrees.
Just wondering if these last stages are essential. Engine gurus please advise.

Pete

APD put my F7R together without running it etc . have not had any problems
apart from the slight oil leak which is unrelated .
MAXIBOY
03-03-2011, 21:58
stage one..30nm
stage two..angle tighten by 50 degrees
stage three..wait for 3 minutes
stage four...loosen all bolts completely
stage five..25nm
stage six...angle tighten by 108 degrees +-3 degrees


always done the above never had an issue.. but i will always tap and clean the bolt holes and clean the bottoms out of all dirt and liquids.
cliokiz
08-03-2011, 14:30
I use the same method as Maxi has stated, works fine
Wobba
08-03-2011, 14:39
That's what I've always done too. But as MAXI says, clean the bolts holes out totally to remove chance of cracking block due to thermal expansion of any fluids trapped inside hole!
kj16v
08-03-2011, 16:36
I think the "warm up, cool down, re-tighten" sequence is for non-stretch bolts. Clios use stretch bolts