Omega Owners Forum
Omega Help Area => Omega General Help => Topic started by: gibby on 25 November 2011, 21:56:00
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WHEN I WAS CHANGING THE HEAD GASKET on omega z22xe 2198cc 2001 auto, I HAD THE INFORMATIOM OF TIGHTENING THE HEAD AS FOLLOWS:first stage 25NM, second stage 90 DEGRES and last 90 degres again. But after looking on the forum it seems to continue to fourth stage 90 degres and then last stage 15 degrees.
SO MY QUESTION IS, SHOULD I JUST LIVE AS IT IS OR ADD ANOTHER 90DEGREES THEN 15 DEGREES? OR SHOULD I BUY ANOTHER SET OF BOLTS AND START ALL OVER AGAIN? PLEASE ADVISE.
I'M VERY SORRY FOR BEING A PAIN THIS FORUM.
GIBBY
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i think the 2.2 petrol is -
25nm
90deg
90deg
90deg
optional 15deg tolerance turn
someone will be along to confirm :y
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i think the 2.2 petrol is -
25nm
90deg
90deg
90deg
optional 15deg tolerance turn
someone will be along to confirm :y
correct... If using pattern bolts, dont use the tolerance turn!
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i think the 2.2 petrol is -
25nm
90deg
90deg
90deg
optional 15deg tolerance turn
someone will be along to confirm :y
SO DO I NEED TO TORQUE ANOTHER 90 DEGREES AGAIN WITH THE SAME BOLTS OR I NEED TO BUY ANOTHER SET OF BOLTS AND REDO THE TORQUING.?
correct... If using pattern bolts, dont use the tolerance turn!
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Need another 90 degrees by the sound of it. :-\
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If it's all back together, you'll have to remove the cambelt and camshafts to further tighten the bolts.. on that basis, Id' bite the bullet, and re-do the HG, use new bolts and do up to the correct torque.
Chalk it up to experience :y
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I'd do as Albs suggested. If it then causes problems you can do as James suggested. ;) ;)
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I'd do as Albs suggested. If it then causes problems you can do as James suggested. ;) ;)
TBH Andy I'd tend to agree, didn't want to advise it though, on the basis that he'll have to do quite a degree of work to access the bolts (cambelt / camshaft removal) - and on the 4 pot, that's more than half way to just undoing them and popping a new HG in there...
:-\
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I'd do as Albs suggested. If it then causes problems you can do as James suggested. ;) ;)
TBH Andy I'd tend to agree, didn't want to advise it though, on the basis that he'll have to do quite a degree of work to access the bolts (cambelt / camshaft removal) - and on the 4 pot, that's more than half way to just undoing them and popping a new HG in there...
:-\
I see where you're coming from, but your own labour doesn't cost anything does it. If you were paying someone else though ..... ;) ;)
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surely op wont have to change headgasket as he already has a new one on?? thats how the thread started
or am i missing something here :-\ :-\
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I'd do as Albs suggested. If it then causes problems you can do as James suggested. ;) ;)
TBH Andy I'd tend to agree, didn't want to advise it though, on the basis that he'll have to do quite a degree of work to access the bolts (cambelt / camshaft removal) - and on the 4 pot, that's more than half way to just undoing them and popping a new HG in there...
:-\
I see where you're coming from, but your own labour doesn't cost anything does it. If you were paying someone else though ..... ;) ;)
Yep agreed... if you've got a spare couple of hours to whip the cams out and tighten them another 90 deg, you have nothing to lose by trying :y
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Just re read this.
We need to clarify whether or not the car has been driven.
If it's been started / ran / driven on a HG that's not been torqued through all the stages, then that MAY cause issues.
If it's not even been used, then no worries, tighten through another 90 deg, and job's a goodun :y
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Iirc its been started for a short time but is misfiring. :-\
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just as some info for myself james what problems could occur if the car has been run without the correct torque sequence ? ;)
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just as some info for myself james what problems could occur if the car has been run without the correct torque sequence ? ;)
If the head has not been torqued enough, or has an uneven clamping force on the head gasket, due to not being tightened in the right sequence, it could have all sort of effects, namely cross contamination of fluids, exhaust gasses in the coolant system, and loss of compression causing misfires..
.
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namely cross contamination of fluids, exhaust gasses in the coolant system, and loss of compression causing misfires
hmmm ok-----not a lot then ;D ;D
well that should solve op's misfire thread :y
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Surely the last 90deg is not doing a lot, just torquing up for 40,000 miles, the head should have sealed by now, its allowing for the gasket to compress with time, elasticity in the bolts and all that. I would not like to waste all the effort so far, so would ( probably ) tighten up the bolts the final 90 deg and go for it.
Ken
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Surely the last 90deg is not doing a lot, just torquing up for 40,000 miles, the head should have sealed by now, its allowing for the gasket to compress with time, elasticity in the bolts and all that. I would not like to waste all the effort so far, so would ( probably ) tighten up the bolts the final 90 deg and go for it.
Ken
If it were mine, I'd do exactly that....
But, I'd feel bad advising the guy to strip off his cambelt, take the cams out, and tighten the bolts, when, having done that, he's practically at the stage of popping it off and changing the HG anyway.. :-\
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I think we are both thinking approx the same way its just the delay and cost in sourcing a new gasket and bolts may upset his plans. Hey I get impatient some times......
Ken
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I forgot to mention, its easy to do on a Desmond :y :y :y
ken
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The bolts will be fine as they likely won't have been tightened beyond their elastic limit yet, so no need to replace them IMHO.
As to the head gasket, I'd say it would probably have failed catastrophically by now if the clamping force on it was not sufficient. If the car hasn't been driven yet due to other problems then that makes it less likely to have failed as if the engine has not been used under load cylinder pressures will have been low.
Simple way to check, though. Measure the compression. :y
If we're certain that they were tightened consistently in the right order, but just 90 degrees too little, I would wind on another 90 degrees, in the correct tightening order, and hope for the best, TBH. Otherwise, I'd slacken all bolts in the correct order, then perform the whole sequence again, in the correct order.
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Just re read this.
We need to clarify whether or not the car has been driven.
If it's been started / ran / driven on a HG that's not been torqued through all the stages, then that MAY cause issues.
If it's not even been used, then no worries, tighten through another 90 deg, and job's a goodun :y
Hello boss, then thus fine because I just started it and run the engine just less than ten minutes and switched off without driving an inch. thax for that advice.