Radiator building pressure when cold... CIVIC 06 VTi

[aoun556]

@ bilal..i changed head gasket of my civic 2000 a week before coz of bubbles formation and water reduction in radiator.after changing gasket water reduction reduces almost 80 percent but bubbles were still forming on hot engine so today my mechanic tightened head bolts and i think my problem is solved ...so before gasket replacement try it once.

[billa69]

thanks aoun brother will surely go for the head bolt tightening tomorrow ,btw did your mechanic use a torque wrench to tighten your head bolts if yes please ask him the particular torque figure he used and which gasket did he use the metal one or the fiber one
plz let me know asap
thanks

[Angeldust]

can you specify on what magnitude/torque should I tighten the head bolts again and is there some sort of sequence/pattern we have to follow while tightening them

For such a specialized suggestion give a question to Xulfiqar.

[aoun556]

thanks aoun brother will surely go for the head bolt tightening tomorrow ,btw did your mechanic use a torque wrench to tighten your head bolts if yes please ask him the particular torque figure he used and which gasket did he use the metal one or the fiber one
plz let me know asap
thanks

i dont knw abt torque wrench...and he didnt use metal gasket as he told me metal one comes with original engine but when gasket is changed fiber one is used.I also asked from honda 3s and they replied the same.

[Xulfiqar]

the tightening values are this - convert to Nm if required

stage 1 = 15 lb/ft
stage 2 = 36 lb/ft
stage 3 = 49 lb/ft
stage 4 = retighten bolt 1 and 2 to 49 lb/ft again after 10 minutes

bolt sequence

7 6 1 3 X
9 4 2 5 8

the bolt threads should be buffed clean and the bolt holes should be run with a tap (aka tub in local mechanic language) - to clean those threads too - the bolt threads should be oiled very lightly - 1 drop of singer machine oil on them before inserting them into the holes, when they are 99% in their holes - put a drop of engine oil on the washers, now tighten in the stages mentioned above.

btw there is no Honda part no. for any sort of fiber heaggasket for this engine, There is only a metal headgasket. Its only one time useable as it has ridges on it that actually seal the head to the block.

[fahadwizz]

This cold pressure you are talking about , isnt it more of a negative pressure? I do have this in my system and i thought it was normal.

[Xulfiqar]

People tend to just hear the sound of air rushing and think its pressure, if coolant or the cap ejects from the cap then its pressure - this can also be verified first by squeezing a pipe - if its rock hard, then the system has pressure.

But this is done only after 1 minute of cold start.

If the system held vacuum (negative pressure) then the system is perfectly OK.