Volvo Maintenance Hints for 7xx/9xx - Bill Garland's Nuclear ...

to avoid over-tightening.
[Tip from Underhood Service Magazine] One vehicle manufacturer warns against using antiseize because
antiseize acts like a lubricant and may allow the plugs to be overtightened, which can damage the threads. If
you do use antiseize on the threads, their advice is to reduce the tightening torque on the plugs 40%.
[Tip from Autolite] We do not recommend the use of any anti seize products for installing spark plugs. Antiseize
compounds are typically composed of metallic, electrically conductive ingredients. If antiseize compounds come
in contact with the core nose of the plugs, it can lead to a misfire condition. Antiseize compounds can also
have a torque multiplying effect when installing plugs. This can lead to thread distortion and thread galling
resulting in cylinder head damage. Autolite spark plugs are nickel plated to resist the effects of corrosion and
seizing. However, plug seizure is aggravated further when steel plugs are installed into aluminum cylinder
heads for a long period of time. You may want to consider the periodic inspection of the plugs to reduce the
likelihood of plug seizure during extended plug service intervals.
If You Do Not Have A Torque Wrench At Hand:
Always use a torque wrench to install spark plugs. However, if
you do not have one at hand, you can use the following
technique as a rough approximation [courtesy Denso]:
● First install sparkplug finger tight
● Then tighten another one-half turn using a wrench and
spark plug socket
1. First intall plug
finger tight
2. Then tighten 1/2 turn.
Better to use torque
wrench.
Caution on Spark Plug Number Four. [Tip from Rob Bareiss] I can't tell you how many people have screwed up
the #4 plug. It seems to be difficult for some people to grasp the concept that since the plug came out at an
angle, it needs to go back in at an angle. Too many of these have been crossthreaded.
Cylinder Head and Valves:
Top Dead Center. How do I locate "top dead center (TDC)" on my B230 engine? [John Sullivan] Some tips on
locating engine position:
● When the notch/slot in the crank washer is aligned with the vertical mark on the block, the #1 piston is at
TDC
● When the cam gear's mark is aligned with the mark on the timing belt back cover (about 11 o'clock), both
valves for the #1 cylinder are fully closed, and...
● When the intermediate shaft gear's mark is aligned with the mark on the timing belt back cover (about 3
o'clock), the distributor's rotor is pointed at the #1 cylinder ignition wire contact in the distributor cap--and
that rotor is also aligned with the mark on the distributor's base.
Intake and Exhaust Manifold Gasket Replacement.
Exhaust Manifold Gaskets. See the FAQ section for instructions on diagnosing and replacing exhaust manifold
gaskets and safely removing the manifold nuts.
Intake Manifold Gasket.