head gaskets fail for a number of reasons,
improper installation procedures,
corrosion, due to old coolant
over heating, due to low coolant,
a bad water pump or restricted t-stat or radiator
detonation, due to bad gas or improper ignition timing,
improper tuning of the fuel/air ratio etc.
in most cases if caught early, simply cleaning of the head and block and replacing the head gasket with the proper procedure after locating and correcting the cause of the head gasket failure will be all that's required,
if how ever you constantly try to run an engine with a defective head gasket you'll damage the block or heads in a short time, thru several reasons.
some common indicators of a blown head gasket, are white smoke from the exhaust (usually with a sweet smell)
loss of coolant with no obvious leaks, over heating of the engine, the engine runs rough and a inspection of the spark plugs and a compression test will usually show the defective cylinders, due to the condition of the spark plugs or the lower cylinder pressure readings, when you do a compression test on all cylinders
ideally a head gaskets bore will match or be slightly larger than the cylinder, a smaller bore gasket tends to over lap the combustion chamber edge and cause a hot spot that tends to aggravate detonation problems.
your SHOP MANUAL will give you both the correct gasket and the procedure and torque readings and tightening sequence of the head bolts.
obviously the condition of the block and head surfaces to be sealed and the clamping sequence and torque values use on the head bolts and any sealant used will vary but must match the application,(SHOP MANUALS, and HEAD GASKET MANUFACTURERS INSTRUCTIONS ARE A BIG HELP)
http://www.goodvibesracing.com/SBC_Head_Gaskets.htm
when installing almost any head gasket, but especially with a copper head gasket be sure to put on two wet even coats on both sides of the head gasket and install and torque while the copper coat sprays still damp ,the spray fills in micro flaws in the machined surface
Keep in mind there are solid copper head gaskets , Ive used for decades that you simply spray with copper coat and install damp and torque in place, and the TITAN style with a steel fire ring, sandwiched between to layers of copper, Ive never used the titan style but have used the solid copper gaskets extensively with good results, in both cases the head gasket must be slightly recessed between the head and block ,not sticking out into the edge of the combustion chamber
READ THE INFO IN THE LINKS THERES A GREAT DEAL TO BE LEARNED
http://garage.grumpysperformance.com/index.php?threads/sbc-head-gasket-choice.11070/#post-79067
http://garage.grumpysperformance.com/index.php?threads/head-gasket.10085/#post-39429
http://garage.grumpysperformance.co...ad-gasket-for-aluminum-heads.4403/#post-26317
http://garage.grumpysperformance.co...asket-bore-size-vs-bore-size.2681/#post-11603
viewtopic.php?f=50&t=1222
viewtopic.php?f=50&t=827&p=4572&hilit=copper#p4572
http://www.enginebuildermag.com/Article ... skets.aspx
http://www.aa1car.com/library/2005/ic010532.htm
http://www.import-car.com/Article/61817 ... _fail.aspx
http://www.aa1car.com/library/gasket_failure.htm
http://www.aa1car.com/library/ic697.htm
http://www.cswnet.com/~carother/compression_ratio.htm
http://www.misterfixit.com/deton.htm
http://racingarticles.com/article_racing-10.html
http://www.asashop.org/autoinc/jan97/gasket.htm
http://www.ehow.com/how_2316551_repair- ... asket.html
if you don,t have a particular engines torque sequence its a safe bet that you start with the center head bolts and tighten each , in stages in a spiral outward pattern, then repeat the sequence with each increased torque setting movng in that same spiral increasing diam spiral moving from the center to outer bolt locations.
the slight miss alignment on the coolant ports has no effect
SBC HEADS
Big Chevy
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