gasket, before thoroughly cleaning the engine itself. While oil that makes it to the undercarriage of a vehicle may be from the valve cover, a faulty oil pan gasket may also be to blame.
Engine MisfireWhat Can Cause a Valve Cover Gasket to Fail?
While all valve cover gaskets are prone to leakage with time, several different factors can also play a key role in the depletion of such a gasket’s structural integrity. The vast majority of which are at least partially maintenance-related in nature.
#1 – Infrequent Oil Changes
Perhaps the most significant cause of premature valve cover gasket failure is infrequent engine service. Fresh engine oil, which is changed at a regular interval, contains a number of additives that are intended to prevent gasket deterioration.
With time these additives begin to break down, which in turn, leaves an engine’s valve cover gasket(s) vulnerable to accelerated wear and aging. This often occurs when items of routine maintenance are ignored for extended periods of time.
#2 – Overheating
Another leading cause of valve cover gasket failure is overheating. All engines are intended to operate at a predetermined temperature. If this predetermined value is exceeded, as in the case of overheating, an engine’s gaskets become heat stressed, which poses an accelerated risk of cracking and blowout.
Overheating is not only hard on an engine’s valve cover gasket(s), but also jeopardizes the integrity of other vital seals, such as the head gasket. It is not uncommon to find multiple failed gaskets on a single engine, in the case of severe engine overheating.
#3 – Over/Under Tightened Valve Cover Bolts
Additionally, previously replaced valve cover gaskets often begin leaking in short order, if an engine’s valve cover bolts are not properly torqued upon installation.
Over-tightening of these bolts can lead to improper gasket seating or pinched/flattened gasket surfaces. On the other hand, the under-tightening of these bolts often prevents a suitable seal from ever forming between each metallic surface.
Is a Valve Cover Gasket leak serious?
In the vast majority of cases, a valve cover gasket leak is not considered to be extremely serious. This is especially true of minor leaks, which do not heavily contaminate an engine’s external surfaces.
Generally, a valve cover gasket leak is only considered to be serious if it becomes severe enough to cause significant oil loss.
Additionally, a valve cover gasket leak that causes a misfire condition is also cause for concern. This occurs when run-off from a leak leads to the presence of oil in a spark plug well, thereby contaminating a spark plugs electrode and insulator.
In any case, it is considered good practice to replace a leaking valve cover gasket within a reasonable amount of time. A leak of this nature will only progress in severity, eventually reaching a level of severity consistent with that described above.
Being proactive with such repairs helps to minimize the chance of any drivability-related symptoms.