What is that leaking from your car?

Stopping leaks is a frequent request at all auto repair shops. There are all kinds of fluids required for the basic function of your automobile.  None of these fluids are friendly to the environment.  And you would prefer that all of them stayed in the system they were meant to be in.

Finding leaks goes from the ridiculously obvious to the totally obscure. (Ask me about the leaking frame I once repaired.)  There seems there is no consensus on the severity of leaks.  One man’s gusher is another’s slight drip. The measure of the severity of a leak is directly related to either the amount of money required to keep the system full or the amount of mess the owner can deal with on the driveway or in the garage or carport.

It seems that the 21st century has produced perfect seals and gaskets.  I think the Japanese were the first to produce vehicles with no leaks.  I am sure the British will be the last to produce vehicles that do not leak some type of liquid.  Where many people tolerated oil leaks in the past I think most now expect no stains on the concrete. If your mid life crisis has you snapping up that British sports car you always wanted, remember that when it stops leaking, it means you are out of the given fluid that was leaking and headed for catastrophic failure.

Yes, old British cars leak.  If you can get them down to just weeping or oozing, you are a genius.

Finding leaks is all physical science (chemistry and physics that is).  A good first step is determining what fluid is leaking.  Sometimes this is easier said than done.

An oil leak can have several sources.  Sometimes finding the source takes some detective work.  There is oil in the engine, transmission, transfer case, differential, and power steering system. Some of these components may share their oil with each other.  Some may be attached to the other but share no fluid.

As you can imagine many leaks are obvious.  Just look for the wet spot under the vehicle and find the highest point that is wet.

That is probably your source.  Gravity comes into play for most leaks.

Then there are tricky leaks.  Two oil filled components are connected together.  They both contain the same type of fluid.  A leak develops in the seal between the two devices (an automatic transmission and a transfer case for example).  The transmission starts leaking into the transfer case.  There is no sign of leakage.  Unless someone is checking the levels in these components the leak could go undiscovered and even result in a failure.

When the oil level in the transfer case gets too high it gets frothed (air bubbles in the oil) and now does not lubricate properly.  The automatic transmission will get low on oil and start to slip; yet nobody has seen anything leaking out.

Engine leaks are some of the trickiest.  The engine has the most potential for leaks and some of the hardest places to look into for the source of those leaks.

Again engine leaks can be internal. There are two main liquids that circulate in an engine. They are the coolant and oil.  They can both leak internally.  These leaks manifest themselves in oil burning or coolant being boiled and sent out the exhaust system.  The solution to these internal leaks is usually expensive.

External engine oil leaks can also be sneaky.  There are many nooks, crannies and crevices for oil to hide in on their way to your garage floor.  Many times getting to the source requires some disassembly and that can mean labour dollars.

The vehicle owner can do some detective work on their own to help the mechanic locate a leak.

Sometimes certain driving conditions are required for a leak to rear its ugly head.  Coolant leaks are notorious for that.

Sometimes a water pump only leaks at a certain temperature.  Too high and the leak is steam like and invisible.  Too cold and there is no leak.  Slightly warmed up and shut off.  Voilà, the water pump leaks like a sieve.

Remember leaks are not always onto your driveway.  Make sure all the fluid levels are checked regularly.  Just because something isn’t leaking on the outside does not mean everything is okay.