Friday, July 10th, 2020

A VIEW FROM THE PUMPS – FIXING THE LEAK

Today’s cars are running hotter, faster, and with so many dissimilar components it is nothing short of a miracle that fluid leaks do not manifest themselves within the first few thousand miles.  In the beginning the art of gasketing was relatively simple, two hunks of cast iron or steel machined to a somewhat smooth surface with a piece of cork between them.  After a while, the cork would deteriorate, and it was a simple fix to separate the two pieces of metal and change the gasket.  Also, back in the day the most driveways were made of stone or then macadam and in the higher priced neighborhoods concrete.  Grease or oil stains were the rule than the opposite.  And then when it finally got too bad a gallon of Muriatic acid, a stiff broom and lots of water would clean up the mess but destroy the environment.  Personally, my favorite was TIDE soap and gasoline.

Todays driveways are not coated or made of pavers the homeowners pay thousands of dollars to have and maintain.  You would never park a leaker on a sealed or paved driveway that your friend or neighbor just spent thousands of dollars to install and still expect that friendship to survive.

Now welcome to the 21st century, we no longer have two slabs of metal to contend with, we have aluminum attached to steel or plastic mounted on steel or aluminum.  Intake manifold plenums are mounted onto aluminum or cast intakes and are expected to keep the oil, coolant and vacuum all neatly segregated from each other and above all not hitting the ground.  A classic example of poor gasketing with catastrophic results was the Ford 4.2 V6 engine.  The intake was made of plastic and the heads were steel and as the gasketing failed due to dissimilar metallurgical issues, different expansion rates the coolant gaskets would start to seep not on the ground or on the exterior of the engine but into the cylinder head and combustion chamber.  On a hot engine that was running this coolant would burn off in the combustion sequence, but when it was cooling down eventually the number one combustion chamber would fill up with coolant.  The result of this phenomena was one or two conditions.  If you were lucky the engine burnt enough coolant to make the engine overheat and you only ruined a head gasket.  If your luck was really bad then the combustion chamber would fill up with fluid, and as we all know water does not compress, and the force of the piston hitting the coolant and forcing it into the bottom of the head would then bend the piston’s connecting rod making the engine a virtual anchor.

General motors had a similar issue when they first went to plastic intakes except these fluid leaks would go directly into the crank case.  Once again there would never be an external leak but there would be enough coolant in the crank case to make the vehicle overheat.  First symptoms were when checking the oil level, it would be two to three quarts overfull and the oil would look like a chocolate shake.  Once again head gaskets were assumed to be the issue but, in many cases, this was not the correct diagnosis.  Many an engine was disassembled only to find that the head gaskets were not the issue.  Engines were reassembled and shortly after the repair they developed a knocking condition in the bottom end of the engine, because the coolant would eat up the bearing surfaces and the bearings would come apart.

The moral to this first part of this series is vehicle owners must take responsibility in knowing how to and when to check their fluid levels or developing a relationship with a professional that knows what to look for.  This must be done in a timely and regular schedule because these new and wonderful engines that are out there now are not very forgiving and it is rare that you as an owner gets a second chance.

As always, I close with my favorite warnings:

LACK OF COMMON SENSE WILL ALWAYS COST YOU DOLLARS AND CENTS, AND PREVENTIVE MAINTENANCE STARTS AT MILE 000001.

GREGG MARRAPODI

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