There are lots of plastic parts under the hood of an automobile these days, and they’ll actually last longer than metal in most cases if you take proper care of them. Don’t spray anything under the hood; don’t use any chemicals that might dissolve the plastic, and above and beyond all, take proper care of the cooling system.  The reason for that is a lot of the plastic lives in the cooling system.

Now there are these tales going around that if your car has long life coolant, you’ve got to take it out, got to put the old fashioned green stuff in there to prevent problems such as when the coolant turns muddy and damages the cooling system.  Well, that’s not really true.  What you need to do is take proper care of that long-life coolant, and that means that you do more than use the old-fashioned hydrometer to look at the color of it and to see what its freeze protection is.  So you can look like brand new but yet be very acidic.

That means you need to use pH test strips and you need to do that at least twice a year.  You’re going to check the pH.  When the pH drops below manufacturers’ specifications, you need to change the coolant.  The system needs to be flushed and new coolant of the proper type put in it.

What are you trying to avoid? Well you’re trying to avoid problems like we had with this plastic tank radiator which developed a crack, and that crack leaked, and as it leaked it collected down at the bottom and as you can see there is literally nothing left of this radiator.  So that’s a big problem!

Another problem, if you don’t take care of the cooling system, many water pumps these days have plastic impellers, like this one, and it cracked!  It literally fell apart inside the car.  That caused the engine to overheat, and the overheated engine blew the head gasket.  It’s kind of a long sad story, but the bottom line is the cooling system on that car was not properly maintained. 

Intake manifolds are another place where you’ll find plastic on a lot of automobiles, and we have one here where part of the port in it has collapsed.  This allowed coolant to go right straight into the throttle body and down into the engine, and what happened there was it filled the oil with coolant and that damaged the engine.  All because of poor cooling system maintenance.  So check the P-H.  Do it at least twice a year, and never leave the coolant in the car longer than the vehicle manufacturer recommends in the owner’s manual. 


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