bad lampe modern
one, two, three, four! rev up your engines! it's time for the scotty kilmer channel today i'm going to talk about whycertain car parts should never be made out of plastic, but many manufacturersare doing just that, now i understand that plastic is mucheasier and cheaper to make, this is a plastic thermostat that i had to changeout on this ford because it broke already, now even though this ford is onlysix years old, the thermostat inside here cracked and broke cause it's made out ofplastic, while the thermostat of this 24
year old toyota celica is still strong,it's never been changed, the housing is made out of metal, they can last foreverso why did they make this thermostat housing out of plastic, it's justcheaper, plastic is made by injection molding, the plastic can be moulded and thenthey can make a whole bunch of these things at once, when they break the mould apart, you just have to take little tangs off, it's ready for use, while in ametal thermostat, they have to make good moulds, it has to be poured, and then alot of times when it comes out it's got to be polished so it fits right, costs alot more money, even though they last a lot longer, now plastic bumpers they'reokay, they're just out in the air, they
can bend and flex you can hit people,they can bounce back up, that's okay but you don't want plastic where's thecorrosive atmosphere, as i'm quoting from a scientist here, research shows that theexposure of plastics to liquid chemicals tends to accelerate their breaking, butwhen you have a thermostat that's hidden inside the engine here, it's all hot, it'sgot all kinds of chemicals in it from the antifreeze, of course it's going tobreak down relatively fast, and in the case of this ford, to add insult toinjury, there's a little rubber hose that comes off the thermostat housing, butwhat does it go to, yet another plastic hose, and this plastic hose carriescoolant, the plastic just degraded and it
had to be replaced,now this hose used to be made out of metal, of course it's cheaper to make outof plastic, but then the heat and the chemicals in the antifreeze eventuallybreak down, and it'll start leaking and you got to replace something that couldhave lasted almost forever, now plastic has some good uses, in the old saturn'sthey had plastic doors and plastic fender panel,they don't rust, so that's an okay use for plastic, but what about door handles,i spend hours every year replacing people's door handles that are made outof cheap plastic, and they break when you pull on them, when i was a kid, door handles were made out of chrome plated
metal, they basically lasted forever, nowthis is a lexus, and though it looks like it, it's chrome-plated plastic and thesethings break too, and they're a pain to replace, in this case, be gentle and kindwith the door handles, don't rip them up, my wife has never broken any of theseplastic door handles, because she's cautious, but me, a lot of times i'm in ahurry and grab it and it breaks right off and then you got to replace thestupid thing, when you're talking about putting plastic under the hood of yourcar on the engine, where it gets really hot, heat soaked over time, and there'scaustic chemicals, that's just plain stupid, for another example on this ford,this is the power steering reservoir,
inside here there's a little plasticpiece that goes to the top of the pump, and they often break because it'splastic, what does plastic not like, chemicals, like power steering fluid, temperature, itgets very hot with the power steering pump, and pressure these things can putup 1,600 pounds per square inch pressure, it's stupid to use any plastic parts ona power steering system, that reminds me of a friend of mine who does heating andair conditioning working on houses, he said, scotty you said cars are bad, we haveheaters for houses that have plastic parts inside the furnace, and guess what,after a few years the plastic melts we got to take it all apart and replace it,sometimes it's just comical, look at
this, here's plastic valves inside herefor the anti-pollution system, and what did they do, they put a little heatshield to attempt to keep the heat from bothering the plastic, like it's stillunder the hood of the car, it's still going to get all kinds of heat in there and theplastic is going to degrade over time, i swear sometimes it seems that they'remaking these things just so they'll last a little bit longer than the warrantyperiod, and then they don't care anymore, now if there's no pressure stress like inan air filter box, there's just air going through it, it's perfectly fine to useplastic, but plastic and pressure and temperature again, not a good idea to useplastic, this radiator i had to replace it
because the top tank started to crack,got brittle, and was leaking coolant, i know people are going to say, scottyoh the plastic radiators they use them because they weigh less, well theyactually don't, because the plastic has to be so thick that it won't crack rightaway it actually weighs a little bit morethan a thin metal, that can take a lot more pressure and never wear out, youdon't even get me started talking about plastic headlights, when i was a kid they wereglass, the glass stayed shiny forever, just needed cleaning, this plastic stuff itgets all hazy, looks like crap, you can polish it, but then it will get hazy again in a few months, but at least with exterior plastic you can use this
plastic polish to polish it and protectit, to make it last longer, but all the mechanical parts under the hood, itdoesn't do any good for that, because they degrade from the inside out fromheat and chemicals, believe it or not, a man by the name of mattie holtzberg, madea mainly plastic copy of a ford pinto engine, let's just say it's probably agood thing it was never put into actual mass production, some people have takenthis plastic in manufacturing a little bit too far, and remember if you got anycar questions just visit the scotty kilmer channel,so if you never want to miss another one of my new car repair videos, remember toring that bell!