Top 4 Mistakes Car Owners Make (DIY Fails)

one, two, three, four! Rev up your engines! It’s time for the Scotty Kilmer Channel,
in the 42 years and I’ve been working on cars I’ve had to fix a lot of
mistakes that other people have made, so today I’m going to show you how to avoid
common auto repair mistakes, now it’s great if you change your own oil and
filter, but here’s a mistake I’ve seen destroy engines, when you remove the old
oil filter make sure that this rubber gasket is still on the old filter,
because sometimes the old gasket comes off when you take the filter off, and
sticks onto the engine, and you won’t see it sticking on the engine because the
oil filters usually in a hidden location, like this Toyota, it’s hidden down here,
you can screw it in but you can’t see what you’re doing, so if there’s a gas
gets stuck on there you might miss it, so be sure to check your old one to make
sure that the old gasket is still on when you take it off, because if the old
gasket is stuck on the engine and you put another one on top of it, you’ll
double gasket it and the oil will leak, I’ve seen engines blow up because of
this, and of course remember before you put the new filter on, put a little oil
on your finger and put oil all around the gasket, so it seals and doesn’t leak,
then when you put the new filter on, not only will it not leak, but it’ll be
easier to take off the next time, now another common mistake I’ve seen cost
people a lot of money is, leaving the battery connected when electrical work
is done, so whenever you’re doing electrical work on a car, disconnect one of the
cables and take it off the battery, that way you won’t short any electrical parts
out, like this, let’s say you’re working on the alternator, well if it’s got live
power and this wire touches anything, it can short the alternator and the wiring
of the car out, but if you’re taking off one of the battery cables, there’s no
more power flowing through the system, and you can’t hurt anything, now you
might think, oh I’m careful this isn’t going to happen to me, but hey, one little
mistake you can ruin a fifteen hundred dollar computer, it’s a lot easier just
taking one of the battery cables off, and putting it back on when you’re done
working, now the next common mistake I see concerns changing out spark plugs,
never change out spark plugs on engine that’s hot, wait until the engine
has cooled down, modern cars have aluminum heads which is very soft, over
the years I’ve had to rethread many of these heads and sometimes had to replace
them, so if you’re planning on changing your spark plugs, do it first thing
in the morning or wait a couple hours until the engine is cooled down, so you
don’t do any damage, and if you want to do the job right, put some anti-seize
lubrication on the threads of the spark plug before you put it back in the
engine, now the last common mistake I’m going to talk about is motor oil, some
people think that a heavier weight oil is better for their engine, like a 20
weight 50 instead of a 10 weight 40, well guess what, that’s not true, always look
at your car and see what they suggest to use, in this Toyota it says use 10 weight
thirty oil, so that’s what you should use because the lighter oil will flow better
which is really important for overhead cam engines, in overhead cam engines the
cam is in the top of the engine, and if you use a heavier oil, it can take longer
for that heavy oil to get to the cam, so the cam will wear out faster, so in this
case using a heavier 20 weight 50 oil can actually make the engine wear out
faster, and the last thing anybody wants is an engine that wears out faster, you
want them to last as long as possible, so just stick with the oil that suggested
on the engine, in this case it’s 10w30, so now you know how to save yourself a lot
of grief and avoid these common auto repair mistakes, and remember if you have
any car questions just visit and I’ll answer them