I have a 98 4.3 V6 4×4.. It runs just fine and the temp gage always stays a
little under midpoint when I’m driving. The other day I was sitting in the
parking lot waiting for my wife to finish shopping and noticed the temp gage
was almost to the red zone. I quickly turned off the truck and waited for
her return, as soon as I started the truck it cooled back down to it’s
normal temp. After it cooled down, I check the fluid level and it was full
to the top. Today I stopped on the way home from work at a Mc Donald’s
drive through and then parked to eat my burger. Again the temp started to
rise. I let it go and it just about got into the red zone. I finished eating
and got back on the road and the temp immediately went back to the normal
range. When I got home I tried to spin the fan blade and it did have some
resistance to movement. So it must be working somewhat.
- I sort of ruled out the thermostat as it keeps the temp at the normal
level most of the time.
– The radiator isn’t leaking and must be doing it’s job. But maybe not good
enough?
– I have no idea how much restiance the fan should have when hot. Is there a
measurement I could make to test that, or should it be locked tight when
hot?
Anyone have any suggestions, other then not eating fast food.. LOL
Joel
- Hide quoted text — Show quoted text -
Joel wrote:
> I have a 98 4.3 V6 4×4.. It runs just fine and the temp gage always stays a
> little under midpoint when I’m driving. The other day I was sitting in the
> parking lot waiting for my wife to finish shopping and noticed the temp gage
> was almost to the red zone. I quickly turned off the truck and waited for
> her return, as soon as I started the truck it cooled back down to it’s
> normal temp. After it cooled down, I check the fluid level and it was full
> to the top. Today I stopped on the way home from work at a Mc Donald’s
> drive through and then parked to eat my burger. Again the temp started to
> rise. I let it go and it just about got into the red zone. I finished eating
> and got back on the road and the temp immediately went back to the normal
> range. When I got home I tried to spin the fan blade and it did have some
> resistance to movement. So it must be working somewhat.
> – I sort of ruled out the thermostat as it keeps the temp at the normal
> level most of the time.
> – The radiator isn’t leaking and must be doing it’s job. But maybe not good
> enough?
> – I have no idea how much restiance the fan should have when hot. Is there a
> measurement I could make to test that, or should it be locked tight when
> hot?
> Anyone have any suggestions, other then not eating fast food.. LOL
> Joel
Fan clutch testing:
http://www.barneymc.com/toy_root/techneek/fan_clch.htm
–
Roger
- Hide quoted text — Show quoted text -
"Joel" <J…@cyberbest.com> wrote in message <news:gHq3d.194$zy2.55@fe25.usenetserver.com>…
> I have a 98 4.3 V6 4×4.. It runs just fine and the temp gage always stays a
> little under midpoint when I’m driving. The other day I was sitting in the
> parking lot waiting for my wife to finish shopping and noticed the temp gage
> was almost to the red zone. I quickly turned off the truck and waited for
> her return, as soon as I started the truck it cooled back down to it’s
> normal temp. After it cooled down, I check the fluid level and it was full
> to the top. Today I stopped on the way home from work at a Mc Donald’s
> drive through and then parked to eat my burger. Again the temp started to
> rise. I let it go and it just about got into the red zone. I finished eating
> and got back on the road and the temp immediately went back to the normal
> range. When I got home I tried to spin the fan blade and it did have some
> resistance to movement. So it must be working somewhat.
> – I sort of ruled out the thermostat as it keeps the temp at the normal
> level most of the time.
> – The radiator isn’t leaking and must be doing it’s job. But maybe not good
> enough?
> – I have no idea how much restiance the fan should have when hot. Is there a
> measurement I could make to test that, or should it be locked tight when
> hot?
> Anyone have any suggestions, other then not eating fast food.. LOL
> Joel
i had the same problem with my 99′ 4runner. i replaced everyting,
themostat, cap, water pump, flushed the coolant twice. it only had
79k miles on it and the radiator ended up being clogged. they
pressure tested it and could never tell the radiator was bad. but it
had the same symptoms it would overheat while at idle or stopped and
it would cool down while moving or if the heater was turned on. i
would just replace the thermostat 1st, since its the easiest thing to
replace, but im thinking its the radiator, or possible air trapped in
the coolant.
check the cooling fins on the radiator, probably a bunch of them loose esp
near the bottom. When you drive, the ram air provides extra cooling, when
you idle while stopped, the rad is not getting cooled enough by the fan
alone. when the temp is up, just open the hood and the fan should be turning
full speed, if not then check it out, fuse ? Else take it to a rad shop for
test or just change it if it’s over 5 years old. Not worth letting it die
back in the bush somewhere.
regards
"Joel" <J…@cyberbest.com> wrote in message
news:gHq3d.194$zy2.55@fe25.usenetserver.com…
- Hide quoted text — Show quoted text -
> I have a 98 4.3 V6 4×4.. It runs just fine and the temp gage always stays
a
> little under midpoint when I’m driving. The other day I was sitting in the
> parking lot waiting for my wife to finish shopping and noticed the temp
gage
> was almost to the red zone. I quickly turned off the truck and waited for
> her return, as soon as I started the truck it cooled back down to it’s
> normal temp. After it cooled down, I check the fluid level and it was full
> to the top. Today I stopped on the way home from work at a Mc Donald’s
> drive through and then parked to eat my burger. Again the temp started to
> rise. I let it go and it just about got into the red zone. I finished
eating
> and got back on the road and the temp immediately went back to the normal
> range. When I got home I tried to spin the fan blade and it did have some
> resistance to movement. So it must be working somewhat.
> – I sort of ruled out the thermostat as it keeps the temp at the normal
> level most of the time.
> – The radiator isn’t leaking and must be doing it’s job. But maybe not
good
> enough?
> – I have no idea how much restiance the fan should have when hot. Is there
a
> measurement I could make to test that, or should it be locked tight when
> hot?
> Anyone have any suggestions, other then not eating fast food.. LOL
> Joel
"Guylaine J. Parisien" <parisien6…@rogers.com> wrote in message
news:sfe4d.37495$RTE1.20742@news01.bloor.is.net.cable.rogers.com…
- Hide quoted text — Show quoted text -
> check the cooling fins on the radiator, probably a bunch of them loose esp
> near the bottom. When you drive, the ram air provides extra cooling, when
> you idle while stopped, the rad is not getting cooled enough by the fan
> alone. when the temp is up, just open the hood and the fan should be
turning
> full speed, if not then check it out, fuse ? Else take it to a rad shop
for
> test or just change it if it’s over 5 years old. Not worth letting it die
> back in the bush somewhere.
> regards
> "Joel" <J…@cyberbest.com> wrote in message
> news:gHq3d.194$zy2.55@fe25.usenetserver.com…
> > I have a 98 4.3 V6 4×4.. It runs just fine and the temp gage always
stays
> a
> > little under midpoint when I’m driving. The other day I was sitting in
the
> > parking lot waiting for my wife to finish shopping and noticed the temp
> gage
> > was almost to the red zone. I quickly turned off the truck and waited
for
> > her return, as soon as I started the truck it cooled back down to it’s
> > normal temp. After it cooled down, I check the fluid level and it was
full
> > to the top. Today I stopped on the way home from work at a Mc Donald’s
> > drive through and then parked to eat my burger. Again the temp started
to
> > rise. I let it go and it just about got into the red zone. I finished
> eating
> > and got back on the road and the temp immediately went back to the
normal
> > range. When I got home I tried to spin the fan blade and it did have
some
> > resistance to movement. So it must be working somewhat.
> > – I sort of ruled out the thermostat as it keeps the temp at the normal
> > level most of the time.
> > – The radiator isn’t leaking and must be doing it’s job. But maybe not
> good
> > enough?
> > – I have no idea how much restiance the fan should have when hot. Is
there
> a
> > measurement I could make to test that, or should it be locked tight when
> > hot?
> > Anyone have any suggestions, other then not eating fast food.. LOL
> > Joel
I used this a few years ago to determine if the radiator was clogged. Start
the engine from cold. After just a few minutes, start feeling the front of
the radiator for variations in temperature. The radiator should warm up all
over pretty evenly. If you feel a lot of cold areas, and some warm areas,
the radiator is probably clogged.
I had the same symptoms and did the same things you did when my ’82 Toyota
Pickup would overheat, then suddenly cool down when driving it. My fix was
to finally have the radiator rodded out and pressure checked.
Then it worked fine.
"Joel" <J…@cyberbest.com> wrote in message
news:gHq3d.194$zy2.55@fe25.usenetserver.com…
- Hide quoted text — Show quoted text -
>I have a 98 4.3 V6 4×4.. It runs just fine and the temp gage always stays a
>little under midpoint when I’m driving. The other day I was sitting in the
>parking lot waiting for my wife to finish shopping and noticed the temp
>gage was almost to the red zone. I quickly turned off the truck and waited
>for her return, as soon as I started the truck it cooled back down to it’s
>normal temp. After it cooled down, I check the fluid level and it was full
>to the top. Today I stopped on the way home from work at a Mc Donald’s
>drive through and then parked to eat my burger. Again the temp started to
>rise. I let it go and it just about got into the red zone. I finished
>eating and got back on the road and the temp immediately went back to the
>normal range. When I got home I tried to spin the fan blade and it did
>have some resistance to movement. So it must be working somewhat.
> – I sort of ruled out the thermostat as it keeps the temp at the normal
> level most of the time.
> – The radiator isn’t leaking and must be doing it’s job. But maybe not
> good enough?
> – I have no idea how much restiance the fan should have when hot. Is there
> a measurement I could make to test that, or should it be locked tight when
> hot?
> Anyone have any suggestions, other then not eating fast food.. LOL
> Joel