'89 Corolla running hot on highway (and other problems)

Hi folks,
I drive a 1989 Toyolla Corolla coupe, carbureted 4A-F with California
emissions, with 138k miles. I bought it used in 1999 with 94k miles.
It has a 4-speed automatic, original water pump, original radiator, new
thermostat, flushed coolant (last year). The belts are 5 years/40k
miles old and look ok though squeak and sound rough slightly for the
first couple minutes when it's very cold (I live in Boston). The
newsgroups have helped me out many times with the car, and I need your
advice now yet again:

Last year my car was running hot where the temp would creep up to
80-90% of max temp all the time. The fan wasn't kicking in. My
mechanic replaced the Fan Switch (and thermostat at the same time), and
the problem was solved, and aftewards the car would always run at 2/5
of its max temp, as it always did when newer.

For the past month, I've noticed that the temp is constantly running at
3/4 max when I'm driving past 60 mph, or past 45 mph and have a
passenger in the car. When I slow down, the temp will soon drop down.
If I run the heat, then the temp will also stay at 2/5 max, which I
think is where the car ideally wants to run. The temp does not run
high if I'm idling or driving at low speeds. The engine runs fine.
Bottom line is that when asked to do extra work to carry a passenger or
run above 60mph, the engine runs hot.

The coolant/level color looks fine. The radiator and radiator fan,
from the outside, look like they're in good shape too and appear clean
and unobstructed.
What do you recommend I do next? I'm not sure sure how my mechanic
would know where to proceed. Options a
1. get radiator flushed, see if this helps; radiator was flushed just
last year.
1b. also replace hoses and see if this helps (hoses are original as far
as I know)
2. replace radiator
3. replace water pump
4. replace radiator and water pump

#4 should definitely do the trick, but would be pricey.

--------
Other issues that have come up:
1. rear struts rarely make groaning noises (usually happens as they
decompress as I'm getting out of the car)-- when I do the "bounce" test
they seem normal firm; the car's ride is fine; how urgent is it to
replace the struts?
2. the clock went out yesterday-- could this signal an electrical
problem elsewhere? If the clock's an LED clock, which I assume, then I
would not expect it to go out..
3. gas pedal yesterday started to make quiet groaning noises when I
step on it, like a door hinge that needs WD-40... where can I lubricate
it, and with which lubricant?
4. A/C is weak right now, so hard for me to defrost the windows... has
anyone used "Freeze 12" or other R12 equivalents before? I asked my
mechanic about fixing the A/C but he said that it's impossible to get a
hold of R12 anymore (he did not mention the substitutes) and that the
only way to fix the A/C is to retrofit the system.

Thanks for your help!
John

wrote:

> For the past month, I've noticed that the temp is constantly running
at
> 3/4 max when I'm driving past 60 mph, or past 45 mph and have a
> passenger in the car. When I slow down, the temp will soon drop
down.
> If I run the heat, then the temp will also stay at 2/5 max, which I
> think is where the car ideally wants to run. The temp does not run
> high if I'm idling or driving at low speeds. The engine runs fine.
> Bottom line is that when asked to do extra work to carry a passenger
or
> run above 60mph, the engine runs hot.
> Thanks for your help!
> John

Sounds like your radiator isn't transfering away heat or there is a
large obstruction (leaves and crap) stuck between the radiator and the
condenser. Check for and clean out any obstructions by removing the
two upper radiator holddowns and tilting the top of the radiator
towards the engine. This is the most likely area to find crap and this
procedure will give you enough room to do so. Spray a water hose
through the fins of the radiator and condenser to try to clean them
also.

If this doesn't fix the problem, then replace the radiator. Its about
due anyway. Don't replace the waterpump unless it is leaking or noisy.
I'm pretty certain from your description that it is moving coolant
which is all it is supposed to do.

Keep in mind that some basic engine performance issues (advanced
timing, plugged catalytic converter, running lean) can cause higher
than normal temperatures too.

Toyota MDT in MO

About your AC problem, the following was posted on Interdynamics Web
site at one time and I'm sure some people would disagree, but they do
make freon and their procedure has worked fine for me with no problems.

The following conversion from R12 to R134a assumes there is nothing
wrong with the A/C system. Leaks must be fixed prior to this. If the
system has been vacated for a long time it is suggested that you replace
the receiver/dryer.

Vacate the system (to be legal use a capture system) and then using a
vacuum pump get it down to near -30 pounds for at least 5 minutes. This
is with the engine OFF. You must use a gage on the low pressure side to
monitor the pressure. After 5 minutes cut the vacuum pump off and let
it stand for another 5 minutes. Any increase in pressure back toward
zero would indicate a leak. If it remains near -30 then proceed.
Inject one can of R134a oil charge (has esther oil) and start the engine
with A/C on high just prior to emptying the can. The system might/might
not start cycling. Turn the A/C on high and monitor the output temp.
Now inject a regular can of R134a and start to watch the output temp.
You might need two cans of R134a but once the temp gets in normal range
stop adding freon. It is about normal for the low side pressure to be
around 30 pounds or just slightly higher but always go by the temp and
not the pressure. Of course if the temp didn't rise and you injected
the one can or pressure around 30 something is wrong. Lastly label the
system so everyone will know it's been converted. You will not want to
add any R12 once this conversion has been done, only R134a.

I purchased the R134a adapter that goes on the R134a freon can and an
adapter found at the hardware store that converts the output of the
R134a adatper to the standard R12 freon hose for about fifty cents.
This way I didn't have to change the fittings on the vehicle and I can
use my old R12 hoses and gage. This system has worked with no problems
on at least a dozen vehicles I've converted over the three year period
and my friends using this system have had no problems. I know some will
object but once again, this info came from Interdynamics web site. Hope
it helps others as much as it's helped me.

wrote:
> Hi folks,
> I drive a 1989 Toyolla Corolla coupe, carbureted 4A-F with California
> emissions, with 138k miles. I bought it used in 1999 with 94k miles.
> It has a 4-speed automatic, original water pump, original radiator, new
> thermostat, flushed coolant (last year). The belts are 5 years/40k
> miles old and look ok though squeak and sound rough slightly for the
> first couple minutes when it's very cold (I live in Boston). The
> newsgroups have helped me out many times with the car, and I need your
> advice now yet again:
>
> Last year my car was running hot where the temp would creep up to
> 80-90% of max temp all the time. The fan wasn't kicking in. My
> mechanic replaced the Fan Switch (and thermostat at the same time), and
> the problem was solved, and aftewards the car would always run at 2/5
> of its max temp, as it always did when newer.
>
> For the past month, I've noticed that the temp is constantly running at
> 3/4 max when I'm driving past 60 mph, or past 45 mph and have a
> passenger in the car. When I slow down, the temp will soon drop down.
> If I run the heat, then the temp will also stay at 2/5 max, which I
> think is where the car ideally wants to run. The temp does not run
> high if I'm idling or driving at low speeds. The engine runs fine.
> Bottom line is that when asked to do extra work to carry a passenger or
> run above 60mph, the engine runs hot.
>
> The coolant/level color looks fine. The radiator and radiator fan,
> from the outside, look like they're in good shape too and appear clean
> and unobstructed.
> What do you recommend I do next? I'm not sure sure how my mechanic
> would know where to proceed. Options a
> 1. get radiator flushed, see if this helps; radiator was flushed just
> last year.
> 1b. also replace hoses and see if this helps (hoses are original as far
> as I know)
> 2. replace radiator
> 3. replace water pump
> 4. replace radiator and water pump
>
> #4 should definitely do the trick, but would be pricey.
>
> --------
> Other issues that have come up:
> 1. rear struts rarely make groaning noises (usually happens as they
> decompress as I'm getting out of the car)-- when I do the "bounce" test
> they seem normal firm; the car's ride is fine; how urgent is it to
> replace the struts?
> 2. the clock went out yesterday-- could this signal an electrical
> problem elsewhere? If the clock's an LED clock, which I assume, then I
> would not expect it to go out..
> 3. gas pedal yesterday started to make quiet groaning noises when I
> step on it, like a door hinge that needs WD-40... where can I lubricate
> it, and with which lubricant?
> 4. A/C is weak right now, so hard for me to defrost the windows... has
> anyone used "Freeze 12" or other R12 equivalents before? I asked my
> mechanic about fixing the A/C but he said that it's impossible to get a
> hold of R12 anymore (he did not mention the substitutes) and that the
> only way to fix the A/C is to retrofit the system.
>
> Thanks for your help!
> John
>

There are a couple of important points you glossed over. (1) when charging
the system from an evacuated state AND with the compressor OFF, the new
refrigerant needs to go into the HIGH side in liquid form (invert can). This
is to prevent any liquid refrigerant from being pulled into the compressor
which will damage the inlet check valve(s). After you have added enough
refrigerant to achieve at least 10 psi, THEN you can start the compressor
and add all additional refrigerant s-l-o-w-l-y into the LOW side in liquid
form (invert can). Do not overcharge. More refrigerant beyond optimum will
reduce thermal efficiency. Adding only gas (upright can) to the low side
will usually result in excessive high side pressures and reduced cooling.

(2) Using R-134a in an R-12 system WILL reduce the thermal efficiency.
True, most people living in moderate climates won't notice too much
difference. But for those of us in the deserts of CA, NV, AZ, NM, TX where
temperatures will often exceed 105f, the thermal efficiency WILL be
noticeable above this threshold.
--

~Philip.

Joey wrote:
> About your AC problem, the following was posted on Interdynamics Web
> site at one time and I'm sure some people would disagree, but they do
> make freon and their procedure has worked fine for me with no
> problems.
> The following conversion from R12 to R134a assumes there is nothing
> wrong with the A/C system. Leaks must be fixed prior to this. If the
> system has been vacated for a long time it is suggested that you
> replace the receiver/dryer.
>
> Vacate the system (to be legal use a capture system) and then using a
> vacuum pump get it down to near -30 pounds for at least 5 minutes. This is
> with the engine OFF. You must use a gage on the low pressure
> side to monitor the pressure. After 5 minutes cut the vacuum pump
> off and let it stand for another 5 minutes. Any increase in pressure
> back toward zero would indicate a leak. If it remains near -30 then
> proceed. Inject one can of R134a oil charge (has esther oil) and
> start the engine with A/C on high just prior to emptying the can. The
> system might/might not start cycling. Turn the A/C on high and
> monitor the output temp. Now inject a regular can of R134a and start
> to watch the output temp. You might need two cans of R134a but once
> the temp gets in normal range stop adding freon. It is about normal
> for the low side pressure to be around 30 pounds or just slightly
> higher but always go by the temp and not the pressure. Of course if
> the temp didn't rise and you injected the one can or pressure around
> 30 something is wrong. Lastly label the system so everyone will know
> it's been converted. You will not want to add any R12 once this
> conversion has been done, only R134a.
> I purchased the R134a adapter that goes on the R134a freon can and an
> adapter found at the hardware store that converts the output of the
> R134a adatper to the standard R12 freon hose for about fifty cents.
> This way I didn't have to change the fittings on the vehicle and I can
> use my old R12 hoses and gage. This system has worked with no
> problems on at least a dozen vehicles I've converted over the three
> year period and my friends using this system have had no problems. I
> know some will object but once again, this info came from
> Interdynamics web site. Hope it helps others as much as it's helped
> me.
> wrote:
>> Hi folks,
>> I drive a 1989 Toyolla Corolla coupe, carbureted 4A-F with California
>> emissions, with 138k miles. I bought it used in 1999 with 94k miles.
>> It has a 4-speed automatic, original water pump, original radiator,
>> new thermostat, flushed coolant (last year). The belts are 5
>> years/40k miles old and look ok though squeak and sound rough
>> slightly for the first couple minutes when it's very cold (I live in
>> Boston). The newsgroups have helped me out many times with the car,
>> and I need your advice now yet again:
>>
>> Last year my car was running hot where the temp would creep up to
>> 80-90% of max temp all the time. The fan wasn't kicking in. My
>> mechanic replaced the Fan Switch (and thermostat at the same time),
>> and the problem was solved, and aftewards the car would always run
>> at 2/5 of its max temp, as it always did when newer.
>>
>> For the past month, I've noticed that the temp is constantly running
>> at 3/4 max when I'm driving past 60 mph, or past 45 mph and have a
>> passenger in the car. When I slow down, the temp will soon drop
>> down. If I run the heat, then the temp will also stay at 2/5 max,
>> which I think is where the car ideally wants to run. The temp does
>> not run high if I'm idling or driving at low speeds. The engine
>> runs fine. Bottom line is that when asked to do extra work to carry
>> a passenger or run above 60mph, the engine runs hot.
>>
>> The coolant/level color looks fine. The radiator and radiator fan,
>> from the outside, look like they're in good shape too and appear
>> clean and unobstructed.
>> What do you recommend I do next? I'm not sure sure how my mechanic
>> would know where to proceed. Options a
>> 1. get radiator flushed, see if this helps; radiator was flushed just
>> last year.
>> 1b. also replace hoses and see if this helps (hoses are original as
>> far as I know)
>> 2. replace radiator
>> 3. replace water pump
>> 4. replace radiator and water pump
>>
>> #4 should definitely do the trick, but would be pricey.
>>
>> --------
>> Other issues that have come up:
>> 1. rear struts rarely make groaning noises (usually happens as they
>> decompress as I'm getting out of the car)-- when I do the "bounce"
>> test they seem normal firm; the car's ride is fine; how urgent is it
>> to replace the struts?
>> 2. the clock went out yesterday-- could this signal an electrical
>> problem elsewhere? If the clock's an LED clock, which I assume,
>> then I would not expect it to go out..
>> 3. gas pedal yesterday started to make quiet groaning noises when I
>> step on it, like a door hinge that needs WD-40... where can I
>> lubricate it, and with which lubricant?
>> 4. A/C is weak right now, so hard for me to defrost the windows...
>> has anyone used "Freeze 12" or other R12 equivalents before? I
>> asked my mechanic about fixing the A/C but he said that it's
>> impossible to get a hold of R12 anymore (he did not mention the
>> substitutes) and that the only way to fix the A/C is to retrofit the
>> system. Thanks for your help!
>> John

Joey wrote:

> This way I didn't have to change the fittings on the vehicle and I
can
> use my old R12 hoses and gage.

That works, but for the insignificant cost of two 134a fitting adapters
it's a no-brainer to put them on. Then anyone who attempts future
repairs will NEED to use an r134a gauge set to tap into the system, and
hopefully use the correct freon as a result. Stickers are overlooked
and can peel off. Some people don't even care enough to read them.

Conversion adapters come in most if not all r134a conversion kits, and
are available individually. Just remove the schraeder valves from the
original ports before screwing down the new adapters.

The oil that comes in conversion kits (Poly Ester) is supposed to
smooth over the process of changing out your existing mineral oil for a
synthetic that works with r134a. While I tend to believe that Poly
does this better than PAG (normal r134a oil), I don't think either is
going to mix with mineral oil. I don't believe from experience that
either is going to necessarily destroy orings or coagulate with mineral
oil either. So I use the Poly at work after draining what oil I can
out of the compressor. I have had no problems with any conversions
this way. I would not use the Poly for special cases, like the Paseo
scroll compressor or the new Prius 110 volt unit. I would not use it
on certain GM and Ford compressor systems either.

End oil rant.

Toyota MDT in MO