how hot should it run?

[arizonaboxster]

Hey,

i was out in my 99 boxster today...when i noticed the temp guage was between the 250 mark and the unmarked one before 250. it's around 115 degree's in the sun (105 in the shade), a/c full blast. i shut off the a/c and turned the heat on high and it went down the the unmarked spot a bit right of the middle, in about 40 seconds, then i had to turn the a/c back on (was simply to hot), finished my drive home, and it stayed just a bit above that unmarked line.

should i be worrying? oil is clean, coolant is full..

[txhokie4life]

Hey,

i was out in my 99 boxster today...when i noticed the temp guage was between the 250 mark and the unmarked one before 250. it's around 115 degree's in the sun (105 in the shade), a/c full blast. i shut off the a/c and turned the heat on high and it went down the the unmarked spot a bit right of the middle, in about 40 seconds, then i had to turn the a/c back on (was simply to hot), finished my drive home, and it stayed just a bit above that unmarked line.

should i be worrying? oil is clean, coolant is full..

Seems to me that you are running hot.

Just to give you a datapoint -- when it was 107 here in Austin last week I was stuck in stop and go traffic and my coolant rose to

just to the right of the center of the 0 on the 180 mark. No where near where you are talking.

When I put the heater on for additional cooling, it moved back to the center or just left of center of the 0.

I'd have to check where I normally run -- but using my duramatic -- I've measured the typical 193, which I think is

closer to the 8 on 180 indicator.

This is an '00 3.2S that I rebuilt last winter. So all in all I'm pretty pleased to see it hold up to 107 degrees and

just sitting there after running about 80 down the freeway for 30 minutes.

I am using 0W-30 Brad Penn Racing oil.

M

[ericinboca]

Hey,

i was out in my 99 boxster today...when i noticed the temp guage was between the 250 mark and the unmarked one before 250. it's around 115 degree's in the sun (105 in the shade), a/c full blast. i shut off the a/c and turned the heat on high and it went down the the unmarked spot a bit right of the middle, in about 40 seconds, then i had to turn the a/c back on (was simply to hot), finished my drive home, and it stayed just a bit above that unmarked line.

should i be worrying? oil is clean, coolant is full..

Seems to me that you are running hot.

Just to give you a datapoint -- when it was 107 here in Austin last week I was stuck in stop and go traffic and my coolant rose to

just to the right of the center of the 0 on the 180 mark. No where near where you are talking.

When I put the heater on for additional cooling, it moved back to the center or just left of center of the 0.

I'd have to check where I normally run -- but using my duramatic -- I've measured the typical 193, which I think is

closer to the 8 on 180 indicator.

This is an '00 3.2S that I rebuilt last winter. So all in all I'm pretty pleased to see it hold up to 107 degrees and

just sitting there after running about 80 down the freeway for 30 minutes.

I am using 0W-30 Brad Penn Racing oil.

M

Just to add to the data points...in my '04 986S track car, a couple of weekends ago at Sebring International Raceway (florida), the ambient air temp was 100 while running on the track and the temp gauge was showing just to the right of the 0 on the 180 all day as I flogged it around the track.

115 ambient temp is pretty toasty, but yours sounds a little hot. Radiators all clean? Oil cooler functioning properly?

[GranburyChuck]

In Fort Worth here last week it was 105. In stop and go my temps rapidly went to the right side of the 0 in 180. The HVAC hack showed I was at 105C. Had it at the dealer for an alignment and also had them clean the rad's today. Temps seem better but it was only 90F today. Historically my car would run on the left side of 0 in 180 in good flowing traffic.

[Lyn]

I'm in Phoenix and I use my 2003S as a daily driver. It's been as high as 111 this week and sitting in traffic with the AC on, the needle sits just to the right of the 180 mark on the guage and it will move left back towards the 180 mark when I'm moving. I've got some leaves in my radiator area that I will be cleaning out this weekend and I expect that might let it run even cooler on these hot days. My 2 cents worth would be that if you're running close to that 250 mark, you need to figure out why before you overheat it.

Lyn

[txhokie4life]

I'm in Phoenix and I use my 2003S as a daily driver. It's been as high as 111 this week and sitting in traffic with the AC on, the needle sits just to the right of the 180 mark on the guage and it will move left back towards the 180 mark when I'm moving. I've got some leaves in my radiator area that I will be cleaning out this weekend and I expect that might let it run even cooler on these hot days. My 2 cents worth would be that if you're running close to that 250 mark, you need to figure out why before you overheat it.

Lyn

I'm guessing -- if its not the radiators being dirty -- check to make sure all the engine and radiator fans are working properly.

Sometimes a thermostat can stick and not open completely -- but I haven't heard that with these cars.

m

[arizonaboxster]

i'll def. have to look in to it.

[triguy46]

In Oklahoma, with days 100+ recently, 185 in traffic, down to 181 or so on the highway.

[Glyn]

Before you rush out and panic this could simply be a faulty temperature sender, if you were close to the 250 you would have boiled up.

Boiling point is 212 and for every pound of pressure the boiling point rises by 2 degrees, you have a 15 pound cap, therefore 242 degrees before boiling point is reached - If you had of boiled you would have known about it - my guess is the temperature sender is a little off track, simply replace it

[arizonaboxster]

i've had my share of blown headgaskets (used to work at a junkyard)....there was no boiling over or anything of that nature, it didn't smell hot either, no signs or indications other than the temp. guage. i don't think it's anything serious, but it's my "toy" so...it'll probably be a month before i even have time to look into it anyways.

[Stefan]

Start with the things that are easiest to diagnose.

The problem is likely one or two bad ballast resistors. With the car not hot, turn on the A/C and verify that both front radiator fans go on. If not, then that's the problem.

[txhokie4life]

Start with the things that are easiest to diagnose.

The problem is likely one or two bad ballast resistors. With the car not hot, turn on the A/C and verify that both front radiator fans go on. If not, then that's the problem.

If you can get access to a duramatic -- it can be used to individually turn on the fans.

m

[Glyn]

The ballast resistors control the slow running speed of the two fans, If the resistors had both failed then there would be no fans running until the temperature was higher than normal running temperature, then both would come on at full speed, however, with the air con on both fans run at full speed all the time, so i cant see that the resistor theory is correct.

Temperature control is achieve by the thermostat, the water pump and the radiators/fans, I have never heard of a Boxster having an issue with the thermostat failing but this is a cheap and easy part to swap out, The pump is clearly working and no water leaks suggest the system is sound.

If the car didnt smell hot, no boiling up and the only indication is the gauge then this points to either the gauge, or the sender, The sender is just a waxstat in that the hotter it becomes the resistance to earth diminishes, the unit slowly earths the circuit, full earth = full gauge reading.

[Loren]

The most common cause of thermostat failures in 9x6 series cars is pieces of the water pump impeller stuck in the thermostat. I have also seen a Boxster that was "overheating" and when we took the water pump off - all the impeller blades were gone (broken off).

[txhokie4life]

The most common cause of thermostat failures in 9x6 series cars is pieces of the water pump impeller stuck in the thermostat. I have also seen a Boxster that was "overheating" and when we took the water pump off - all the impeller blades were gone (broken off).

Weather it "smells hot" or not -- I would definitely look into this -- you've got a warning sign -- heed it -- HEAT is not your friend.

Even if all seems good, oil breakdown, engine wear, fatigue -- all are increased with elevated temps.

m

[arizonaboxster]

no worries, i fully intend on looking in to it prior to driving it again.

[arizonaboxster]

well i checked the coolant level, checked that the fans were kicking on with the a/c and they are. i took it for a 20 mile drive this evening, ambient temp of 100 outside, i ran it for about 13 miles with a/c set at 64, and the temp was between the 8 and 0 in 180, it started to go up a little to the middle of the 0 (and seemed to level off there) after about 13 miles, then i turned the a/c off, but left the blower going, but NOT heat, left it set at 64, a/c off, and it cooled back to between the 8 and 0.

i think it just needs a basic servicing.

Edited July 3, 2009 by arizonaboxster

[arizonaboxster]

there was quite a bit of crap (paper, dirt, misc..) in front of the radiators, i cleaned it all out and it seems happy now....

[palmtree907]

As an aircraft mechanic, I'd like to state that until you hit redline, its not "broken".Differebt scenarios will cause different things to happen (the debris blocking radiators for instance).

212 is the boiling point for a proper coolant mixture? Btw, thats another variable.

Should you keep an eye on it? Sure. I do that at 180. Would I panick? Not until it was approaching redline.

[JeTexas]

Mine never goes higher than this.

[Stefan]

If the resistors had both failed then there would be no fans running until the temperature was higher than normal running temperature, then both would come on at full speed, however, with the air con on both fans run at full speed all the time, so i cant see that the resistor theory is correct.

That's not quite true. The fans will go on high speed if the coolant temp is above 216°F or if the freon pressure is above 16 bar.

[txhokie4life]

there was quite a bit of crap (paper, dirt, misc..) in front of the radiators, i cleaned it all out and it seems happy now....

Glad to see it was

1) real

2) you paid attention

3) you figured out what was wrong and fixed it!

happy Boxstering.....

And as far as the Aircraft analogy -- they expect to repair/replace engines at regular intervals -- not what you expect

from a vehicle.

Also while the water temp might not boil off until > 212 degrees F, your oil viscosity will be affected by elevated temperatures

and this could cause more wear than non-elevated temperatures......

m

[Pierre's Porsche]

If you have a Boxster that's older than five years old, and you're beginning to run hotter than "normal," but not overheating, the first thing to do is clean out the radiators. A lot of debris gets caught between the AC condensors and the radiators there by blocking effective air flow. This is an easy couple of hours job that costs zero.