Does anyone know what the normal operating temperture is for the engine when you look at the heat gauge on the left side of the dashboard? I recently
had a 'coolant level' warning come up on the dash,and obtained some 50/50
Prestone and it seemed to have solved the problem. However,warnings like that,I must admit,had me a little paranoid when I see 90 degrees on the gauge. Now I know an engine is going to generate heat,but am I worrying too much? Thanks to all who reply

 

My '96 E320 temp gauge shows 97-98 C during summer, and about 95 during winter... It's been like that for a long long time

 

mine usually stays around 80 and runs like rabbit on the track for almost stock

 

in extreme cases (where temperatures can reach up to 50C) my car shows 99C but then again it doesn't go any higher than that

 

I see mine run at about 90 in the summer heat, and a tad higher than 80 in cooler weather.

 

mine is always just above 80 but ive only had it 2 weeks

 

Don't worry. My E320 averages 90C but has reached as high as 99C when pushing the car in hot weather.

 

I may have a problem as I am now seeing my gauge go to 120c repeatedly over the last few days,and early this morning, I'm seeing steam coming from
the area where I put in the antifreeze ,and the 'Coolant Level' message on the dashboard. This is ,of course ,a leak somewhere,so my question is this, did anyone here have a similar situation,and what might have been a possible remedy:change of hose,replacement of the antifreeze reservoir,or what I fear the most,replacement of the radiator. Thanks again to all who reply....

 

If the steam is coming form the reservoir area and there's no obvious leak, I suggest replacing the cap as a first step. If the cap no longer holds pressure, the coolant boils and escapes through the cap, eventually causing the car to overheat.

 

The normal operating temperature of the car when we got our 2002 E320 when it was new was around 90 degrees, even in hot weather, it would stay just slightly over 80 degrees. After the dealer replaced the coolant, the temperature fluctuated a bit more.

Now, after the dealer has replaced the coolant, the car's temperature seems to go as high as almost 99 when the car is sitting in a lot of traffic. I've expressed this to my service manager and even asked for a coolant flush and replacement, but he says this is fine and normal and told me to keep my money and not to worry.

Naturally, since 100 degrees is the boiling temperature of water and it's coming close to that, I'm still slightly worried about me burning off all the water in the radiator. So, whenever i'm sitting in traffic and I notice the temperature is rising considerably, I turn on the front window defogger (or is it defroster). This makes the coolant temperature go down considerably and fairly quickly. However, on a hot day, this means I am baking inside the car.

 

Yeah,Pat ,I guess it's a toss-up as to who's boiling ,you or the ride...

Lex,your observation is dead-on,I ordered a new cap ,and should be getting it
later today. But today,prior to driving to work,I put some 50/50 anti-freeze in ,closed my existing cap tightly,and the temperture never went above 90 degrees on a 20 minute highway jaunt. Go figure??? Thanks for all your replies!!

 

A 4 cyc toyota stays 50/50 all the time ..... what gives !!!

 

95-99 degree is OK... My '96 E320 has been like that during summer for over three years. If your coolant is a mixture of 50/50 water/ethylene glycol, then its raises the boiling point of your coolant to about 107C when no pressure,,,, but under normal operating , your engine is about 14-15 psi, that means now the boiling of your coolant is about 107+25 or 132 C... so if your gauge is 95-99 C it's still way below the boiling point of your coolant... and that's the reason why your radiator cap is so important, if there is a leak, it will lower the internal pressurew and hence boiling of your coolant... This is all about science guys

Happy motoring

 

You should be using either the M-B coolant or Zerex G05 (Valvoline version of the same). It's essentially the hybrid Organic Acid Technology coolant that is different from the standard ethylene glycol (aka green coolant) and the Dex-Cool (aka long-life 'orange coolant')

The M-B alloy engines require a different pH level coolant compared to the standard green coolants that have been around a long time. The wrong coolant can cause corrosion or 'pitting' within the cooling passages inside the engine and cooling system.

Another tip is after refilling or topping off the system, the thing to do is set the temp control to the highest setting and drive until its completely warmed up (fan on low). Once you do that, the air is "burped" out of the cooling system.

It avoids having the gurgling noises that might result in the heater core.

 

You may also need to replace the thermostat, It may not be allowing enough coolant through to cool the engine properly. I had to on mine.

 

So far I got the cap replacement,and I have to get a radiator flush to replace the Prestone with the Zerex G05 I got yesterday. Any idea of the price of the thermostat?? I'll go to my 'people' and see if it's available,.and if
I find it,i'll post the price

 

I had the thermostat replaced a couple of years ago at the dealer. I think it was well under $100.

My temp guage is at 80 for most of the year. It goes up to 85 or so in the middle of summer.

 

I got mine here. http://catalog.eautopartscatalog.com...Thermostat+Kit

My mechanic said it sucked to install though.

 

Thanks for all your replies to my dillemma,I really appreciate each and every one of them. Gettting back to said dillemma , I had the aforementioned flush done yesterday,and after replacing the anti-freeze,and running the AC/Fan,as suggested above,the temp gauge remained high,and my guy believes I may need a pump (Damn!!) Any agreements or disagreements with that diagnosis?? If I didn't love this bucket so much,it would be in the used car lot.......

Update:the thermostat and the water pump are a shade under $250,so that's not bad at all.

 

Ruffrob : Something fishy about "thermostat + water pump = around $250 " ... It's almost impossible. I just replaced my water pump (priced $ 750 at dealer, part + installation, but I selected a local guy for $700, not because of the price, but this local shop is close to work and coolant, airconditioning are all they do, and they really know their stuffs and I have my other cars done by them.

The part for '96 E320 water pump is around $375 alone, and its location is a pain to get to, that's why the labor is high

 

CC,check here,www.thebenzbin.com,I''ve bought from them a number of times,and NEVER had a problem. Not everything about our cars has to be a bank breaker....

 

ruffrob

If you have the time and know-how then you can save lots of money...Have fun

 

Thanks for the overview,CC. The problem has been solved by the dealership,it was a faulty thermostat,along with a worn belt on the fan behind the grill. Parts and labor total:$305 tax included.