[TRobinson6]

1. what is the normal operating engine temp

2. at what temp does the warning lite come on

3. is there a chime with the warning lite (like the emer brake)


sure wish Mercedes in their vast wisdom saw fit to put in a temp gauge like all other cars!!!

 

[jimvw57]

temp runs between 185 and about 195 from what I have seen. usually around 185 it starts backing down. No chime when it gets too hot, and when the hot light comes on, it is too late.

 

[Jo e Lefors]

I agree with jimvw57.
My 09 smart runs exactly the same temperatures mostly rock solid at 188. According to my ELM 327.
It will drift between 186 and 194. I have my warning alarm set for 215 degrees.
Gauges are nice, I love them.
Being a pilot, I'm in the habit of scanning my instruments and gauges often. Don't like driving vehicles without them.
I knew smart being an economy car didn't have any gagues when I bought it, so for $20 I added the Elm 327, I had an old smart phone I could dedicate as part of the package. Now I have more info about the condition of my smart while it is running than I will ever use, PLUS check engine light codes.
Take care.:smartje.bl.zl:

 

[TRobinson6]

I know the engine is toast when the light comes on but at what temp does it come on.....do I have 5 degrees above normal temp or 25 degrees?

 

[twcom]

I have the ScanGuage and watch my water temp. This week I see some issues with the water temp. In traffic I have creeped up to to 209 even saw a brief 220 one day. Didn't feel like my radiator fan was kicking on.

I trouble shot the fan all fuses relays and the fan its self seemed ok. I did the AC on Recirculate on heat on max and the fan kicked on fine. So now the fan seem to be fully functional again.

A bit low on coolant at just under the minimum line. The fan is kicking on at 213 and runs the temp back down to 185. Normal running seems to hold at 190 to 198. So I feel I am running kind of high. But now that the pressure is off, in that no need to dismantle the front end as the mechanics are intact.

Now when it comes to the radiator of the 451 smart. Is it inherently more complicated then cars of old where you flush the system, new thermostat, refill with antifreeze, even add a thicker radiator in the process. Or is there a more narrow scope of things to do with the 451 cooling system. I do see and electric draw through install, if nothing else there is space, would be insurance and may look cool with the bonnet off at the show and shine.

Have you customized your coolant system

 

[Miss Mercedes]

My smart has always run between 185-195 with the fan kicking on at 210-213 since new. Overheat temps start around 233 degrees, so I wouldn’t be worried about a fan that kicks on at 213.

 

[Smart Bob]

The red light will come on at 244 deg. F. At 246 deg. F, your engine is toast. The front fan will kick-on around 217 deg. F if the A/C is not on. Turning on the A/C on a hot day in slow moving or heavy traffic will actually bring down the coolant temp. If you are experiencing high coolant temps above 217 deg. F, turn off your A/C to reduce the load on the engine. I have had my 451 up to 233 deg. F on a day where the ambient temp. was 117 deg. F. It has survived these temps. and is running beautifully. Normal operating temp. seems to be around 194 deg. F, but it will climb up to 209-210 deg. F on a hot day in traffic. I wouldn't worry about it.

 

[twcom]

Well now I'm really intent on getting the coolant system tip top. That's a lot of plumbing. Not At all the old plug and play radiator upper and lower radiator hose. Gotta learn what I can before a visit to MB for a check up.

 

[jimvw57]

As you can see, the highest part of the system is the cylinder head and is usually where the damage occurs, and the most heat is generated. Make sure the air bubble is removed by opening the hose at B11/4 and make sure there isn't any air in there.

 

[TRobinson6]

I kinda disagree that the cylinder head is the highest point of the cooling system. If you raise the motor cover the engine is several inches below the cargo floor but if you take the hood off the coolant reservoir is above your knee level. Am I correct? So if that were the case if you cracked the engine hose and filled at the reservoir wouldn't that push any bubbles out?

 

[jimvw57]

The air bubbles will not go down below the floor of the car, but wil be trapped in the cylinder head until they have somewhere to go. Even pressure from the front of the car will not push them down below the floor to exit out the radiator. they will stay in the highest point on the motor.