W210 E320 V6 running hot?

[fwb44]

The temperature needle on our E320 V6 W210 Elegance estate, 9/2000, 60K, FMBSH, sits consistently at about 2 deg. above the 'normal' line in the centre of the gauge except at 70 m.p.h. and over. Our trusty indy's diagnostics can't find any faults, original dealer who supplied & serviced the car to its only previous owner had no records of cooling faults & offered to send copies of all servicing invoices ... should we worry? When my old E300 TD W210 did this last summer I ended up with £1200 worth of repairs to the cooling system ... but now I'm being told 'petrol MBs run hotter than diesels'. True or false?

 

[nialler]

Hi FWB

I have the same year/model as yourself and the car temp runs between 83-90 and like your own drops below 80 over 70mpg. It may well be normal but I'll await an answer from someone with a bit more experience.

 

[jberks]

To be honest, provided it stays around 'normal' and doesn't get hot or cold the it's is fine and will do no damage. If it gets near the red then get concerned but if the fan kicks in and no problems occur and it warms up properly I'd leave well alone. I can't remember exactly where my 240 gauge used to sit, but it was fairly consistent and normal.

If you do have concerns about the cooling system, then the furthest I'd go would be to have the system drained and flushed to aid cooling and replace the thermostat to ensure it isn't cooling when you don't want it to.
If its getting cooler over 70, the possibly there is a small leak around the stat. Never had a problem on a Merc but Fords were notorious for this. The rubber seal would perish, allowing coolant to leak past the stat and it would take an age to warm up. I wouldn't fix it for the motorway aspect, but it may be worth sorting so it warms up as quickly as possible.

 

[fwb44]

the furthest I'd go would be to have the system drained and flushed to aid cooling and replace the thermostat to ensure it isn't cooling when you don't want it to. If its getting cooler over 70, possibly there is a small leak around the stat

Thanks for this, the car goes into service next week after LPG conversion so we'll keep a close eye on it

 

[Uncle Benz]

My old CLK320 W208 used to run above half way all the time. I was concerned initially, but, after some research I found a lot of V6 engines run at this level. I would not worry about it at all. If you read the handbook, it says it is acceptable for the engine to run up to the edge of the red on very hot days. E300TD w210 in my experience do run cooler on the gauge but I have seen more cooling probs on these than the petrols. It is possible to fit the fan belt incorrectly on these and it then runs the water pump backwards. The guy who had done this then removed the thermostat to try to cool it down and ended up in even more trouble!!

 

[fwb44]

I'll try not to worry about it. Stuck fast for 40 mins. in Knightsbridge traffic jam this afternoon with air-con on full to keep us alive and the needle on my E320 CDI crept up a few degrees ... but that I would have expected. Straight back down to usual below-median point as soon as we were moving again.