Coolant change on W202

[1998K]

I agree.
I would expect there to be a drain plug on the radiator underneath and on the block under the exhaust manifold on all Mercedes cars, no need to undo any hoses.
As also mentioned both drain and refil with the heater set to hot and the ignition on.

yes there is a plastic plug at bottom of the radiator plus a drain plug on the block, when Ive done this work on my 202 I was trying to open the plug into the block but some friend mechanic suggested me to leave it and to operate only with the radiator, to avoid leakage from the block plug!?

 

[1998K]

The job of renewing the coolant is so easy there is really no excuse for not renewing it every 3 years. Ron

I've still to understand why MB suggest to change coolant every 3 or 15 (yes 15) years, depending of the car

Does someone know something more

 

[Patronfrey]

Having had an alloy cylinder head (not Mercedes) corrode to the point where I had to have it repaired by alloy welding and then refaced I'm always cautious about keeping my coolant looking fresh. The corrosion inhibitors can become less effective with age (I understand). If the book says change it every 3 years I change it. A gallon of anti-freeze is a lot cheaper than having to renew a head-gasket - or worse!
Ironically, Vauxhall state in the Corsa owners manual that there is no need ever to change the G.M. coolant in my 1.2 8v Corsa. So I haven't and it has never given me any problem. Reliable to the point of boredom.
Ron

 

[Patronfrey]

yes there is a plastic plug at bottom of the radiator plus a drain plug on the block, when Ive done this work on my 202 I was trying to open the plug into the block but some friend mechanic suggested me to leave it and to operate only with the radiator, to avoid leakage from the block plug!?

Sorry, but I have to say I disagree with your mechanic. But then again I've never had any problems with leakage after doing the job. The thread on the plug will be a self-sealing taper thread and as long as you are sensible about retightening, and use a well fitting ring spanner, I can't see how problems would arise. A lot of fluid comes out of the block and if you do just the radiator you are renewing less than half of your coolant. What's the use of that?
Ron

 

[1998K]

thanks a lot Ron, I'm with you, in any case I'm quite sure that a lot of persons (I mean mechanics or DIY man) flush without opening the block drain plug.

But you are perfectly in the right way

PS: I've paid this coolant change as I delivered my used C270 few mounths ago, I really hope that they have done it in the proper way

 

[Patronfrey]

I hope they did the job properly for you too.
BTW - Wish I had a car like yours 1998K. I love my old C280, but if I ever change it (and eventually I must I suppose) the C270 CDI is the one I lust after!!! How do YOU rate it?
Ron

 

[Dieselman]

I've still to understand why MB suggest to change coolant every 3 or 15 (yes 15) years, depending of the car

Does someone know something more

Looks like a misprint. should read 3 or 5 years. Due to different inhibitors breaking down less quickly. They ALL break down with heat and age.

 

[Dieselman]

Vauxhall state in the Corsa owners manual that there is no need ever to change the G.M. coolant in my 1.2 8v Corsa. So I haven't and it has never given me any problem.

Just like MB say you dont need to change the ATF. well not until it's out of warranty anyway. ALL inhibitors break down.

 

[1998K]

Looks like a misprint. should read 3 or 5 years. Due to different inhibitors breaking down less quickly. They ALL break down with heat and age.

I've read also on this forum that value, I mean 15 years.

In any case 3 years is better in any case

thanks

 

[1998K]

I hope they did the job properly for you too.
BTW - Wish I had a car like yours 1998K. I love my old C280, but if I ever change it (and eventually I must I suppose) the C270 CDI is the one I lust after!!! How do YOU rate it?
Ron

thanks

I'm OK with the C270, it's an improvement over my previous W202 kompressor, in any case I never had any single problem on that car, sold with 145000km like new!
Hope also this new one will work well without problem.
Mine is avantgarde with sport chassis option, ride is a good compromise between well known Mercedes bootish ride and any other aftermarket set up (I consider too stiff the H&R and Koni I've installed on W202 to avoid dancing into the corner).
It's my first automatic gearbox and I really hope it will work without problems, since I'm reading some bad stories about this.
As far as consumption, it's really OK and you have always a good power (mainly torque) reserve.

But I've to be onest to say that, in any case, W202 internal cabin design is more like a tank and last much more any W203, this to be honest