E220 (124) Coolant loss & Compression figures

[Omega]

Hi folks,
1995 E220 124 Petrol Auto Saloon

I seem to be losing/burning water from the cooling system.
I can’t find a leak & had supposed the head gasket might be at fault (101000 mls) tho’ she runs as sweet as a nut.
Oil (full synthetic) is o.k.
Plugs are o.k (changed them yesterday to Iridium ones). They looked perfect in colour & gap etc.
I also took a compression test whilst I was at it.
To me it ‘looks’ within tolerances, but you guys will know better.
1 = 180,,, 2 = 175,,, 3 = 165,,, 4 = 185 pounds.

I know the gasket is about ready to replace at the usual 100k mark,,,, but as I say, she runs really well.

Consumption is slightly low in comparison with my previous cars – at just under 30, but has been since I bought it 5 years ago.

1/ any idea on water loss ?
2/ are my pressure readings within tolerance ?

thanks for reading this folks

 

[grober]

There's a pretty sensitive test which some garages use to "sniff" the air above the coolant. I think they use an exhaust gas analyser to pick up traces of combustion gases in the coolant. Supposed to be a good predictor of head gasket failure. Coolant loss should always be investigated because of potential damage to the engine. Water pump failure is another favorite-look for a drip at the drain orifice on the underside of the pump if its the original MB one. Relatively easy to change on the 4 cylinder car

 

[Omega]

Thanks for a rapid reply Graeme,

I'll have a look under the pump today & will call my local MB dealer tomorrow to ask about the coolant check.

Will post any results on here.

Baz

 

[bolide]

As Grober says, I'd suspect the water pump before the CHG. It's also possible to get tiny pinholes in the radiator that weep very slightly

I'd try parking the car up after a run with newspaper under it to see if you can find a leak

Nick Froome
www.w124.co.uk