E220 124 Coolant loss & Compression figures

Omega

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Hi folks,

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
 

television

Always remembered RIP
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Your Mercedes
2002 SL500, 216 CL500, all fully loaded
Water pumps can and do leak. is there any white sludge in the oil filler cap or water droplets on the oil dip stick.

You could try a head sealer product, they get quite good reviews
 

Ellsy Tanners

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Have a look under the front carpets to the bear metal floor, for leaks inside the car, possibly from the heater matrix!!
 

wireman

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lancashire
Your Mercedes
nice 201 2.5D 1993 & very nice 129 SL500 1994
Examine your water pump when hot, cool/warm and cold, look around the drain hole in the pumps nose behind its pulley. I have found on some leaky cars that it has a drop or two of coolant on the pump first thing in the morning when the pump gland is getting worn.

The leak may be intermittent and only occur whilst running, if this is so the coolant will dry up before you get a chance to see it.

Only top up with antifreeze mixture, adding water will dilute your coolant untill the anti corrosion properties are degraded resulting in damage to the cooling system by rotting away from the inside.

I'd risk the cost of changing it if in any doubt since complete failiure of the gland is potentialy very costly.
 

HERBIEMERCMAN

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PRESTON, LANCS.
Your Mercedes
97. E300.TD. 7 SEAT.ELEGANCE. EST.TOYOTA SUPRA MK4. RS. VAUX. CORSA.GLS AUTO. SPORT.
hi omega, i agree with wireman and malcolm, another thing to observe is exhaust plumeing after say a 10 mile journey, once the exhaust system gets above "due point" there should be no plume (steam) unless you are combusting water from your cooling system ? you can also put a "falling pressure test" on, it is attached to your radiator, pumped up to the reccomended pressure and there is a "fall off graph" pressure decay by time to see if the integrity of the whole system is within acceptable limits. the test is quick and easy, the difficulty is locating the leak. one thing i have learned is that non of my cars ever need water or coolant ( on toyota i use "forlife") heats up quickly, cools quickly, antifreeze properties and stops errosion / corrosion. if you are consuming water or coolant somthing is wrong. i have used "wynns" rad seal, it's the best, can slow a head gasket leak but nothing will resolve a water pump seal due to shaft errosion. your cylinder pressures, don't know what they should be but no 3 looks suspicious. good luck. herbiemercman.
 
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