brf29

Hi all, Im a long time lurker on this forum after purchasing my first car (96 c220) a year or so ago, i have just had it serviced (second time) and been told there is oil in my coolant (about a 5mm layer of golden 'scum' floating). i have been recommended a coolant flush to solve.

After trawling these forums it seems this is a semi-common issue associated with this model/year of benz and it could be/most likely is the head gasket leaking?? (some say radiator fluid but it looks like oil)

I had noticed the temperature gauge had slightly risen recently from my standard half way level but i thought that could be due to driving to a far warmer climate (im no mechanic haha)

I was just hoping for feedback on the possible issue, i can upload pics soon, i will drop it into another mechanic soon and keep everyone posted i just have been reading about $1000-2000 bills for replacing the head gasket which is gutting as i love my car but its been causing me some grief lately (just replaced lower front ball joints and front suspension)

optimusprime m1

The first thing i would do before any other, is have a pressure test on your engine.The garage can do this and its not expensive .They will have a tester that is fitted on the radiator , and it will tell them if you have a problems ie head gasket failure.

MTI

Yes, test should certainly be done to rule out the HG, but your description seems to lead the diagnosis in that direction. A gasket breach is allowing the compression stroke of one of the cylinders to send pressurized fuel and lubricant into the cooling journals of the block where it contaminates the coolant. Just draining and citric flushing isn't going to seal the breach.

brf29

Visual inspection by mechanic (merc/euro specialist), compression test to follow, he saw a small oil leak and tutted when he saw the coolant too, all signs point to head gasket and he sounds like he knows his stuff, bout 16hrs labour and hes getting all the parts skimmed/machined if ithats what the problem is, do it once, do it properly sort of fellow haha. hopefully ill fix this then it will be smooth sailing/minor issues for the next 20 years

MTI

Since the front of the engine is coming off for the gasket, give some thought to replacing the oil pump and water pump while you're there. I doubt that the twin row chain is anywhere near replacing, but perhaps the guides could be refreshed.

brf29

Cheers MTI, he said it looked as if the water pump has been done already, and he convinced me to stick with the current car as they are pretty reliable (he drives one too) i just need to see how much this is going to dent my wallet, haha might see if hes at all keen for a cheeky cash job

ptcruiser

"tutted". I love it..............So would Prince William :-)

brf29

Compression test complete, diagnosis: radiator replacement. Trans fluid in the coolant not oil?

optimusprime m1

In that case you will want a good flush out of transmision to clean it up before refill of the gearbox with ATF.

ptcruiser

What model and year?

brf29

its a 1996 c220

brf29

So i have it at the mechanics, they are rerouting the transmission fluid from the radiator so it instead goes through an aftermarket fluid cooling unit (typically used for automatic cars that do a lot of towing) this should hopefully eliminate the leak within the radiator

Keeping in mind im no mechanic and this is me explaining what was explained to me, saved like a grand on the job, worst case scenario i have to replace radiator anyway, in which case ill have 2x the cooling capacity (if I understand whats going on properly)

optimusprime m1

BRF then you will be ok to go .I will look in to the extra radiator to cool the oil from atf in my auto.

ptcruiser

To me, it would seem logical to replace the rad. It has already given you an indication that it is "crapping out" internally.
Replacement rads are not overly expensive.

js81

Bought my 96 C220 at 131k.... at around 140k, had to have the head gasket replaced. Previous owner let it boil over on the interstate when the water pump failed. Luckily, I too only had oil in the coolant, no coolant in the oil. Got it fixed to the tune of $1100 and the car has been mostly problem free since, save for an intake manifold gasket ($300 - bad vacuum leak, thought to be caused by the same overheating) and a new radiator (the oil that got in it basically killed it). Did the radiator myself; bought an aftermarket one online for about $75; keeps the car cooler than the original ever did, plus keeps all it's fluids inside - what more could you ask for?

Just turned 158k yesterday - has been solid for the past ~15k with only routine maintenance.