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That head gasket actually looks pretty good to me. Have a closer look at the cylinder head, specifically at the block to head mating surface. Is there any corrosion visible in and around the coolant channels?
The reason I ask this is this:
I have been following this thread with some interest as I experienced a failed head gasket a couple of years ago on a B200F....or so I thought.
There was marginal loss of coolant that could not be detected externally. There was also a tiny oil leak to the outside near the oil gallery above the oil filter.
There was some evidence of overflow from the expansion reservoir's cap (if I had filled coolant up to the max. line on a cold engine).
There was also evidence that a previous owner had experienced high cooling system pressure as all hose clamps were tightened way too much, cutting into the rubber. I replaced many hoses.
Long story short: I drove like this for a year until oil started to appear in the expansion reservoir. I suspected #2 cylinder as it showed a dirty piston top on an endoscope while the other three were clean (indeed, exactly the opposite of what one would expect). I made an appointment to have a specialist replace the head gasket.
The day previous to the repair I made a long but uneventful trip. The morning of the repair I tried to start the engine but the starter motor would bog down. Water does not let itself compress like air, so I suspected over night water had seeped into cylinder #2. I removed the spark plug from that cylinder and started the engine which spewed the water out through the hole. Then I refitted the spark plug, topped up the coolant and drove to the shop.
They sent the cylinder head to be sand blasted and planed/skimmed but it turned out the water channels had corroded to the point that tiny channels had also formed in the mating area, running right under the head gasket. One found its way into #2 cylinder The head had to be replaced, as the corrosion went deeper than the head could be skimmed. This was not immediately obvious, but the sand blasting process revealed it clearly.
So hence my advice to check the cylinder head too!
By the way, yesterday I replaced my water pump because after a while after this head repair, there would be a tiny leak around the pump to head seal. This is not a unknown failure and apparently many keep driving like this slowly forming a sort of "coral reef" around it. It certainly didn't bother me and I postponed it until yesterday when I had planned to do maintenance anyway. I replaced it also because some play in the pump's bearings could be felt, which I didn't like.
You wrote:
"I think that the water pump gasket has failed because in 25 years it has never been changed, but I do not see how the two things could be connected, I mean, how does the coolant leak from the headgasket? How does it get there in the first place?"
This leak occurs on the pump to head seal, but that's not part of the head gasket but the rubber O-ring that sits in the pump.
The water pump I replaced turned out to be a Meyle branded part, which AFAIK is not a OEM pump, suggesting my 245 may be on it's third water pump now.
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1992 245 Polar B200F M47
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