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At 215000, my venerable W210 has been slowly leaking coolant. I've checked all the external plumbing and found no bad hoses. I'm seeing no white smoke, no rough idle, no oil in coolant or foam in oil. Latley however, I have noticed a line of moisture along the cylinder head: Red line indicates moisture/glisten.
and what look like evaporated coolant stains on the manifold below.
Am I looking at a head gasket R&R coming my way? Would Blue Devil or another diesel-specific additive buy me some time or effectivley fix what seems a slight problem?? Any experience with these additives or recommendations? Any light will be appreciated! Thanks.
The engine in your picture is clearly not a US '97 because they were NA. I have a '97 with a head gasket coolant leak. Mine started about 7 years ago. I added just enough Barrs radiator stop leak to stop the leaking. Every year or two it would start leaking a bit, and I would add a bit more. This past fall I started on my second bottle after I put in a new radiator due to a cracked plastic tank, along with new coolant.
This is the same ground up root that has been used for coolant leaks for probably 50 years. It is quite unlikely to cause problems unless your heater core or radiator is plugged enough to be marginal. Zerex, back in the '60s was adding it to their antifreeze and advertising it as leak preventing antifreeze. I understand that they stopped because people didn't like the brown stuff that settled out of their antifreeze. Barrs makes a wide variety of stop leaks, but the only one I have experience with is the radiator stop leak variety. I view it as maintenance. If I see coolant on the garage floor, I add an oz.
If you indeed do have a head gasket that is bad, then most likely the coolant travel downwards. Not upwards. Normally, on hot engine, coolant evaporates due to engine temp unless you have fairly big leak. I do see, from time to time, that have a bad radiator or hoses that leaks and gets blown to wherever due to radiator fan kicking in. And even this, more than likely it's a fairly big leak. With that been said, how often do you add coolant and how much?
Usually, small radiator leak is hard to find, unless it's a big leak that leave a puddle on the ground. Front leak is easy. The side that's facing the engine is rather difficult due to fan and all other stuff in the way. Whatever coolant you have, offending area should have evaporated coolant trace, Whatever color coolant you use, been green, pink or brown, it should have the tell tale trace of the coolant. Look for these.
If the leak is small enough, I'll recommend what neibur said. Just put radiator stop leak or there's several that's made for head gasket, although I don't have any experience in those. Are you planning to keep the car until it falls apart? then I suggest the actual repair, although the cost of repair probably will be more than the the car's worth. Been a diesel, the head is huge chunk of steel, not like the gasoline counterpart.
Trying to get another ~5 years out of the old girl. I like the comfort and mileage running bio/renwable diesel. By that time, full electric may be viable for my budget.
That is the one I used, and the only one I have experience with. Few folks on here will remember the old Barr's Leaks that was a bunch of pellets in oil in a glass bottle. That was the same ground up root in pellet form, that dropped to the bottom of your radiator. Some was always mixing into the coolant over time. I don't like the idea of so much junk in the cooling system, so I just added a few oz. and ran it about a half hour on the freeway to plug the leak. The particles get hung up in the leak and build up sort of a clot. The expansion of the aluminum head on the iron block will eventually mess with the clot and it will start to leak again. When that happens I just add another oz or two. Our cars do not have a radiator cap, so getting it into the circulating coolant is a bit sketchy. The coolant tank is pressurized so I pour the stop leak into the tank and hope it falls down into the circulation. So far it has seemed to work.
Your picture has a turbo which yours does not have if yours is a US version. You should have a crossover pipe from the EGR contraption. I have had mine about 15 years and do most of my own work. My nearest dealer is about an hour away. Of course there is likely no one there that has ever worked on a '97.
Thanks for your info, Nelbur. Same same for me trying to find an experienced mechanic. Diagnosis/Troubleshooting is a dying art, I think, in this Brave New World of codes and timesheets. Unfortunately I have no space and not enough lower back left to do more than change fluids and filters myself. I'm just about up to pouring things out of bottles (I do that nightly in fact) so I'll give the Bar's a try. Continued good luck to you and your "classic" as well.
Just as a quick followup, the seepage around the valve cover appears to be just that; oil not coolant or exhaust outgassing. A single application of Bar's seems to have adderssed the slow leak, with no thermostat or heater core issues to date (1 month on).
Bar's has a wildly extended product line. This is the one I settled on:
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