The other day my low coolant turned on. I stopped the car and checked the coolant level, it was low nearly empty in the overflow plastic bottle. I added water to get the coolant back into operating range. I also noted that the coolant was not a translucent green, but a milky brown color. That was disconcerting.

The next day the coolant was low again, and I added coolant and water. There also appears to be a coolant leak under and to the rear of the engine below the dist/cap, which can be seen from fluid on the engine block. There also seems to be oil present here.

Any ideas what may be contributing to this brown coolant?

TIA,
Lunchman, '95 Turbo 850

My S70 originally came with red coolant. A few years later I was low and added green coolant and it turned brown. Soon later I flushed the coolant and used all green coolant and it is now green again. But your problem sounds a little different being that you may have a leak.

If it's milky (indicating an emulsion) and brown I'd say your getting some oil into the water jackets in the engine block. Is there any white smoke out the exhaust? This would indictate that the engine is burning coolant as well, meaning coolant and oil are mixing both ways. I don't know about the 850, I've never had a head off one of these cars and I've heard there is no head gasket per say, but in every other engine I've worked on that would indicate either a blown head gasket or a cracked head. In either case you might see some external leakage of oil and/or coolant somewhere on the motor itself. All in all it's not a good thing, either case would require at least a new head. Hope that no damage was done to the bottom end of the motor by excessive coolant in the oil, which would mean a whole new engine. I would get someone to look the entire engine over pretty quickly.

Sounds like manifold gasket. Start saving your pennies.
--
98 V70Rawd(101Kmi), 95 854T(85K mi), 88 245(165K mi)

Isn't the radiator connected with an oil cooler radiator and transmission cooler? The brown and burnt stuff could be a leak between oil cooler and radiator.

A few more details:
The car does not have any lost in performance from this leak into the coolant. The oil and transmission fluids look fine, and are not low.

Another related issue is that coolant is boiling and overflowing thru the grey coolant cap. I will be replacing with green coolant cap.

Thanks,
Lunchman. '95 850 Turbo 135,000

My 850 was the same way when i bought it. I cleaned out the coolant track by following the VolvoSpeed instructions (vinegar/water solution, running for 5minutes and repeat, see the site for mixing e/t/c) and then added fresh coolant and has been fine for 2 years (flushing next week because i feel its due)