mystery water leak

[MaxIcon]

I just fixed a problem like this on my 99 C70, which has been a pain lately. It had the same symptoms you describe for a while, and I could never find a leak with casual checks.

Finally I topped it off, drove around to get it hot, then poked round under the hood, and it turned out I had a small crack high up on the coolant overflow tank. It was hissing and spitting, but not enough to cause water to actually drip (or it was evaporating before there was enough to make a puddle). I figure it was losing most of the coolant while driving, when the levels sloshed up to the crack.

It looked like someone had whacked it while doing some work on the car - there was a discolored spot with some crazing on the plastic, and some of the crazing had extended into cracks all the way through.

Cash is a bit short after some other expensive car work, so I repaired it with multiple layers of JB Weld, after lightly sanding the area around it and cleaning it with alcohol. The first layer cracked and developed a much smaller leak, so I put a few more on, which have held up fine for several weeks. If I were to do it over, I'd knead the JB Weld into a fabric patch for the first layer, then put a few more layers of straight epoxy over that.

The tank's not that expensive ($50-60), but this looks like it'll hold until my cash flow recovers.

[volvee850glt]

I had coolant in it but most leaked out so its just water now but its been pretty warm here for a while. But when it was cold here I made sure there was always coolant in it.

[VolvoTurbo850]

If the front plastic cowl is installed you will never see the leak. Remove it and inspect the lower hose to see if it is spongy looking. One advantage of the green stuff is that you can trace the leak. Also check the petcock (drain plug right beside the hose).

The other thing on these cars is that the opening to the upper hose sometimes cracks. You usually cannot see it unless you remove the upper hose. Depending on the size of the leak, it is possible for the fluid to slowly leak down the side of the plastic wall of the rad and eventually evaporate.

I always use the cardboard idea too to trace it. It is also worth looking at the radiator fluid reservoir tank and see if anything is dripping down that towards the front of the wheel well.

[polskamafia mjl]

I just fixed a problem like this on my 99 C70, which has been a pain lately. It had the same symptoms you describe for a while, and I could never find a leak with casual checks.

Finally I topped it off, drove around to get it hot, then poked round under the hood, and it turned out I had a small crack high up on the coolant overflow tank. It was hissing and spitting, but not enough to cause water to actually drip (or it was evaporating before there was enough to make a puddle). I figure it was losing most of the coolant while driving, when the levels sloshed up to the crack.

It looked like someone had whacked it while doing some work on the car - there was a discolored spot with some crazing on the plastic, and some of the crazing had extended into cracks all the way through.

Cash is a bit short after some other expensive car work, so I repaired it with multiple layers of JB Weld, after lightly sanding the area around it and cleaning it with alcohol. The first layer cracked and developed a much smaller leak, so I put a few more on, which have held up fine for several weeks. If I were to do it over, I'd knead the JB Weld into a fabric patch for the first layer, then put a few more layers of straight epoxy over that.

The tank's not that expensive ($50-60), but this looks like it'll hold until my cash flow recovers.

Did anybody pay attention to this? Try this. Kee It Simple Stupid. KISS

[MaxIcon]

Cash is a bit short after some other expensive car work, so I repaired the cracked expansion tank with multiple layers of JB Weld, after lightly sanding the area around it and cleaning it with alcohol. The first layer cracked and developed a much smaller leak, so I put a few more on, which have held up fine for several weeks. If I were to do it over, I'd knead the JB Weld into a fabric patch for the first layer, then put a few more layers of straight epoxy over that.

OK, bumping an older thread with a repair update.

The JB Weld held up OK for a while, but cracked again last night with a big cloud of steam. It seems it just couldn't hold up to the flexing of the tank over time and constant pressure changes.

The tank had developed more small cracks, and I just ordered one a few days ago, so the timing was good on that one. I patched it again last night with more JB Weld, and it's doing fine today, so if it holds until the new tank arrives, I'll be good to go.