'02 Impala 3.4L, 80K: Sudden Coolant Leak

[Colt Hero]

Unbelievably, I'm on the road and just noticed a small pool of coolant under the car!!! I ran the car at idle, and sure enough, after about 5 minutes, a plume of coolant shot up briefly and was followed by a steady stream falling directly downward. Looks like right behind the water pump - if that's the water pump sitting up top and front. I assume it is, since the hose coming from the bottom of the radiator connects to it (and the power steering pump is clearly located behind this pump, toward the firewall side)

Anybody change a water pump on these cars? I've got no manuals or tools with me, but I'll buy duplicates if it's not a big job. Of course I could take it to a mechanic, but WHO? I'm in southern New England. I probably could hobble back to my point of origination (1000 mi) by pouring in coolant along the way, but that would only work if the leak did not get worse along the way...

[maxwedge]

Originally Posted by Colt Hero

Unbelievably, I'm on the road and just noticed a small pool of coolant under the car!!! I ran the car at idle, and sure enough, after about 5 minutes, a plume of coolant shot up briefly and was followed by a steady stream falling directly downward. Looks like right behind the water pump - if that's the water pump sitting up top and front. I assume it is, since the hose coming from the bottom of the radiator connects to it (and the power steering pump is clearly located behind this pump, toward the firewall side)

Anybody change a water pump on these cars? I've got no manuals or tools with me, but I'll buy duplicates if it's not a big job. Of course I could take it to a mechanic, but WHO? I'm in southern New England. I probably could hobble back to my point of origination (1000 mi) by pouring in coolant along the way, but that would only work if the leak did not get worse along the way...

If it is the water pump it is fairly accessible on that car, that said do you have the tools with you to do it? Water will do just to get home, but if it is pouring out, I don't think so.

[Colt Hero]

Well, first I have to see the leak from underneath to verify where it's coming from. Right now, I'm assuming it water pump-related because the stream is falling directly behind the pump. The stream is very similar to (sorry for the analogy), a urine stream. But when the car takes off, it forms a line on the ground about 3 feet long, then dots a bit, then seems to stop, so it might only be leaking on startup or shutdown (if that's possible). The overflow tank hasn't seemed to go down much either. So, I wouldn't say it's pouring out...

One other thing to mention: Just prior to this trip, I poured a tiny bottle of radiator dye into the radiator. I've been suspecting a leak, so I thought upon return I might be able to see the dye on the block or in the oil when I change it next. Could the dye have helped cause the leak, or is this purely coincidental???

[maxwedge]

Originally Posted by Colt Hero

Well, first I have to see the leak from underneath to verify where it's coming from. Right now, I'm assuming it water pump-related because the stream is falling directly behind the pump. The stream is very similar to (sorry for the analogy), a urine stream. But when the car takes off, it forms a line on the ground about 3 feet long, then dots a bit, then seems to stop, so it might only be leaking on startup or shutdown (if that's possible). The overflow tank hasn't seemed to go down much either. So, I wouldn't say it's pouring out...

One other thing to mention: Just prior to this trip, I poured a tiny bottle of radiator dye into the radiator. I've been suspecting a leak, so I thought upon return I might be able to see the dye on the block or in the oil when I change it next. Could the dye have helped cause the leak, or is this purely coincidental???

Dye is not the problem.

[Colt Hero]

Turned out to be a very easy replacement. Four bolts on the pulley, 5 bolts on the pump itself, release the tension on the serpentine belt. Only problem I had was with removing the old gasket remnants from the block. Use a razor blade, then a Brillo/SOS pad, but it took forever. The old pump apparently failed with coolant running out the bottom "weep" hole. Bearing/shaft and unit in general appeared to be OK otherwise. Replacement pump was $32 at AutoZone with lifetime warranty. Took me several hours to replace, but next time I should be able to do it in about an hour (not counting setup and cleanup).