Symptoms
- Small drip or dried residue specifically at the weep hole on the pump's underside
- Coolant level dropping gradually
- Possible light staining trailing down from that spot
- May be accompanied by pump bearing noise as it worsens
Likely causes
- CommonWorn pump shaft sealThis seal is a normal wear item and, once it starts to leak, the weep hole is specifically designed to show it externally rather than let coolant enter the bearing.
- PossibleContaminated or degraded coolant accelerating seal wearOld coolant with reduced lubricating and corrosion-inhibiting properties can shorten seal life.
- CommonPump nearing general end of service lifeWater pumps have a typical service life, and weep hole leaking is often one of the first visible signs it's wearing out.
What to do
- Look specifically at the underside of the water pump, often visible from underneath the front of the car, for dried white or greenish residue or active dripping.
- Check the coolant level and top off temporarily while arranging a repair.
- Avoid ignoring even a small weep, since it typically progresses rather than stopping on its own.
- Listen for any developing noise from the pump area, which would suggest the bearing is also starting to wear.
- Have a mechanic confirm the leak is from the weep hole specifically rather than a nearby gasket or hose.
- Replace the water pump once weep hole leaking is confirmed, since this isn't a repairable seal on most designs.
- Flush and refill coolant properly after replacement.
Tools and parts
- Flashlight
Water pump and gasketSearch: “water pump for [make model year]”
When to call a pro
See a mechanic for water pump replacement once weep hole leaking is confirmed, since this reliably means the seal has failed and will continue to leak.
Safety
Generally low risk
Generally low risk for a careful person. Stop if anything looks different from what this guide describes.