Hi Everyone! Thanks in advance for any insight you might be able to provide! So, a couple weeks ago, I had a catastrophic failure of the coolant bleeder valve, which led to a loss of coolant and overheating which melted the thermostat housing. Rebuilt the POS coolant bleeder valve out of brass, and replaced the thermostat/housing and expansion tank as the sensor had not worked since I purchased the vehicle. The last two weeks, it appeared as though the problem was solved as I drove the vehicle extensively, over mountain passes and off-road, with no further loss of coolant and engine is running well and getting good gas mileage with no hints of overheating....until yesterday. Yesterday, I got a low coolant warning and checked...it was about 2-3 cups low. And now I'm seeing coolant dripping while engine is running under the passenger side. I have not had the opportunity to get in to the engine bay yet, but hope to later this evening.

My question is: are there any common points of leaking from that side of the engine other than the water pump? Any advice on things to check are very welcome! Thanks!

 

Maybe the heater core coolant lines. Especially if rear HVAC is installed. I believe those may run under the wheel liner or very close to the well before they shoot back.

 

Update: I took off the engine cover and upper fan shroud to get a better look, and all looks good up top, however, I can see where the coolant is pooling in the bottom, center of the engine top the skid plate.

 

Well, remove skid obviously. Check oil cooler.

 

It is likely the waterpump. For some reason if there is a decent overheat event they seem to go shortly after.

 

I do believe the waterpump is the culprit. Took off the skid plate and the front of it is saturated with coolant. Looking up as best I can, it does seem to be coming from fairly high up behind one of the pulleys. I'm guessing the seal on the waterpump has failed.

 

Well, I replaced the water pump, and it no longer leaks while not running (previously it dripped constantly), but once I start the engine, there is a steady drip of coolant coming from somewhere still. Could this be a characteristic of the coolant hose that leads to the back of the water pump area and to the coolant bleeder valve? Any ideas of where to look next are much appreciated! Thanks!

 

So, took it apart once more, and found the o ring had been torn. Seems like the one included with the AC Delco water pump was a little loose and got caught when I first installed it. Went to Napa and found a suitable replacement, and it's working perfectly... No more leaks! Hooray!