Coolant leak, suspecting water pump

[sonerick]

05 V6 with about 110k miles on it.

I did some maintenance work this past weekend (oil & filter, radiator drain-n-fill, etc.) and noticed the coolant was low in the overflow tank (almost near the bottom). Seeing all of the V6 HG failures lately makes me a little nervous. The spent oil looked fine though, and the coolant that I drained from the radiator looked and smelled good, so I'm hoping (fingers crossed) that it's not a HG issue. I popped off the radiator shroud, and the radiator looks fine. No visible leaks from any of the coolant hoses. I did notice some pinkish-white residue behind the water pump pulley.

I haven't had any cylinder misfire CEL's yet, so I guess my next steps will be to pull the spark plugs and check them out (they were fine at about 90k when I changed them). I'll probably get an oil analysis done the next time I do an oil change too.

For those of you with a V6 that have had the water pump fail, where did it leak from? How did you diagnose it? Where did you see the coolant residue?

If it is the water pump, I'll probably do the repair myself because it doesn't seem that hard. Is there anything else I should replace while I have it apart (fan clutch, etc)? I've already replaced all of the idler pulleys and tensioner pulley due to bearing noise, and the belt looks good (only about 35k on it).

 

[Sungod]

Before my head gasket blew on my 93, my reservoir was dropping constantly and I couldn't find any leaks. It was driving me crazy. Then one day my temp gauge went crazy and I had a plume of white smoke billowing out of my exhaust. If yours is dropping, it has to go somewhere. I hope yours is a leak. You should be able to notice the anti freeze odor in the engine compartment if there is a leak and it is evaporating off. Otherwise you should see it on the ground.

 

[4RNNR]

When I had a water pump go, I noticed I was loosing coolant, but I didn't see it coming out the tail pipe, so I didn't think it was a head gasket

I also knew I had all new hoses, and that wasn't the problem

You can get a tool (or swing by a shop for the test) that basically fits on like your radiator cap does, and causes pressure

the pressure shows where the leak was

In my case, it was around the very bottom side of the water pump

Hope this helps

 

[sonerick]

Thanks, I *hope* its a leak too. I thought I may have smelled coolant on a few occasions, but thought nothing of it and assumed it wasn't my vehicle. Come to think of it though, it could have been me, and since I can see some pinkish residue around the water pump I'm leaning towards that.

Pressure test is a good idea. If it is in fact a HG though, wouldn't that cause problems and force more coolant into the engine?

 

[4RNNR]

I would like to hear from others on that particular question, but I would think if you haven't noticed any discoloration in your oil, or smelled a funny smell from the exhaust that it's not a head gasket thing ...

 

[Sungod]

Thanks, I *hope* its a leak too. I thought I may have smelled coolant on a few occasions, but thought nothing of it and assumed it wasn't my vehicle. Come to think of it though, it could have been me, and since I can see some pinkish residue around the water pump I'm leaning towards that.

Pressure test is a good idea. If it is in fact a HG though, wouldn't that cause problems and force more coolant into the engine?

A pressure test will show if you have a leak. It really could be anywhere. It could be the radiator, heater core, a hose, a pump, etc. A leaking head gasket that allow coolant into the combustion chamber its the greatest for compression. I would probably do a compression test first to see if it is holding. Then pressure test the cooling system. I probably wouldn't start it if the pressure test fails unless I could see the leak. At least I would pull the plugs and turn it over a few times just to be sure. That might be a little extreme, but that would be the safest way.