VZ SV6 Leaking coolant

[CommiodoreVZ]

Folks, I have a similar problem with our 2 x VZ V6 3.6's, after considerable diagnosis I was able to locate the Inlet housing "o" rings are a common fault with all 3.6VZ's, this along with the serpentine belt has far to much tension on the water-pump from the tensioner, 34lbs is what kills the water-pump housing bearings.
buying the OEM water-pump replacement at least comes from Mexico, not China as does the original water-pump. The thermostat housing on the rear of the engine does cause headaches when trying to replace but do it cold and be careful when removing the intake Pleneum as you can rip the gasket, break it free while the engine is warm then let it cool off before reaching out back to replace, non OEM original thermostats are available 1/2 the price of genuine GMH

 

[Mufudzi]

The problem is caused by the inlet housing O rings. I had a similar problem bought some O rings off ebay. I have made a video on how to replace the O rings when i replaced mine. Here's the link https://www.youtube.com/watch?v=Q7RaWB4OgQ4

 

[Sloth_n@med_Speed]

Hey so old thread, but...
Just replaced the thermo, water pump and all gaskets, o-rings and seals, and all was working fine. I checked all worked areas after every drive till I was confident no problems. Until home from work this evening, and when I turned off the car, coolant came pouring out underneath. Opened the bonnet and it's coming from the heater valve(?). Had another good look around the engine, and it's definately the only leak.
Is this a serious problem? And any idea how to fix?

 

[Trevor loves holden.]

replace it.

 

[rambunctious]

Simple to replace, clamp each side and vacuum hose.
I always use a little Locktite number 3 gasket goo on the hoses for added safety.
Make sure you have it going the same way as the existing one.
Available from most good parts outlets.
https://www.bing.com/search?q=heater+tap+vz&go=Search&qs=ds&form=QBRE