07 lucerne 3.8L water pump

2007LucerneCXL · May 9, 2021

A full system flush is probably a good choice if it's never been done or previous history on maintenance is unknown. Here's some diagrams on the system which may help. On the heater core it's #44 and there are older post on R&R but from what I remember on the post the entire dashboard needs to be disassembled so it's something that should be confirmed.

paul8539 · May 9, 2021

Contrary to what Mad Coachman said, pullys HAVE gone bad on me, twice. Caused a belt to freeze, and with no belt turning the water pump, it was not working, and that was causing the overheating.

Mad_Coachman · May 9, 2021

paul8539 said:
Contrary to what Mad Coachman said, pullys HAVE gone bad on me, twice. Caused a belt to freeze, and with no belt turning the water pump, it was not working, and that was causing the overheating.

So you're the exception. I guess I should have said they "rarely go bad".😎

“Goals” · May 9, 2021

2007LucerneCXL said:
The hose that is near the engine is the input to the heater core, not sure if it's required to go the same direction. If not done yet this may be a good time to replace the plastic elbows with metal ones and thermostat if needed.

The other item if the heater core is good and no air in the coolant system is the actuator(s) on the interior may be bad or is hung up for the lack of heat on a side.

I was able to run water through both ports of the heater core. Everything seems to working ok at the moment. Will check back in if things not looking well. Thanks for the dashboard picture as well. Major help!!!

2007LucerneCXL · May 9, 2021

Hopefully all will work out with no problems, good luck on getting it finished.

spellman1989 · May 9, 2021

2007LucerneCXL said:
Hopefully all will work out with no problems, good luck on getting it finished.

When I run water the hose through the heater core what do I look for exactly? Never done anything like this before

2007LucerneCXL · May 9, 2021

Once the coolant is out it should be clear, but on any vehicle there could be some sediment that may also come out. It's kind of how much or how little has been done maintenance wise over It's history.

Tazz48 · Jun 2, 2021

spellman1989 said:
Oh OK thank you! Also where would I find a new pulley? All the auto parts store here don't have them in their system. Or is the old pulley reusable?

I got mine from a junk yard look brand new

Tazz48 · Jun 2, 2021

Mad_Coachman said:
Your pulley is probably just loose or your water pump is REALLY bad.
There's a good reason that auto parts stores don't stock the pulley. They don't go "bad".

Sorry but they do go bad they get hot plus the pulley is plastic

Mad_Coachman · Jun 2, 2021

Tazz48 said:
Sorry but they do go bad they get hot plus the pulley is plastic

The pulley is metal. More Information for ACDELCO 19367394
Read the description.
Material: STEEL

You are thinking of a tensioner pulley which can be either plastic or steel.

Tazz48 · Jun 2, 2021

Mad_Coachman said:
The pulley is metal.

Not the water pump pulley. I think I would know I just had it put on last week

Mad_Coachman · Jun 2, 2021

paul8539 said:
Contrary to what Mad Coachman said, pullys HAVE gone bad on me, twice. Caused a belt to freeze, and with no belt turning the water pump, it was not working, and that was causing the overheating.

I think you are referring to the belt tensioner pulley.

Mad_Coachman · Jun 2, 2021

Tazz48 said:
Not the water pump pulley. I think I would know I just had it put on last week

Wow...I guess they really "cheaped out" after the series 2 engine. Can you post a link to this plastic pulley? Prove me wrong.

More Information for GM GENUINE 19367394

Tazz48 · Jun 2, 2021

Mad_Coachman said:
I think you are referring to the belt tensioner pulley.

Do u have a northstar engine

Mad_Coachman · Jun 2, 2021

Tazz48 said:
Do u have a northstar engine

The title of the thread says