5.3 Vortec Coolant leak help needed

[UnclePeco]

2009 Tahoe 5.3 with 206k on it.

Leaking from "external coolant plug" below:

https://www.nookandtranny.com/Images/PagePhotos/LSxCoolantDrainPlugDiagram.jpg

Tried to tighten but could not get it to move. Any recommendations?

 

[horse123]

Maybe have to remove it, allow the coolant to drain, refill, and put some RTV gasket maker around the base of the plug?

 

[UnclePeco]

Sorry - wrong image. This is where it is leaking:

 

[gabriel9766]

Tht looks like part of the head.

 

[Merkava_4]

You might have to drain the radiator first and then apply thread sealant to the threads on the plug.

 

[UnclePeco]

Yes it is part of the head - will try to post pic from my actual car...

 

[UnclePeco]

This is an picture of my engine. Looks like a simple fix but access is tight and is feels really stuck. Open to suggestions...

 

[ls1mike]

I believe it is a port that has a plug in it. Could be used for a sensor. Probably needs thread sealer.
Try soaking it in pb blaster.

 

[jhellwig]

Are you sure it is leaking there? The heater hoses are above there and it could be dripping down.

Good luck getting it out. That area is a pain to get to. Might be worth taking to a dealer to fix.

 

[AntsinmyEyes]

do you have access to a cordless impact? an allen key socket with an impact could prob zip that right off.

 

[LeakySeals]

Originally Posted By: jhellwig
Are you sure it is leaking there? The heater hoses are above there and it could be dripping down.

Good luck getting it out. That area is a pain to get to. Might be worth taking to a dealer to fix.


+1. I just had to replace the quick connects. Hot coolant does a number on the plastic and they get flexed every time the plastic engine cover comes off.

 

[229]

It is likely the quick connects which can be removed and the heater hoses clamped directly to the aluminum heater core pipes.

If it is the plug then R&R with sealer. Check the acidity of your coolant as it may be time to flush. HTH