Need help locating a coolant leak on 3.4

[shaguar_red]

Hey guys. I am chasing a coolant leak. Before I tear it down, I wanted to see if anyone had an idea where this was coming from. At first I thought it was a freeze plug next to the water pump, but it appears the leak is coming from ABOVE the freeze plug. I cant see where because the accessory bracket and altenator are in the way. Any ideas? here's some pics..

[Mad Max]

Re: Need help locating a coolant leak on 3.4

This is unlikely, but it looks like it might be coming from your timing cover, or most likely - from your intake manifold water passage and running down the front of the engine. If I remember correctly, this is a common problem.
Oh, the heater hose runs somewhere around there too. If this is a mulitport injection, the heater hose comes off the front of the manifold and runs through that accessory bracket. Might want to check that. I've seen pinholes in hoses that spray a good distance and confuse you as to where the juice is coming from.
More qestions than answers - sorry.

[shaguar_red]

Re: Need help locating a coolant leak on 3.4

This is unlikely, but it looks like it might be coming from your timing cover, or most likely - from your intake manifold water passage and running down the front of the engine. If I remember correctly, this is a common problem.
Oh, the heater hose runs somewhere around there too. If this is a mulitport injection, the heater hose comes off the front of the manifold and runs through that accessory bracket. Might want to check that. I've seen pinholes in hoses that spray a good distance and confuse you as to where the juice is coming from.
More qestions than answers - sorry.

Well I rented a radiator pressure tester lastnight and pumped the system to 19psi and couldnt see a hose spraying anywhere. Manifold or timing cover are something I need to look into. Ive ruled out the hoses. I wish it was a hose..Those are easy to fix. :cry:

[3.4grapeofwrath]

Re: Need help locating a coolant leak on 3.4

Am I seeing things or is that a crack on top of the water pump housing?
It might just be a casting seam.

[shaguar_red]

Re: Need help locating a coolant leak on 3.4

Am I seeing things or is that a crack on top of the water pump housing?
It might just be a casting seam.

:omg: Good eye! Ill check that out at lunch!

[shaguar_red]

Re: Need help locating a coolant leak on 3.4

Am I seeing things or is that a crack on top of the water pump housing?
It might just be a casting seam.

Whew.. no crack, its a seam. And its not the intake, the leak starts lower than that..

[tkoforpresident]

Re: Need help locating a coolant leak on 3.4

i'm guessing heater hose connection into the LIM. the plastic ring inside gets fudged up pretty quickly. i bet it's dripping down the front of your engine.

[shaguar_red]

Re: Need help locating a coolant leak on 3.4

i'm guessing heater hose connection into the LIM. the plastic ring inside gets fudged up pretty quickly. i bet it's dripping down the front of your engine.

Yea thats what I was thinkin, i saw a lil green up there. How do you fix it?Does that pipe pull right out?

[tkoforpresident]

Re: Need help locating a coolant leak on 3.4

there is ONE bolt below the metal pipe holding it on. you can probably pull and wiggle it out, but it will be stuck in there good. I ordered a new pipe from gm partsdirect. it came with a plastic o ring in it and i haven't had any leaking problems yet.

[Mad Max]

Re: Need help locating a coolant leak on 3.4

As I remember, that pipe is a PIA to remove. I don't remember what the seal is - a neoprene o ring on the plastic clip? Team Guinea is probably right. New hose from GM will fix problem.
What I usually do - go to the local high pressure hand car wash, wash the poo out of the front of the engine, then pull out in daylight and look for the leak. You usually can see the approximate area pretty quick, or exactly where it's coming from.
Good luck. Post the results when you figure it out. :tup: