Coolant smell at front of truck

Blue 04 Z71

New Member
Jan 31, 2016
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I noticed a pretty strong coolant smell coming from the front of the truck. It seems worse when the e fans are running. The radiator is a used one from a 03 SS. Water pump had new gaskets put in at 97k and I'm at 130k. I don't see any leaks and it's not being mixed into my oil. It's only in the engine bay. Any ideas? Should I just put a new water pump on there since it's the original from 04?
I pressure tested the cooling system for 20 min and the gauge didn't move. The radiator does have some cracks starting and there seems to be some seepage at the bottom corner. I also found that the drivers side water pump gasket is leaking a little.

I looked up some water pumps and there are 2 ac Delcos. 252-845 and 251-743 is any difference between the 2 besides the price?





Not sure what happened here. It must of been this way when I bought it.


Circled the spot I think is seeping
 
Last edited:

dszx13

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May 28, 2014
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You check the heater hose connection at the firewall? That's a common leak area


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dszx13

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May 28, 2014
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If you put a pressure test on it, you would see something. What did you have it set at? A pinhole leak may take awhile to see. I had to let a envoy sit for a couple hours the other day to find it


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Blue 04 Z71

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Jan 31, 2016
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If you put a pressure test on it, you would see something. What did you have it set at? A pinhole leak may take awhile to see. I had to let a envoy sit for a couple hours the other day to find it


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I had it at 14 psi for 20 -25 min at least.
 

Blue 04 Z71

New Member
Jan 31, 2016
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The 251-743 is the OEM stuff vs the 251-845 which is china. I went with the OEM stuff. Hopefully it lasts as long as the original.
 

ScottyBoy

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Apr 6, 2012
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You check the heater hose connection at the firewall? That's a common leak area


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its prolly coming out of the weep hole on the pump, and evaporating before it even hits the ground.

I have had my heater hoses leak at those plastic quick connect fittings, and I had my water pump fail exactly this same way. I smelled coolant and I didn't see any visible leaks, yet I was losing about a quart of coolant every 3-4 weeks. I FINALLY discovered that it had a slow leak at the weep hole on the water pump.
And then those damn plastic quick connect fittings got brittle over time and started seeping coolant out. As soon as I touched one of them it cracked clean apart and gushed hot coolant everywhere. And since I have a Suburban with the rear heat, I have "T" fittings on mine that needed to be replaced as well. I finally got them all replaced with new Dorman fittings from Rockauto.