Chevy 5.3 head gasket leak, any familar with this?

Ok, so if it’s not one thing it’s another. I changed out the water pump a month or so ago to resolve what I was told was a leaking water pump. I took the truck in for an oil change over the weekend and they said I have a coolant leak, and showed me where it was. They said it could be the water pump seal or the head gasket.

I dried off the top of the block right behind the water pump where it looked damp and then started the truck and could see it get damp again over a couple minute time frame of the truck running. I did it again just to confirm. It is in fact leaking from the head gasket, not the water pump.

With that being said….what is the recommended course of action? Drive it for a while until as it is a slow leak? Get all the gaskets replaced, I assume that is $$$? New engine from the junkyard?

I have read that some people don’t recommend doing the head gasket without checking things in the bottom end as well….thus why the new engine option was listed.

How many miles?

162k. 2001 Suburban.

Just getting broken in.
That’s a fairly common issue with those motors. If you leave it, I would VERY CLOSELY keep an eye on the oil and coolant for contamination. Otherwise order OEM gaskets and stainless bolts, find an engine machinist in your area and have them cleaned and inspected for flatness and cracks and you may need him to remove a couple broken manifold bolts. Flatness can usually be fixed, cracks can’t. Be prepared for potentially buying new/remanufactured heads. Reinstall everything with antiseize and proper torque specs.

I don’t think you have any choice other than repairing the engine. If you want to up grade you are talking major $$$$. You are going to have to repair it to sell it any way. Besides you will get to look at most everything topside when you repair it.

Gundy

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find an engine machinist in your area and have them cleaned and inspected for flatness and cracks and you may need him to remove a couple broken manifold bolts. Flatness can usually be fixed, cracks can’t.

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Does the engine need to be pulled to do this?

Why do they need to be inspected for flatness, cracks? There has been no overheating, just a very slight leak that might have been there for the past 1-2 years. I have always had a slow coolant leak, just not sure if it’s always been the headgasket, or if the water pump was actually leaking.

Pretty sure a few of the manifold bolts are broken from what the oil change guy told me.

early 2000’s ls motors have also had a few issues with cracked heads….. ive personally seen 2 different tahoes that got head gaskets and were still using coolant… pulled heads again and had them tested and founds cracks….. just a fyi, have them checked before you put them back on

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find an engine machinist in your area and have them cleaned and inspected for flatness and cracks and you may need him to remove a couple broken manifold bolts. Flatness can usually be fixed, cracks can’t.

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Does the engine need to be pulled to do this?

Why do they need to be inspected for flatness, cracks? There has been no overheating, just a very slight leak that might have been there for the past 1-2 years. I have always had a slow coolant leak, just not sure if it’s always been the headgasket, or if the water pump was actually leaking.

Pretty sure a few of the manifold bolts are broken from what the oil change guy told me.

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There is a TSB on the Castek heads from that year and engine developing cracks. I have a pdf file of it but have no idea how to post it. Getting it checked is just so you don’t need to pull it again if it the gasket doesn’t fix your issue. If you can visually see it is the gasket by all means slap it back together with new seals and bolts.

No the engine should not need to be pulled, there should be plenty of room to work in that ‘burban.

Its a big job. To do it right both heads should be done. 10 plus hours of labor if you go the shop route. To take a stab parts and head work $500 plus the labor. So 1500-ish if a repair shop d does the work.

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If you can visually see it is the gasket by all means slap it back together with new seals and bolts.

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I can visually see the leak. It’s right behind the water pump and I can watch it get damp/wet when the truck is started. It’s a slow leak……

I am familiar with the TSB, but I have not checked the heads yet to see who the manufacturer is.

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If you can visually see it is the gasket by all means slap it back together with new seals and bolts.

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I can visually see the leak. It’s right behind the water pump and I can watch it get damp/wet when the truck is started. It’s a slow leak……

I am familiar with the TSB, but I have not checked the heads yet to see who the manufacturer is.

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Go buy some AC DELCO coolant leak tablets and crush them to a fine powder Then Pour them into in your radiator when coolant is warm and run your truck,
920 miles or so)…. if your leak is small enough it will seal that leak.

The Ac Delco tablets will not clog any heater core tubes !!

I have seen many small coolant leaks stopped with them