Tiny coolant leak at head gasket

2001, 5.9 liter V8, 180,000 mi
It has this tiny coolant leak. Left bank near firewall. Its the coolant leaking to the atmosphere. No evidence of coolant in oil and #7 spark plug looks fine. Not even enough to drip or leave a trail. I can smell it when getting out after driving it, and can just barely see a mist when warmed up and idling. When I drove every day (about 250 miles/week) I would have to add 1-2 liters of fluid every month. Would rather not replace the head gasket if I can avoid it. So:

  1. Would it help to re-torque the head?
  2. Any thoughts on the radiator stop-leak products?


I retorqued the head on my 2.0L Chevy Cavalier engine - it stopped a small leak, but I don’t remember if it was oil or coolant. I’d try that and see how it goes and hold off on stop-leak products. Good luck and please keep us informed.

That leak sounds like a good problem for stop leak.

I looked on Rockauto, and the gaskets didn’t look like mls . . . so therefore I’d retorque the head bolts first, rather than trying stop leak

The head bolts on your engine are Torque-To-Yield head bolts.


Attempting to re-torque the head bolt can over-stretch the head bolt making the leak worse.

Add a teaspoon of black pepper to the coolant.


Just from memory I don’t recall ever running across a coolant leak at the head gasket on a MoPar engine but I do recall a couple of 318s leaking at freeze plugs and one had a hair line crack at the freeze plug perimeter which only leaked when hot and only steam then.

So of course I don’t know what’s wrong here but that’s my 2 bit guess. A close inspection is needed and that can be tough on a hot engine.

and the “MoPar engines” I referred to were just old American iron including the slant 6, 318s and 360s.

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I had an early 318 that leaked coolant into a cylinder, but it was the earlier “polyhead” engine which was a wider crossflow head. Nothing like a 360. More like a 325 Dodge non hemi.
They were all solid lifter engines and I over revved it racing a kid with a chevy. It had steel head gaskets that had not blown out anyplace but the leak stopped when I used what looked like and asbestos composition gasket set.

My thoughts are that if this truck is still in decent condition body-wise (no rust or collision damage) and the transmission still shifts properly, it is worth a proper fix. If you can DIY, the proper fix is well worth it; even if you have to pay a shop to do it, it’s still borderline worth it. In case you aren’t aware, trucks hold their value really well, until they become rusted or beat to hell. A new truck can easily cost $50k or more.

Just do it the right way–change the head gaskets, have the heads checked and resurfaced at a minimum (I would also have the valves re-ground and new valve stem seals installed) and of course use new head bolts. If the engine has ever overheated, or if any stop-leak product was ever added, I would also replace the radiator and water pump.

I would, too, but first I’d try tightening the head bolts, even if they are TTY. It might do the trick and the downside is that it might not. And you have only one head with a problem.