As the title says, I have a coolant leak coming from above the freeze plug. the freeze plug its self does not get wet it just goes around the plug. Also the leak is not coming from the head. It's an older renix model 4.0. Has anybody had this problem? The PO for some reason was dumb enough to only put water in the cooling system for the winter. None of the freeze plugs seems to be popped out or leaking but when I got the jeep I had to replace the thermostat housing. any help is appreciated.

 

I would get some brake cleaner and a wire brush. Spray and scrub the area clean and then dry it. Check for a possible crack and or the area around the frost plug. If no sign of anything then start it up and watch the area. Also look above that area for a possible drip from above. Water in the winter is not good. I have a block in my scrap pile that has a bad spot that oil actually soaks through. It was a factory flaw in the casting and who knows this could possible be similar but in a coolant passage. Just a guess....

 

ok, thanks for the suggestion Ill try that. This jeep is in the desert now so winter should be much more kind to it here.

 

Dried it, cleaned it, observed it. Its definitely leaking from above the freeze plug. I put my dry finger on the exact spot while it was running and it got wet within 30 seconds. Obviously the water isnt pouring out but its enough that I'm worried. also my water pump gasket is bad so there's that.

 

I'm wondering if that's where what little was left of the water the PO put in it settled and rusted through all winter. I sure hope not.

 

I hate to say it but you may as well pull the intake and exhaust manifold and get a better look at what your dealing with. If it is a crack or a seep spot it's gonna be time for a different engine.

 

It doesn't look good for you. It does sound like you may have either a crack or worse it rusted through like you think. Good luck!

 

That's what was creeping around in the back of my mind I was just hoping someone had something else. I needed to weld up the exhaust manifold anyways. Maybe its time to swap in that chevy 350! mwahahahaha!

 

Thanks for the help anyways!

 

Go for it. My buddy just got his 88' out one the road this week after installing an older 304 out of a CJ in it. He's sitting on a 3.5 inch lift with 32' BFG's and now sporting dual exhaust and a crap ton of power. It lights the tires right up with no issues. Custom made headers. EFI unit on top and a cool little custom mad braket for the AW4 TPS. It's pretty cool.

 

Aghhh that's awesome. Know of anyone that swapped a ford 351 in? I kinda have one laying around.

 

Nope not sure on that. Google it and see what comes up.