I just replaced a radiator that had a failure of the top tank seal. The problem started with a slow loss of coolant with no evidence of leaks, until the top seal failed. Replaced it and thought all was good. Details here: https://www.yotatech.com/forums/f116...ceable-230295/

I replaced the radiator on Saturday and verified there were no leaks. Today (Tues), the temp gauge went a bit over center going back to work from lunch. It took almost 1/2 gallon of coolant to top it up. Still no visible leaks.

So, am I looking at a blown head gasket after all?

Facts:

I replaced a leaking exhaust manifold gasket when I replaced the radiator 3 days ago.

About 3 years ago, the engine overheated when a brass fitting blew a pinhole leak and let out the coolant.

Before I replaced the radiator 3 days ago, I checked the cylinder compression: each one pumped up to about 120 psi after about 4 cycles of the engine. The rear most cylinder's plug had a thin bit of wire between the electrodes, like it had burned/welded electrode material to make the wire that was shorting it. The exhaust manifold leak was at that cylinder.

There are no visible signs of coolant leaks.

There is no noticeable smoke or steam from the exhaust.

There is no water in the oil and no oil in the water.

Edit:
Truck is an Xtracab, 2WD, 22RE, about 150k miles, single owner (me), only previous engine work is timing chain guides and water pump.

 

Did you drive it and then re-top off on Saturday? You can fill an engine but if it is cold and the thermostat is cold (closed) than there will be air in places that won't work out until you have gotten it up to temperature and (after cool down) topped it off again. I wouldn't be scared of head gasket issues unless it does it again or you see milk on the dipstick or steam out the back.

120 psi seems a little low but depending on your mileage it might be fine.

 

I only drove it about 6 miles on Sat after the swap, but time enough for it to get up to temp, and the level seemed OK then... I think. I did drive it about 20 miles on Sun and another 18 or so on Mon. All without checking the coolant level (mistake). My worry is that now, with a new radiator with no leaks, I seem to be back in the slow loss mode. I guess I'll just keep a close eye on it in the next few days.

 

Hard to see and leeks slowly, the heater pipe behind the water pump drivers side??

sure would be nice to find out it's not the head gasket.


Repo

 

Timing chain wore a hole through the timing cover?

 

Seriously doubt that. No water in the oil. I changed the timing chain guides and chain at around 50k miles. Top one was broken, could hear the chain slapping side of the the cover. Haven't heard any similar sound since the guide replacement.

Thanks for the ideas so far, guys.

 

You might need to "burp" the coolant. Need to get your truck on an incline (Hood being the top) The steeper the incline, the easier to burp. Rev the engine till it overheats. Repeat as necessary. Also Search "Burp Coolant"

If that isn't the problem, it could be that your water pump went bad....

 

"overheats"????
No thanks. Haha.
Inclines do help. But if you manually pump the large hoses, it seems to move the coolant around pretty well.

 

I was a bit leery of the incline thing too... all the oil might run out from the old rear main seal!



/It's a joke. The rear main seal is so bad the oil would run out. Oh, well...

 

I've Inclined 2x and had no problems. :jessica:

 

I think it was the overheating thing that got most of them....

Park on incline, run HEATER till the cab is overheated, put more fluid in once cold.....

 

UPDATE: To anyone who might still read through this thread, it was the head gasket blown between a cylinder and the water jacket around cylinder #4 the water jacket around #4 was completely clogged with carbon buildup from combustion gases.