HELP- radiator/coolant disappearing

m67tang

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The story,

Im adding about 3-4 quarts to the radiator every 100 miles. exhaust pipe is not showing goo or build up. i only have factory temp idiot gauge- not much to see there. the overflow tank is full from the radiator transferring into it. motor oil shows no coolant.

I've replaced the radiator cap. pressure tested radiator, it was ok. t- stat is oem and about 6 years old. radiator is plastic/aluminum about 5-7 years old.

where to look next?
 

hoodshauler

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Have you smelled your exhaust, just cause there is not any build up in it does not mean it is not burning it! I had this same problem with my 93 7.3 and it turned out to be the head gasket :(.
nothing coming out the exhaust but the smell.
 

Golden Helmet

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Have you checked your hose clamps? I chased a mystery leak for months because of a crappy clamp, don't know why but some days it'd seal fine (when I was looking for the leak), some days it would be just a slow drip, and other days it'd be almost pouring out (always when I had no time to pop the hood and look).

Also, try running it with no radiator cap on and look for bubbles inside the radiator. If you see bubbles, it's head gasket time.
 

shawn deere

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Ive heard of O rings in the oil cooler leaking when cold, but when it gets warmed up itll seal up.

In other news, i have a copper radiator sitting in a shop.
 

79jasper

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Ive heard of O rings in the oil cooler leaking when cold, but when it gets warmed up itll seal up.

In other news, i have a copper radiator sitting in a shop.
That would put coolant into the oil.
They can leak from the oil side and do that though.

Sent from my SAMSUNG-SM-G935A using Tapatalk
 

hesutton

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So the radiator is low, but it's pushing coolant into and filling up the overflow tank? When was the last time have you hauled something heavy? Does (or did) it cause coolant to spit out of the overflow when hauling?

How about a used oil analysis? Can tell you if there is coolant in the oil. Just because the oil isn't floating on a gallon of coolant in the pan doesn't eliminate coolant getting into the oil.

How about your water pump? Any coolant coming out of the weep hole on the bottom (really a PITA to see).

Heath
 

m67tang

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Not had an oil analysis done.
Not sure about the weep hole in water pump, I'll look in the morning.
The oil level is staying steady and looks fine too, so I don't believe I have co- mingling fluids.
All my load carrying is about the same: 800-1600 lbs. truck has a liftgate so even empty isn't really lightweight.
 

jwalterus

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I opened this thread wondering if you found the ******* that had "disappeared" your radiator :rotflmao
 

m67tang

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So here's my next question-
With 283k miles on a seemingly fine running engine--- if I end up needing head gaskets, should I just replace gaskets, or plan to pull the engine and tear down?
 

AcIdBuRn02ZTS

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If it comes to that... I'd do gaskets and have the heads checked over by a competent machine shop. These engines like to eat valve guides so would be best to fix it now if they have some play.

Loosing coolant from the radiator but overflowing the bottle is a common sign of head gasket failure or cracked head/block (more likely gasket assuming you've been running the right coolant/additives).

They make a combustion gas test kit for the cooling system that you can rent from most parts stores that offer tool rental.
 

m67tang

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If it comes to that... I'd do gaskets and have the heads checked over by a competent machine shop. These engines like to eat valve guides so would be best to fix it now if they have some play.

Loosing coolant from the radiator but overflowing the bottle is a common sign of head gasket failure or cracked head/block (more likely gasket assuming you've been running the right coolant/additives).

They make a combustion gas test kit for the cooling system that you can rent from most parts stores that offer tool rental.
I'm gonna be all over this tomorrow afternoon. I need my truck working again.
 
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