Losing coolant (video) 86 350

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Challis350

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Hey all

Drove from Seattle to Vancouver, BC over the weekend. Was rather alarmed to see the expansion tank empty when I arrived. Re-filled up rad with coolant, started engine, only to see lots of coolant escaping underneath.

As it was 33/91 degrees this weekend I was watching the temp gauge like a hawk whilst driving anyway and nothing alarming happened.

See video below:

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Does anyone with experience here know of a likely culprit? It looks like its coming from the rear of the engine bay somewhere.

Please forgive the oily underneath. Truck has been very slowly leaking oil since i bought it 9 months ago and i haven't cleaned it.

Thanks
 

82sbshortbed

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Freeze plug leaking? Temperature gage plug on side of head leaking?
 

TX87R10

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I can't tell exactly the location but you should be able to follow it up and I'd bet a dollar it is a rusted out freeze plug. For me it was hard to track because my freeze plug that was leaking was blocked by the motor mount or something, but I could tell it was from right there and I felt the freeze plug.
 

Rickf

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Get some of the dye and a black light, or an inexpensive radiator pressure test kit. There are freeze plugs in front of the flywheel, after further review check the intake gasket at the back of the heads.
 
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SirRobyn0

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If it's coming out of the bellhousing most likely it's a freeze plug. But the video it looks like it's running off the tranny, so maybe the back of the intake manifold leaking externally.

Most certainly your going to need to do some looking to find the source.
 

Challis350

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Thanks all - Will get underneath it this weekend. Just useful having some common suspects before I sit climb under an engine dripping boiling coolant.
 

Challis350

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OK this was simple in the end. A hose was projectile squirting out coolant to the rear of the engine which made it look like something more serious. All good now.
 

SirRobyn0

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OK this was simple in the end. A hose was projectile squirting out coolant to the rear of the engine which made it look like something more serious. All good now.
That can happen. Remember if one hose is gone and the others are the same age it might be cheap insurance against another hose failure to replace them all. Thanks for replying back and letting us all know what the issue was!
 

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