mckennar
New member
Installed a new radiator cap yesterday. The old cap had been "modified" slightly in that the rubber stopper was missing, so coolant was able to flow into the overflow tank at will with nothing stopping it/no pressure buildup.
While this hadn't caused an overheat event yet, I wanted to prevent it just in case.
So 340k...

PLUS new radiator cap...

PLUS
Possibly stock (not likely) definitely old radiator

EQUALS

Boom.
Drove about 5 miles before I realized this. Temp gauge never went above 1/2 way however I wasn't getting any heat out of the vents which is concerning.
Pulled over, emptied a warm gallon of water (been in the black truck all day) into the radiator (promptly leaked a lot of it out), drove about a mile home with the heater on. Heat coming out was almost too hot to keep my hand in front of it.
Let the truck run for another few minutes when I got home (kept feeding it water) and the temp needle never went up. No tailpipe smoke that I could see but I haven't run it since it cooled off.
The kicker is that I'd ordered a new KoyoRad radiator early-last week (so much for 2 day shipping, Amazon Prime...) and it isn't here yet... Really frustrating because this is a 183k mile engine I pulled from my wrecked truck and finished the install last week. The original engine from the truck was great but the crank pulley had turned the snout conical and destroyed the keyway and there was no going back from that.
Anyhow. Fingers crossed I didn't pop the head gaskets.
TL;DR If your top tank looks greenish-brown like mine, it's probably due to be replaced.
There's also a matching crack at the bottom of the tank that I'm pretty sure took the ATF cooler with it. Good thing I have a B&M installed.
While this hadn't caused an overheat event yet, I wanted to prevent it just in case.
So 340k...

PLUS new radiator cap...

PLUS
Possibly stock (not likely) definitely old radiator

EQUALS

Boom.
Drove about 5 miles before I realized this. Temp gauge never went above 1/2 way however I wasn't getting any heat out of the vents which is concerning.
Pulled over, emptied a warm gallon of water (been in the black truck all day) into the radiator (promptly leaked a lot of it out), drove about a mile home with the heater on. Heat coming out was almost too hot to keep my hand in front of it.
Let the truck run for another few minutes when I got home (kept feeding it water) and the temp needle never went up. No tailpipe smoke that I could see but I haven't run it since it cooled off.
The kicker is that I'd ordered a new KoyoRad radiator early-last week (so much for 2 day shipping, Amazon Prime...) and it isn't here yet... Really frustrating because this is a 183k mile engine I pulled from my wrecked truck and finished the install last week. The original engine from the truck was great but the crank pulley had turned the snout conical and destroyed the keyway and there was no going back from that.
Anyhow. Fingers crossed I didn't pop the head gaskets.
TL;DR If your top tank looks greenish-brown like mine, it's probably due to be replaced.
There's also a matching crack at the bottom of the tank that I'm pretty sure took the ATF cooler with it. Good thing I have a B&M installed.
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