Truck randomly pukes coolant

[TRAMPLINEMAN]

2014 2500, truck is randomly puking out coolant. Trucks been doing this for about a year now, but recently gotten more frequent. We’ve changed the cap, heater core, water pump and two thermostats(just because). It does it randomly, no set pattern. Yesterday it idled for around 18 hours and drove for 6 hours, no issues. This morning, drove it 2 miles and parked, puked out 2 gallons. The engine temp will get up to about 230 when it pushes coolant out. It never happens when we’re in it, we always notice it leaking from a distance and run to shut it off so it’s hard to tell if the fan is actually coming on. We’re planning on changing the fan clutch today. Any other suggestions?

 

[nukegm]

is the system actually building any pressure? do you have an infared thermometer so you can check the temp without relying on the gauge? and when it pukes, can you hear it boiling? cheers!

 

[SnoKing]

Sounds like fan clutch to me.

 

[TRAMPLINEMAN]

is the system actually building any pressure? do you have an infared thermometer so you can check the temp without relying on the gauge? and when it pukes, can you hear it boiling? cheers!

We’ve had a pressure gauge on the tank for about an hour now, hasn’t built an pressure yet. When it pukes, it empties the tank. Loosen the cap, and the tank fills with boiling coolant.

 

[TRAMPLINEMAN]

Sounds like fan clutch to me.

That’s on our list to change. We’re still searching for one locally.

 

[nukegm]

sounds strange to me - no pressure after an hour. also what comrade sno said. i would think the fan would come on as well....

 

[SnoKing]

AS a side note, I always have thought a clean engine runs better!!!!!

Maybe check and clean connections to coolant sensor(s).

 

[TRAMPLINEMAN]

Ok, I found the original cap had a ripped o-ring. New cap the spring cup in the cap is seized to the housing. Took o-ring from new cap and put on original cap. Next, I found the lower y pipe to be leaking. I never saw it before cause the coolant was spraying so profusely out the overflow that it was going everywhere. Now that the cap is working properly I could see the y pipe leaking. New y pipe should be here in about an hour. Hopefully that solves that trucks problems.