Pulled into my garage today and the temp guage hit the last line before the red. I thought it was running a tad hot so shut her off and popped the hood and coolant was spewing out the overflow tank. There are no leaks that i am aware of.

Any help appreciated! Could an air lock have caused this?

 

Possible but unlikely. It just sounds like it over heated. Most common issues is a stuck thermostat or a fan not coming on. Step one would be verify those are working. After that it starts to get ugly.

It is normal for cars to get a little hotter once the water pump stops pumping. Engine will reach its hottest point about 2 minutes after you shut it down. It is best to try to get them cool before you shut down but with a stuck thermostat there is not much you can do.

 

I did a coolant change a few mo ths ago, along with replacing the thermistat. I therefore doubt its the thermistat. The fans are definitely spinning.

While i was doing the coolant change, i removed the battery to unplug the low coolant sensor as it was on and the coolant wasnt low. There was a small puddle of coolant on the overflow where the hose goes to the radiator. I dried it up and havnt seen the puddle return.

I also had a tk block test done on it by a mechanic before i did the coolant change as there was white stuff on the oil cap and i was concerned of a blown head gasket. The test came back fine and the mechanic saidit was probably because it had been sitting for a long time.

 

test the radiator cap, look for leaks in the hose that runs from the radiator to the reservoir including the connections at each end.

 

Pretty sure there are no leaks in the tube, is there any way i can remove the metal part of the tube to inspect that?

Im wondering if i didnt have the rad cap turned far enough, how far around am i meant to turn it? The arrows have faided on the cap. Am i safe to fill it up with tap water temporarily?

 

I had the same thing and it was the radiator cap. I had one of those caps with the lever on it. Every time I shut it off, coolant would overflow the tank. I put a regular cap on it and have not had the problem since.

 

Had the same issues with my 3.4, replaced the lever cap with a normal one and it was fixed. Also just had a f250 come to me with the same issue, also the same fix.

 

Wow I have not seen a lever style cap forever. I think they are used on cars before we had overflow. Back in the day radiators where higher then the engine. There was a refill point on the radiator. If you filled passed that point the radiator spit the coolant out on the ground. Those caps where not designed to allow coolant to flow back into the radiators like a modern cap.

FYI most thermostats that fail, fail in the first 6 months of service. Infact I have seen Sooo many new stats fail I will only use a fail safe stat in my cars. Fail safe thermostat will stick open if it fails. It could be a bad cap but if it is not you are playing a game that could get very costly. Water is fine short term.

 

Thanks for your responses.

Filled with water, bled and replaced rad cap. Have driven around and problem hasnt happened again so have drained and filled with coolant. Am just praying it doesnt happen again..

Just a Q regarding bleeding, according to the notes i have read, after filling you should run engine with rad cap off, and add coolant as needed. Issue i have is as soon as the t stat opens, all the coolant just starts comming out the radiator so i end up just putting the cap on and using the bleed screws.. Am having no heat issues now. Needle sits at a quarter highway, goes just above half in heavy traffic

 

check coolant level in radiator when cold, maybe after setting overnight. if its full to rim your good to go.