2.4L overheating
 

Hi everyone, just swapped out 2.4L engine for another used one. After swapping it seems there is something wrong with the cooling system. I brought the car to a mechanic to have the crank learning procedure done for the new engine. It was towed, so I don't know if the problem started before it got to the shop. The mechanic test drove it after the crank learning and said the temp shot up.

I've never had problems with the cooling system before, and it rarely ever showed temps above the 1/2 mark on the gauge. I figured it was a bad thermostat and left with the car. 2 miles later the temperature was climbing and as I pulled over to shut it off the red light for extreme heat came on.

Checked a few things, radiator fans both on. Has all new dexcool, tried running with the coolant reservoir cap off to cycle air bubbles out, didn't seem to keep the heat down. The radiator is cool to the touch. Also the heat in the car doesn't work and doesn't seem to cool it down, just blows normal temp air. Any ideas?

did you try flushing the radiator out? make sure you don't have a clog somewhere...

I'll try flushing the radiator. Are there bleeder plugs for coolant on the 2.4L engine? I tried getting any air bubbles out by running the car with the reservoir cap off, seems like it was burping but I'm not sure if that's how it's done. Thanks for the ultra-fast reply!

To bleed you leave the cap off and let it warm to operating temperature from cold. Squeeze hoses and stuff and rev the engine a little to try to get things worked through.

The heat not working sounds like the heater core got clogged.

If the radiator is staying cool you want to look at the thermostat being stuck or water pump failure.

Replaced the thermostat already, forgot to mention that. Will a garden hose have enough pressure to flush the radiator and heater core? Can the engine be flushed with water? I'm wondering if it isn't the engine since everything worked fine with the cooling system until the engine swap..

water pump

I don't know about the engine, but if you put a garden hose up to the heater core and stomp on the hose to build some pressure that'll do it, just switch back in forth from inlet to outlet a few times till nothing but clean water comes out.

Tried flushing, getting air bubbles out, nothing worked. Brought it to my mechanic and he said he's almost 100% sure that the engine has either a bad head gasket or the block is cracked. Apparently the engine is venting exhaust gases into the cooling system. Junkyard doesn't cover the cost of labor unless you buy their labor warranty. Not surprising really. I would have to swap the engine for another one of theirs to see if that works, or get a refund. After spending two weeks doing this job it's really starting to piss me off.

I'm considering having my old knocking engine rebuilt. I know its history and I've always taken excellent care of it, seems like a better way to go than getting another junkyard engine. Has anyone had a 2.4L rebuilt? If you did it yourself how much did it cost, and if you had it done how much? The engine is already out of the car and all accessories are stripped from it, so the cost of having someone do it would not include taking it out of the car, just the rebuild job. Thanks.

Just thought I'd come back and finish the thread up. I ended up getting another engine from the junkyard, put it in and no cooling problems. Nothing like buying a crap engine from a junkyard only to have to rip it back out and replace it again.