I plan on replacing the core sometime this summer, I'm worried that it may spring a leak at some point as well. Right now its not leaking and I've eliminated all other problems, the heat still works great, but something in that core is not right. I just put an amp in too a week ago, no coolant inside the cab at all. I'm just going to wait on the core until it warms up more outside since I don't have an inside garage to work on the thing and its freezing outside still. Right now she's sitting anyways while I wait for the gasket and hangers I needed to replace the muffler, found the muffler locally, but couldn't get the damn gasket locally to put it in, had to order it.

 

Hey,shimmy did you ever find out the prob. Would be nice to know because I'm having the same problems in my 94 3.0.

 

Bought a '91 Truck back in February and noticed the gurgle. I have since flushed the coolant, put in a new radiator (old one had a hole next to the cap), and t-stat. Prior to the radiator, coolant and t-stat the heat was hardly enough for me to drive without gloves in winter. Bled it a few times now and still have that same gurgle even after the new parts...

It's been cold here until last week and I noticed the gurgle was gone. Today was chilly again so I had the heat on and the gurgling is back.

I figured out that when my temperature control is set to cold the gurgle stops nearly immediately, when its set to hot it is pretty notable upon acceleration.

Any of you guys with this same pattern? Seems like that points toward some sort of issue with the heater core... Not sure if its worth fixing or looking at unless anyone has knowledge that this can lead to damage to the engine?

Thanks in advance for any input!

 

Uh you realize that the gurgling stops when temp set to cold because you are stopping the flow of coolant into the heater core. It's just air in your system, take it to a steep Hill and run with truck pointing up Hill. Turn off let cool, and add more coolant if necessary. May need to repeat. Very common on the 3vz

 

Yeah I did a fair share of poking around with this issue so I did the steep hill with it running a few times to try to solve it.

My main concern is if that air in the heater core can damage anything?

 

No damage but no heat. Whenever you do anything to the cooling system always make sure the heat is on hottest setting or the bubbles can't escape. I'd Park it on the hill and give it a good revving

 

Thanks for the input, RBX. Much appreciated.