06 OBXT Overheating/Gurgling

[Spoolin06XT]

Need some suggestions guys. I picked up this outback 2 years ago with 134K and it ran great. Not knowing if the TB was ever done I got that done at my local Subaru specialty shop as I didn't have the time. All OE parts including T-stat.

 

This year I started hearing air in the heater core. One summer day at lunch with the car running it started to over heat. So I stopped my lunch early, turned the heat on full blast and went back to work. With the ac it only went slightly over half way. I was able to put a funnel on it and try to bleed it but coolant kept pushing up thru the funnel and spilling over so I figured, great HG!

 

Since then I yanked the motor changed every coolant and vacuum hose and replaced the HG and used a set of ARP head studs. I even flushed out the heater core with a garden hose. Ok so I have only been using water since the OEM coolant is so damn expensive. Put water using the funnel and thought I got all the air out. Drove the car about 25 miles back to my house and get home shut the car off, and there it is again, gurgling.

 

Today I drove the car to work to see how bad the gurgling might get. Then was about a 20 mile trip to work, drives fine and no overheating, but gurgling at work. Ok, so I take it to lunch again, ate in my car with ac and again it starts to overheat. Again windows down, heat on full blast and head back to work. Arrived at work and gurgling is louder. Is this a block issue, small crack maybe?? I'm at a loss now because I don't know what else to check:mad:.

 

Note** I took the heads to the machine shop to skimmed and had 4 valves replaced that were bad. Blocked I cleaned off with the green abrasive pad.

 

Has anyone ran to this issue before? What did you do to fix it? Should I change the short block? You guys have any suggestions that could help?

 

TIA, Rod

[silverton]

Coolant pushing out of your funnel makes me think the thermostat isn't opening. Idle it in your driveway and wait for your fans to turn on. that indicates the thermostat should have opened and the lower radiator hose will get hot to the touch, if it stays cool the thermostat is stuck closed.

[Spoolin06XT]

Timing belt, seals, waterpump and thermostat were performed less than a year. Everything was replaced with OE parts. The bottom hose does get hot. I assume a cracked block as I vacuum tested the cooling system yesterday and it’s not holding vacuum.

[silverton]

New doesn't always mean good, I've had many new parts fail. But with the lower hose getting hot the thermostat is opening. If you're running straight water, and there is a leak somewhere, the gurgling you are hearing is likely the water boiling. Without being able to pressurize the boiling point is pretty close to the operating temperature of the motor.

 

Where are you bleeding the coolant from? The radiator itself, or the upper reservoir? You should be doing it from the upper reservoir.

 

Are you positive your vacuum tester has a good fit? Also positive that there are zero external leaks? How long does it take for the tester to drop vacuum?

[DaveWaters]

The gurgling you’re hearing may not be a symptom of the overheating. It may just be the blend door actuators on their way out. Mine’s been doing that for years.

 

When the engine starts to overheat have you checked to see if both the fans are on? Nothing impeding air flow through the core? Overheating while idling makes me think fans, blocked core, or tstat. You may want to get some coolant in there just so you might smell it if it’s leaking somewhere. And like said in an earlier post always bleed from the expansion tank by the turbo.