Cause of Overheating?
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Car Info: 05 LGT Wagon 5spd, '11 R6 Race
Cause of Overheating?
I have a 2003 OBS.
Previous problem- I was running a rebuilt 98 ej25D block with thick headgaskets and 2003 SOHC heads and all sohc wiring exhaust, basically everything else. However, that engine kept overheating, so we assumed that the headgaskets were not thick enough (compression too high, causing engine to overheat).
I gave up with that setup, just swapped in an ej251 with 80k miles on it, used the 2003 intake manifold and everything etc.
took it for a quick test drive today, the coolant started to back up and I could hear it bubbling in the top radiator hose. The overflow tank had more coolant than I put in it when I filled the radiator.
Also, the car has a brand new coolant temp sensor. The thermostat looked pretty good, I have a new one i could put in if neccesary, but i dont think thats the cause
another thing to note -
I changed the oil/filter last night, there was no coolant in the oil so im confident its not blown HGs's
Could it be possible that the radiator is bad? The problem keeps happening and this is a completely different engine
Previous problem- I was running a rebuilt 98 ej25D block with thick headgaskets and 2003 SOHC heads and all sohc wiring exhaust, basically everything else. However, that engine kept overheating, so we assumed that the headgaskets were not thick enough (compression too high, causing engine to overheat).
I gave up with that setup, just swapped in an ej251 with 80k miles on it, used the 2003 intake manifold and everything etc.
took it for a quick test drive today, the coolant started to back up and I could hear it bubbling in the top radiator hose. The overflow tank had more coolant than I put in it when I filled the radiator.
Also, the car has a brand new coolant temp sensor. The thermostat looked pretty good, I have a new one i could put in if neccesary, but i dont think thats the cause
another thing to note -
I changed the oil/filter last night, there was no coolant in the oil so im confident its not blown HGs's
Could it be possible that the radiator is bad? The problem keeps happening and this is a completely different engine
over the last few years I've noticed that Paul has ninja skills for diagnosing problems...whenever somebody posts a problem he normally gets it right with just a few questions....
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Car Info: 05 LGT Wagon 5spd, '11 R6 Race
absolutely no leaks that ive been able to find. Ive left the car in the garage over night and there was nothing under the car
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I'll replace the thermo and see what happens. thats easy enough
I definitely bled the system completely. that was one of the first things I tried
I definitely bled the system completely. that was one of the first things I tried
Blown Head gasket does not mean there's gonna be water in the oil. Cylinder pressure makes its way into the water jacket displaces the water through the overflow. Eventually no cooling. Seen in on a few separate occasions.
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I burped/bled it properly I believe. It looked like all the air was out and there was no more coolant that could go in.
^ this might be true, and i rather it wasnt the case lol. But we'll see.
I called two subaru shops around (Fine Line/PJ's foreign Auto) that ive been talking to a ton and they think its possible that it could be the radiator. I pulled it out this morning and brought it to a good radiator shop suggested by Pj's for a flow test. They checked it out and they said they think its the cause of the overheating, it doesnt have good flow or whatever. They are going to clear it out/fix it and then ill throw it back in the car tomorrow and see what happens.
I called two subaru shops around (Fine Line/PJ's foreign Auto) that ive been talking to a ton and they think its possible that it could be the radiator. I pulled it out this morning and brought it to a good radiator shop suggested by Pj's for a flow test. They checked it out and they said they think its the cause of the overheating, it doesnt have good flow or whatever. They are going to clear it out/fix it and then ill throw it back in the car tomorrow and see what happens.
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Car Info: 2005 LGT wagon
You may still need to repair the head gaskets after the radiator returns.