Hey guys I've got a pretty confusing situation. I typically am pretty decent at troubleshooting engine issues, but this one has me stumped.
Let me give you the background, ej253 from a 2006 impreza 2.5I, purchased on craigslist from a wrecked car with 65k miles. Did a timing belt/waterpump and swapped the appropriate sensors to drop it into my forester.
Started the engine, had a smoking issue from the get go. The smoking wasn't TOO bad though, and I had put oil in the cylinders and turned them by hand to lube them up before starting it, so that was expected. Seemed like it was burning coolant too, so suspected a headgasket.
After about 20 mins of runtime, still smoking steadily, the motor let loose. It just started burning oil worse than I've ever seen, HUGE smoke cloud - i shut it off immediately. Not sure anymore if there was coolant burning too, or just oil - the smell and color was predominantly oil.. stink and blue.
Now, this is where things get confusion. I assumed a good ole leakdown test would find my culprit.
Cylinders 1-4 ALL were within 5% of each other, and ALL read good (under 15% leak) on my tester running @40psi or so.
This confused me, so i turned to a compression test.
Passanger side was in the 140's compression on both, within 5psi of each other.
Drivers side was in the 160's compression on both, again within 5psi of each other.
I've never seen a engine where the compression test shows different from the leakdown test.
Now, I know i need to tear this thing down and look into it now, but i wanted to see what the subie community has to say on this one. It's a real bummer and I was hoping it was a headgasket at first, but considering its oil that is burning and the rate it is consuming it, I'm just not sure.
Ringlands are a common issue, but those should have been OBVIOUS with the leakdown test and not given me good results.
Oil control ring? valve stem seals? Not sure what else could cause this.
To give you an idea, it burned probably almost 2 quarts within 20 mins of running total. Honestly, i think now it's consuming more like a quart / 5 minutes at this point. It's bad.
Any ideas guys? Like i said I know it's teardown time, I just would like to know what to look for.
Thanks much.
Let me give you the background, ej253 from a 2006 impreza 2.5I, purchased on craigslist from a wrecked car with 65k miles. Did a timing belt/waterpump and swapped the appropriate sensors to drop it into my forester.
Started the engine, had a smoking issue from the get go. The smoking wasn't TOO bad though, and I had put oil in the cylinders and turned them by hand to lube them up before starting it, so that was expected. Seemed like it was burning coolant too, so suspected a headgasket.
After about 20 mins of runtime, still smoking steadily, the motor let loose. It just started burning oil worse than I've ever seen, HUGE smoke cloud - i shut it off immediately. Not sure anymore if there was coolant burning too, or just oil - the smell and color was predominantly oil.. stink and blue.
Now, this is where things get confusion. I assumed a good ole leakdown test would find my culprit.
Cylinders 1-4 ALL were within 5% of each other, and ALL read good (under 15% leak) on my tester running @40psi or so.
This confused me, so i turned to a compression test.
Passanger side was in the 140's compression on both, within 5psi of each other.
Drivers side was in the 160's compression on both, again within 5psi of each other.
I've never seen a engine where the compression test shows different from the leakdown test.
Now, I know i need to tear this thing down and look into it now, but i wanted to see what the subie community has to say on this one. It's a real bummer and I was hoping it was a headgasket at first, but considering its oil that is burning and the rate it is consuming it, I'm just not sure.
Ringlands are a common issue, but those should have been OBVIOUS with the leakdown test and not given me good results.
Oil control ring? valve stem seals? Not sure what else could cause this.
To give you an idea, it burned probably almost 2 quarts within 20 mins of running total. Honestly, i think now it's consuming more like a quart / 5 minutes at this point. It's bad.
Any ideas guys? Like i said I know it's teardown time, I just would like to know what to look for.
Thanks much.