Anthony Boni
5+ Year Contributor
- 213
- 23
- May 13, 2018
-
Wrightstown,
New_Jersey
Hello. I’ll get straight to the point. This is going to be a bit of a longer post! I have one black spark plug on cylinder two, and I’m burning oil at WOT. Here is what I have diagnosed:
Recently built 6 bolt motor. 2.3 stroker, your average wiseco piston/eagle rod combo. Roughly 1,000 miles on the build now. Compression test all 4, 185-190 all across. Leak down is great on each cylinder as well. I don’t have a number of actual leakage I can post because the second gauge on my leakdown tester does not work. If I had to put a number on the amount of leakage, I’d hypothesize less than 5% on each cylinder. I can hardly hear any air at all coming from the oil filler cap. I have to really listen to hear it. No air escaping the intake/exhaust valves, no air pressurizing the coolant system, no air escaping another cylinder.
Leakdown and compression tests are good. So I removed the exhaust manifold to inspect the valve stem seals for leakage. I’ve attach pictures so you can view them as well. #1 looks completely dry, 2-4 looks a LITTLE damp around the valve guide tips. It doesn’t look like valve stem seals I’ve seen leak in the past. On the exhaust manifold flange and on the head where the exhaust manifold meets, there was unburnt oil. I’ve attached a picture of that as well.
Next, I removed the intake from my turbo. There was one drip of oil in the compressor housing. No shaft play.
I currently have a dual 10AN oil cap going to a sealed catch can with a single 10AN out to to pre turbo on the intake.
So I didn’t find much in the way of why I’m burning oil at WOT, or where it’s coming from. What else should I be looking into? #2’s plug is substantially darker than the other 3 cylinders. It does not look like oil though, it looks like it’s running rich. I am going to get a borescope to inspect my intake valves for oil, because that’s the only thing I can think of. Thanks.
Recently built 6 bolt motor. 2.3 stroker, your average wiseco piston/eagle rod combo. Roughly 1,000 miles on the build now. Compression test all 4, 185-190 all across. Leak down is great on each cylinder as well. I don’t have a number of actual leakage I can post because the second gauge on my leakdown tester does not work. If I had to put a number on the amount of leakage, I’d hypothesize less than 5% on each cylinder. I can hardly hear any air at all coming from the oil filler cap. I have to really listen to hear it. No air escaping the intake/exhaust valves, no air pressurizing the coolant system, no air escaping another cylinder.
Leakdown and compression tests are good. So I removed the exhaust manifold to inspect the valve stem seals for leakage. I’ve attach pictures so you can view them as well. #1 looks completely dry, 2-4 looks a LITTLE damp around the valve guide tips. It doesn’t look like valve stem seals I’ve seen leak in the past. On the exhaust manifold flange and on the head where the exhaust manifold meets, there was unburnt oil. I’ve attached a picture of that as well.
Next, I removed the intake from my turbo. There was one drip of oil in the compressor housing. No shaft play.
I currently have a dual 10AN oil cap going to a sealed catch can with a single 10AN out to to pre turbo on the intake.
So I didn’t find much in the way of why I’m burning oil at WOT, or where it’s coming from. What else should I be looking into? #2’s plug is substantially darker than the other 3 cylinders. It does not look like oil though, it looks like it’s running rich. I am going to get a borescope to inspect my intake valves for oil, because that’s the only thing I can think of. Thanks.
Attachments
-
3DCBEC47-95C4-4769-A198-350EFCCB5454.jpg21.3 KB · Views: 109
-
AF593CCA-A1ED-49E7-96D0-A6CFFEFC20BE.jpg24.7 KB · Views: 99
-
C8496A3F-2EF1-4722-88EC-F433E0ABCB6B.jpg21.7 KB · Views: 89
-
F53ED1E3-564D-42AE-91F1-225A354CC9CC.jpg22.5 KB · Views: 97
-
D82A7D03-F72A-4568-989C-96D6BB8A0E94.jpeg44.6 KB · Views: 91
-
82ED071F-C14F-4816-AC1A-0C92F58A7568.jpeg45.8 KB · Views: 97