Oil in cylinder 7... where from?
Thread Starter
Senior Member
Joined: Aug 2014
Posts: 271
Likes: 39
From: SATX
'16 C63s
Oil in cylinder 7... where from?
Hi folks,
Did my spark plugs today (currently has 77k-ish miles, plugs last done at 60k) and noticed that the spark plug from cylinder 7 (second from firewall, driver's side) had a very noticeable amount of oil on the tip and threads; threads were practically covered in oil. With my borescope I was able to look in the cylinder and there was a little pool of oil at the bottom.
Doubt it's the piston rings, as there's no smoke from the exhaust. Also, all other cylinders / plugs looked fine. I don't have a compression tester so was not able to test, and had to button everything back up to get back on the road.
Anyone ever come across this on the M177? Any ideas? I'm guessing valve cover gasket? If so, who has done them and how much of a pain is it?
Car is a PFL.
Did my spark plugs today (currently has 77k-ish miles, plugs last done at 60k) and noticed that the spark plug from cylinder 7 (second from firewall, driver's side) had a very noticeable amount of oil on the tip and threads; threads were practically covered in oil. With my borescope I was able to look in the cylinder and there was a little pool of oil at the bottom.
Doubt it's the piston rings, as there's no smoke from the exhaust. Also, all other cylinders / plugs looked fine. I don't have a compression tester so was not able to test, and had to button everything back up to get back on the road.
Anyone ever come across this on the M177? Any ideas? I'm guessing valve cover gasket? If so, who has done them and how much of a pain is it?
Car is a PFL.
Member
Joined: Apr 2017
Posts: 185
Likes: 36
From: San Diego
C63S Coupe/CLA45
Hi folks,
Did my spark plugs today (currently has 77k-ish miles, plugs last done at 60k) and noticed that the spark plug from cylinder 7 (second from firewall, driver's side) had a very noticeable amount of oil on the tip and threads; threads were practically covered in oil. With my borescope I was able to look in the cylinder and there was a little pool of oil at the bottom.
Doubt it's the piston rings, as there's no smoke from the exhaust. Also, all other cylinders / plugs looked fine. I don't have a compression tester so was not able to test, and had to button everything back up to get back on the road.
Anyone ever come across this on the M177? Any ideas? I'm guessing valve cover gasket? If so, who has done them and how much of a pain is it?
Car is a PFL.
Did my spark plugs today (currently has 77k-ish miles, plugs last done at 60k) and noticed that the spark plug from cylinder 7 (second from firewall, driver's side) had a very noticeable amount of oil on the tip and threads; threads were practically covered in oil. With my borescope I was able to look in the cylinder and there was a little pool of oil at the bottom.
Doubt it's the piston rings, as there's no smoke from the exhaust. Also, all other cylinders / plugs looked fine. I don't have a compression tester so was not able to test, and had to button everything back up to get back on the road.
Anyone ever come across this on the M177? Any ideas? I'm guessing valve cover gasket? If so, who has done them and how much of a pain is it?
Car is a PFL.
Thread Starter
Senior Member
Joined: Aug 2014
Posts: 271
Likes: 39
From: SATX
'16 C63s
I'll have to order a compression tester, and no codes.
Junior Member
Joined: Apr 2021
Posts: 45
Likes: 6
2017 AMG C63s
I’m going to guess the oil was overfilled a little.
Thread Starter
Senior Member
Joined: Aug 2014
Posts: 271
Likes: 39
From: SATX
'16 C63s
Found it... found the stupid culprit: valve cover gasket. Turns out it was leaking right where it aligns with the cylinder 7.
I pulled the ignition coil today and was able to see it all - the tiny spot where the oil is coming out, leaking down into the spark plug shaft. The spark plug boot was moist with oil and there was some pooling of oil where the plug seats.
The oil i observed yesterday must've dripped down into the cylinder and top of the piston when I removed the plug.
On that note, anyone done valve cover gasket on our cars? How much of a PITA was it and, if taken to a shop, what was the damage $$ ?
I pulled the ignition coil today and was able to see it all - the tiny spot where the oil is coming out, leaking down into the spark plug shaft. The spark plug boot was moist with oil and there was some pooling of oil where the plug seats.
The oil i observed yesterday must've dripped down into the cylinder and top of the piston when I removed the plug.
On that note, anyone done valve cover gasket on our cars? How much of a PITA was it and, if taken to a shop, what was the damage $$ ?
Trending Topics
Junior Member
Joined: Apr 2021
Posts: 45
Likes: 6
2017 AMG C63s
Found it... found the stupid culprit: valve cover gasket. Turns out it was leaking right where it aligns with the cylinder 7.
I pulled the ignition coil today and was able to see it all - the tiny spot where the oil is coming out, leaking down into the spark plug shaft. The spark plug boot was moist with oil and there was some pooling of oil where the plug seats.
The oil i observed yesterday must've dripped down into the cylinder and top of the piston when I removed the plug.
On that note, anyone done valve cover gasket on our cars? How much of a PITA was it and, if taken to a shop, what was the damage $$ ?
I pulled the ignition coil today and was able to see it all - the tiny spot where the oil is coming out, leaking down into the spark plug shaft. The spark plug boot was moist with oil and there was some pooling of oil where the plug seats.
The oil i observed yesterday must've dripped down into the cylinder and top of the piston when I removed the plug.
On that note, anyone done valve cover gasket on our cars? How much of a PITA was it and, if taken to a shop, what was the damage $$ ?
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Thread Starter
Senior Member
Joined: Aug 2014
Posts: 271
Likes: 39
From: SATX
'16 C63s
I had this happen to my PFL C63 and it eventually dried 😖. I almost made sure to drain the oil completely and be careful when filling it. But it eventually dried and never had any more issues with the valve gasket leaking. I think it could be an extensive job (may have to pull the engine?)
Out Of Control!!
Joined: Sep 2018
Posts: 14,690
Likes: 4,584
From: unbegrenzt
2017 GLE350 4MATIC
MB engine covers and plates are generally adhered using adhesive. Careful cleaning away of the old sealant and avoiding damage of the machined mating surface is important. And use of the proper MB sealant with proper application quantity and location are important. Plus removal and disassembly of parts, probably breaking one or two heat-aged items in the process that need to be replaced.
If you are comfortable with all of that, it’s not hard. If it were me I would have an Indy do it.
If you are comfortable with all of that, it’s not hard. If it were me I would have an Indy do it.
Thread Starter
Senior Member
Joined: Aug 2014
Posts: 271
Likes: 39
From: SATX
'16 C63s
MB engine covers and plates are generally adhered using adhesive. Careful cleaning away of the old sealant and avoiding damage of the machined mating surface is important. And use of the proper MB sealant with proper application quantity and location are important. Plus removal and disassembly of parts, probably breaking one or two heat-aged items in the process that need to be replaced.
If you are comfortable with all of that, it’s not hard. If it were me I would have an Indy do it.
If you are comfortable with all of that, it’s not hard. If it were me I would have an Indy do it.
