C5 Z06 Oil Leak
Thread Starter
Heel & Toe
Joined: Dec 2014
Posts: 21
Likes: 0
From: Jacksonville FL
C5 Z06 Oil Leak
Before I have the intensive work to pull everything down from a possible rear main seal leak... I would like to get some feedback.
I did not have any visible oil leaks until I had my clutch replaced/upgraded to a C6 about a month or two ago. I noticed the leak on my garage floor right after the clutch change. Since then my tuner shop has added Kooks long tube headers and X pipe as well as a FAST 92 intake manifold. I have been trying to diagnose the source and determine if it had anything to do with the clutch replacement. The only oil seems to be coming from the housing behind the oil filter where the flywheel is located. I like my local tuner shop and do not want to accuse them of something that may just be a coincidence. Right now my car is sitting on a lift at my local repair shop that I also have a strong relationship with.
Please weigh in on this - thanks!
I did not have any visible oil leaks until I had my clutch replaced/upgraded to a C6 about a month or two ago. I noticed the leak on my garage floor right after the clutch change. Since then my tuner shop has added Kooks long tube headers and X pipe as well as a FAST 92 intake manifold. I have been trying to diagnose the source and determine if it had anything to do with the clutch replacement. The only oil seems to be coming from the housing behind the oil filter where the flywheel is located. I like my local tuner shop and do not want to accuse them of something that may just be a coincidence. Right now my car is sitting on a lift at my local repair shop that I also have a strong relationship with.
Please weigh in on this - thanks!
Pro
Joined: Jan 2010
Posts: 669
Likes: 13
Is your oil pressure reading right in the cluster?
Thread Starter
Heel & Toe
Joined: Dec 2014
Posts: 21
Likes: 0
From: Jacksonville FL
Oil pressure is reading properly but I am not opposed to proactively replacing it. You are VERY correct... just about anything else is going to be painful.
Advanced
Joined: Apr 2015
Posts: 84
Likes: 3
I was watching something on Velocity the other day and they had an ls1 with a leak there, after pulling the drivetrain apart, it was an oil plug on the back of the engine not rear main.
Did they change the pilot bearing/bushing when they did the clutch? I seem to recall if it's not installed CORRECTLY, there is an oil galley on the other side of the the bushing.
Did they change the pilot bearing/bushing when they did the clutch? I seem to recall if it's not installed CORRECTLY, there is an oil galley on the other side of the the bushing.
Tech Contributor
Joined: Dec 1999
Posts: 32,910
Likes: 2,402
From: Anthony TX
CI 6,7,8,9,11 Vet
St. Jude Donor '08
Obtain a nice bright light and use an inspection mirror and look at the area directly behind the intake manifold.
I've been there and you can observe the area and see if there is OIL coming from up high (CAM SENSOR, Oil PRESSURE SENSOR OR from a Knock sensor. Although when the knock senor floods with oil, you usually get a Knock sensor DTC)
If you are not sure and its very dirty back there, grab a can of brake parts cleaner and WASH DOWN the entire area and wipe all the oil and grime off the oil pan.
You can also look around the bell housing where it contacts the block and see if there is an oil trail there.
Don't forget to inspect the sensors, joints and gaskets around the oil filter housing and check the tightness of the upper oil pan bolts.
BC
I've been there and you can observe the area and see if there is OIL coming from up high (CAM SENSOR, Oil PRESSURE SENSOR OR from a Knock sensor. Although when the knock senor floods with oil, you usually get a Knock sensor DTC)
If you are not sure and its very dirty back there, grab a can of brake parts cleaner and WASH DOWN the entire area and wipe all the oil and grime off the oil pan.
You can also look around the bell housing where it contacts the block and see if there is an oil trail there.
Don't forget to inspect the sensors, joints and gaskets around the oil filter housing and check the tightness of the upper oil pan bolts.
BC
Thread Starter
Heel & Toe
Joined: Dec 2014
Posts: 21
Likes: 0
From: Jacksonville FL
I was watching something on Velocity the other day and they had an ls1 with a leak there, after pulling the drivetrain apart, it was an oil plug on the back of the engine not rear main.
Did they change the pilot bearing/bushing when they did the clutch? I seem to recall if it's not installed CORRECTLY, there is an oil galley on the other side of the the bushing.
Did they change the pilot bearing/bushing when they did the clutch? I seem to recall if it's not installed CORRECTLY, there is an oil galley on the other side of the the bushing.
Tech Contributor
Joined: Dec 1999
Posts: 32,910
Likes: 2,402
From: Anthony TX
CI 6,7,8,9,11 Vet
St. Jude Donor '08
Well,,,, If they didn't change the pilot brg,,, I would be PISSED. Mine only had 45K miles on it and it was in rough shape. It was dry and the needle bearings were ready to fall out. Yes, There is a WELSH PLUG that is pressed into the end of the crank that seals the pressurized crank oil from atmosphere.
If people are not careful when removing and installing a pilot bearing, it can get knocked out or punctured. You would really know if it was damaged. It gushes out!
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Pro
Joined: Jan 2010
Posts: 669
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Yes, There is a WELSH PLUG that is pressed into the end of the crank that seals the pressurized crank oil from atmosphere.
If people are not careful when removing and installing a pilot bearing, it can get knocked out or punctured. You would really know if it was damaged. It gushes out!
If people are not careful when removing and installing a pilot bearing, it can get knocked out or punctured. You would really know if it was damaged. It gushes out!
To the OP, if it's not the oil pressure sender, try to find a shop with a smoke machine for finding leaks. That's the best way I've ever used for finding difficult leaks.
Drifting
Joined: May 2007
Posts: 1,544
Likes: 209
From: Huntersville, NC
if the easy stuff is not leaking, then it might be the rear main crankshaft seal which is part of the rear engine cover. Some LS engines have a problem with casting porosity (sorta easy fix AFTER the flywheel is off), a little RTV on the pores is the cure.
see: http://www.cadillacforums.com/forums...b-05-06-a.html
If you can't find any other leak, then you might want to consider taking the clutch/flywheel back out and make sure oil hasn't gotten on the clutch, if the leak ends up being around the rear main or the rear cover. The joint between the rear engine cover gasket and the pan gasket got the clutch on my 07 CTS-V. Again a little dab of silicone there is good insurance.
see: http://www.cadillacforums.com/forums...b-05-06-a.html
If you can't find any other leak, then you might want to consider taking the clutch/flywheel back out and make sure oil hasn't gotten on the clutch, if the leak ends up being around the rear main or the rear cover. The joint between the rear engine cover gasket and the pan gasket got the clutch on my 07 CTS-V. Again a little dab of silicone there is good insurance.
Team Owner
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From: Dear Karma, I have a list of people you missed.
St. Jude Donor '08-'09-'10-'11-'12-'13-'14-'15-'16
Thread Starter
Heel & Toe
Joined: Dec 2014
Posts: 21
Likes: 0
From: Jacksonville FL
Yes, I did look at the invoice - it was not listed. I have left the shop a message explaining the situation (about needing to pull everything down and wanting to know if I need to proactively replace the bearing or if it was already done).