Looks like the same problem as the bad cams had from Comp Cam..
Damaged G5x3 cam... has lobe damage
Thread Starter
Melting Slicks
Joined: Feb 2002
Posts: 2,285
Likes: 2
From: Crooks SD
Damaged G5x3 cam... has lobe damage
I had to pull apart my built LS1 due to a faulty ring problem and much to my surprise, I found a damaged lobe on my LG G5x3 cam. The lifters have absolutely no marks indicating they were the problem. This cam was bought new from LG and doesn't have many miles. I have the receipt from the previous owner (dated 10-16-06).
Has anyone had this type of issue (with any cam, regardless of manufacturer/vender?)
I have not contacted LG yet.
edit: very large pictures attached.
Has anyone had this type of issue (with any cam, regardless of manufacturer/vender?)
I have not contacted LG yet.
edit: very large pictures attached.
Last edited by Jesse_Boyer; May 22, 2009 at 05:04 PM.
Thread Starter
Melting Slicks
Joined: Feb 2002
Posts: 2,285
Likes: 2
From: Crooks SD
it's a very mild 'marring' of the lobe surface. I'll try to snap a picture tonight.
Truth be told, I'm not even certain it's the rings. The motor was using about a quart of oil per 200 miles (if not more). I have little oily spots covering the rear fascia, and it bellows smoke on a hard acceleration as well as when I shift. I've only driven it about 500 miles since buying last year. (Had to replace a pilot bearing last fall, then it was winter before I knew it. Since I decided to pull the motor early April, it's been on jack stands more than it's been on the wheels!) Regardless, I did a compression test and all cylinders came back around 175psi or so, accept for the one odd-ball at 200-ish (numbers from memory, don't have the sheet in front of me). Then, after adding a dab of oil and running the tests again, I found the numbers jumped to around 220-psi on all cylinders. My research told me it was the rings at that point...
Truth be told, I'm not even certain it's the rings. The motor was using about a quart of oil per 200 miles (if not more). I have little oily spots covering the rear fascia, and it bellows smoke on a hard acceleration as well as when I shift. I've only driven it about 500 miles since buying last year. (Had to replace a pilot bearing last fall, then it was winter before I knew it. Since I decided to pull the motor early April, it's been on jack stands more than it's been on the wheels!) Regardless, I did a compression test and all cylinders came back around 175psi or so, accept for the one odd-ball at 200-ish (numbers from memory, don't have the sheet in front of me). Then, after adding a dab of oil and running the tests again, I found the numbers jumped to around 220-psi on all cylinders. My research told me it was the rings at that point...
Drifting
Joined: Dec 2005
Posts: 1,720
Likes: 3
From: East Hampton CT
Jesse, if you haven't put many miles on that car, its possible that your knockout plug on your crank was damaged when the pilot bearing was replaced! Many people don't know about the hollow crank on the LS1 and use the old method of cramming grease or wet toilet paper into the hole and then using a dowel to press out the bearing. Using that method will distort or break the knock out plug on the crank and then you'd be spitting oil out the back of your motor!
If that's not the issue, you might have a plugged or manfunctioning PCV system which would dump a lot of oil into the combustion chamber under hard acceleration.
I can't remember my PSI on my 1997 but I think it was in the 175 range too with 120,000 mi on the rings and new LS6 heads. That motor put down 412/396 to the wheels with the ported LS6 heads and G5X1 style custom cam so I think the bottom end is fine.
If that's not the issue, you might have a plugged or manfunctioning PCV system which would dump a lot of oil into the combustion chamber under hard acceleration.
I can't remember my PSI on my 1997 but I think it was in the 175 range too with 120,000 mi on the rings and new LS6 heads. That motor put down 412/396 to the wheels with the ported LS6 heads and G5X1 style custom cam so I think the bottom end is fine.
Tech Contributor
Joined: Jan 2007
Posts: 19,493
Likes: 1,178
From: Dyer, IN
I had to pull apart my built LS1 due to a faulty ring problem and much to my surprise, I found a damaged lobe on my LG G5x3 cam. The lifters have absolutely no marks indicating they were the problem. This cam was bought new from LG and doesn't have many miles. I have the receipt from the previous owner (dated 10-16-06).
Has anyone had this type of issue (with any cam, regardless of manufacturer/vender?)
I have not contacted LG yet.
Has anyone had this type of issue (with any cam, regardless of manufacturer/vender?)
I have not contacted LG yet.
Thread Starter
Melting Slicks
Joined: Feb 2002
Posts: 2,285
Likes: 2
From: Crooks SD
Jesse, if you haven't put many miles on that car, its possible that your knockout plug on your crank was damaged when the pilot bearing was replaced! Many people don't know about the hollow crank on the LS1 and use the old method of cramming grease or wet toilet paper into the hole and then using a dowel to press out the bearing. Using that method will distort or break the knock out plug on the crank and then you'd be spitting oil out the back of your motor!
If that's not the issue, you might have a plugged or manfunctioning PCV system which would dump a lot of oil into the combustion chamber under hard acceleration.
I can't remember my PSI on my 1997 but I think it was in the 175 range too with 120,000 mi on the rings and new LS6 heads. That motor put down 412/396 to the wheels with the ported LS6 heads and G5X1 style custom cam so I think the bottom end is fine.
If that's not the issue, you might have a plugged or manfunctioning PCV system which would dump a lot of oil into the combustion chamber under hard acceleration.
I can't remember my PSI on my 1997 but I think it was in the 175 range too with 120,000 mi on the rings and new LS6 heads. That motor put down 412/396 to the wheels with the ported LS6 heads and G5X1 style custom cam so I think the bottom end is fine.
If the knock out plug has been compromised, this wouldn't cause the motor to use oil during combustion. Rather, this would cause an oil leak, correct?
Regardless of whom build the motor, how does anyone know if it's ever the manufacturer or the installer/builders fault? Just a thought...
Le Mans Master
Joined: Feb 2002
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From: San Marcos Texas
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Thread Starter
Melting Slicks
Joined: Feb 2002
Posts: 2,285
Likes: 2
From: Crooks SD
Le Mans Master
Joined: Feb 2002
Posts: 5,970
Likes: 20
From: San Marcos Texas
Le Mans Master
Joined: Sep 2003
Posts: 6,276
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From: Farmington CT
Cruise-In VII Veteran
not the end, but also between the lobes
to the above poster, I think the cam journals are fine, looks like dust/lint to me
Last edited by SteveDoten; May 23, 2009 at 01:12 PM.
Tech Contributor
Joined: May 2008
Posts: 2,843
Likes: 16
From: Howell Michigan
St. Jude Donor '09-'10-'11
Just seen your photos. Yep, pretty bad. If you haven't already checked, look over the carrier for the lifter of the bad lobe. I have seen where they allow the lifter to rotate to the point where the roller skids instead of tracking true to rotation. If you don't find this to be the cause, then most likely the heat treat of the lobes was improper. I hope LG or who supplied the cam will stand behind it for you.
I agree with Steve, the cam bearing surface looks fine to me.
Keep us posted on how things go.
I agree with Steve, the cam bearing surface looks fine to me.
Keep us posted on how things go.
Le Mans Master
Joined: Sep 2003
Posts: 6,276
Likes: 227
From: Farmington CT
Cruise-In VII Veteran
the twisted lifter..............but sure have read it a lot on the forum
anyone have pics of that????
Pro
Joined: May 2004
Posts: 503
Likes: 1
From: WC MO
I was recently looking at buying a cam that looked like this. I called LG and was told that comp cams is the company to talk with and see if it could be regrinded. I called comp cams, and they asked if I bought the cam through them and I told them no, that I was looking to repair a cam. In short the answer was that they would no fix the cam since it was not purchased through comp cams. I called LG back and they said if comp made that statement then there was nothing they could do for a repair. This story could be different for you since you've pruchased the cam from LG. Good luck
Burning Brakes
Joined: Nov 2006
Posts: 1,071
Likes: 0
From: Goose Creek SC
I was recently looking at buying a cam that looked like this. I called LG and was told that comp cams is the company to talk with and see if it could be regrinded. I called comp cams, and they asked if I bought the cam through them and I told them no, that I was looking to repair a cam. In short the answer was that they would no fix the cam since it was not purchased through comp cams. I called LG back and they said if comp made that statement then there was nothing they could do for a repair. This story could be different for you since you've pruchased the cam from LG. Good luck
Race Director
Joined: Sep 2005
Posts: 11,060
Likes: 291
From: Pasco WA
