Compression check doesn't look good... Thoughts?
02-11-2017, 09:24 PM
#1
Instructor
Thread Starter
Compression check doesn't look good... Thoughts?
Engine let out a puff of white smoke at Sebring last weekend. I limped the car back to the pits sputtering and by the time I got the pits the car wouldn't stay started and sounded horrible.
Just got around to doing a quick compression check. There was no bad metal on metal sound so I know I didn't drop a valve or anything. No milky oil.
Here are the results:
Front
100______115
80_______110
80_______120
110______N/A
I couldn't free the rear right plug, and didn't want to risk breaking it. I will pull the heads anyways, cause of the 80's on the left side. While I am there I can check for ring problems.
What say you?
Just got around to doing a quick compression check. There was no bad metal on metal sound so I know I didn't drop a valve or anything. No milky oil.
Here are the results:
Front
100______115
80_______110
80_______120
110______N/A
I couldn't free the rear right plug, and didn't want to risk breaking it. I will pull the heads anyways, cause of the 80's on the left side. While I am there I can check for ring problems.
What say you?
Last edited by Boozshey; 02-11-2017 at 09:34 PM.
02-11-2017, 10:06 PM
#2
Safety Car
I cant Imagine all 8 cylinders suddenly going bad at once unless there was serious oil starvation (catastrophic oil pump failure).
Is it possible that the cam timing could have gotten off somehow? What kind of timing set do you have?
Is it possible that the cam timing could have gotten off somehow? What kind of timing set do you have?
02-11-2017, 10:24 PM
#4
Safety Car
It may have became un-adjusted. I wonder if you sheered that key,
If so I would be careful. Turning it over could hit the valves into the cylinders.
Damn, Seabring racway? Little envy.
If so I would be careful. Turning it over could hit the valves into the cylinders.
Damn, Seabring racway? Little envy.
Last edited by Rob 02; 02-11-2017 at 10:26 PM.
The following users liked this post:
Boozshey (02-11-2017)
02-11-2017, 10:34 PM
#6
Instructor
Thread Starter
I don't do any hard launches, but the car sees a lot of high revs. I wouldn't imagine a key breaking.
I am not sure how these adjust. But I had just came out of a turn and was from about 1/4 throttle to full throttle at about 50mph, then the engine fell over on itself. Later talking with the driver who was behind me, he mentioned the white smoke, which I then witnessed when I attempted to start the car to drive it into the trailer.
O'well, guess when we pull the heads we can take a look. Was just looking for opinions and other's ideas.
I am not sure how these adjust. But I had just came out of a turn and was from about 1/4 throttle to full throttle at about 50mph, then the engine fell over on itself. Later talking with the driver who was behind me, he mentioned the white smoke, which I then witnessed when I attempted to start the car to drive it into the trailer.
O'well, guess when we pull the heads we can take a look. Was just looking for opinions and other's ideas.
02-11-2017, 11:56 PM
#7
Safety Car
There's a 50% difference in cylinders. I would think that they would be more equal with retarded cam timing unless valves got bent. Maybe you blew both head gaskets at once (bolt stretch).
Some codes might tell a story.
Some codes might tell a story.
02-13-2017, 01:07 PM
#10
Instructor
Thread Starter
dropped the car off at the shop yesterday. Pulling heads regardless.
After looking through receipts I am not sure the shop that install the TEA heads used new bolts or not, I can't find a charge for them...
Well new APR studs are going in now anyways...
After looking through receipts I am not sure the shop that install the TEA heads used new bolts or not, I can't find a charge for them...
Well new APR studs are going in now anyways...
02-15-2017, 08:38 PM
#11
Instructor
Thread Starter
got the heads off and discovered the head gaskets were not installed as the manufacture intended. Notice the FRONT is at the back of the block.
Are the head gaskets directional. I come from a Ford mod motor back ground and this isn't even possible to accomplish.
Does this matter on an LS?
Are the head gaskets directional. I come from a Ford mod motor back ground and this isn't even possible to accomplish.
Does this matter on an LS?
02-16-2017, 05:27 PM
#17
Instructor
Thread Starter
Yes, looks like a re-sleeve would be needed.
And car was running so strong before all this...
And car was running so strong before all this...
Last edited by Boozshey; 02-16-2017 at 05:28 PM.
02-16-2017, 05:45 PM
#19
Instructor
Thread Starter
At this point no idea. Coming from the Ford world to the Chevy world there is a **** ton to learn about all the LSx...
Tonight after I mess with the new tire machines I plan to read up a bunch more on what's what.
the motor was putting out about 418rwhp/435tq and the way it was set up, I trusted the hell out of the car. I don't want to get too much power where it completely changes the characteristics of the cars handling.
Though it's not possible now of course, I just want that damn motor back... The car always ran amazing, until this day.
Tonight after I mess with the new tire machines I plan to read up a bunch more on what's what.
the motor was putting out about 418rwhp/435tq and the way it was set up, I trusted the hell out of the car. I don't want to get too much power where it completely changes the characteristics of the cars handling.
Though it's not possible now of course, I just want that damn motor back...
The car always ran amazing, until this day.
02-16-2017, 06:13 PM
#20
Safety Car
I think you can bore it .020" but a re-sleeve is not a simple task on these. I would be looking for another block if you cant over-boar it. My '02 LS1 block is the same as the LS6 so I'm assuming the '01-04 LS1 and 6 blocks are the same if that helps. Doing the LS3 update may be a good option.