Oops
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From: Racine, Wisconsin
LM7 with over 280K miles, Z06 cam with stock everything else (including original springs)
flipped 2010 manifolds
HX55
Truck intake
Siemens 80#
Walbro 450
two Tial 38's with lightest spring (4.8 psi boost)
boost ref magnafuel regulator base = 43 psi
flipped 2010 manifolds
HX55
Truck intake
Siemens 80#
Walbro 450
two Tial 38's with lightest spring (4.8 psi boost)
boost ref magnafuel regulator base = 43 psi
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Thread Starter
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From: Racine, Wisconsin
Went for a drive Friday evening... A few dozen 0-60 pulls @ 5 psi data logging ... nothing special, drove home, parked in the garage...
Next morning started it and it immediately started smoking... A lot ... No rattle or anything special... After about 30 seconds it started missing on one cylinder...
Lifted hood and found it spraying oil out of the drives side manifold...
Found plug 5 covered in oil, but all 4 drivers side cylinders have decent compression 135 - 150
#5 was the best...
I expected one low cylinder and a damaged plug, but the other plugs all looked fine, a fairly rich, but no damage.
Next morning started it and it immediately started smoking... A lot ... No rattle or anything special... After about 30 seconds it started missing on one cylinder...
Lifted hood and found it spraying oil out of the drives side manifold...
Found plug 5 covered in oil, but all 4 drivers side cylinders have decent compression 135 - 150
#5 was the best...
I expected one low cylinder and a damaged plug, but the other plugs all looked fine, a fairly rich, but no damage.
Last edited by twinturbo496; Dec 7, 2015 at 10:04 PM.
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From: Racine, Wisconsin
Pulled the head expecting a broken piston....
After spraying a little carb cleaner and wiping it off with a paper towel I found this in all four holes on the drivers side...
After spraying a little carb cleaner and wiping it off with a paper towel I found this in all four holes on the drivers side...
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From: Racine, Wisconsin
I have no idea what happened. The intake had a little bit of oil inside, but not enough to make the engine into a mosquito killer.....
The passenger side intake, exhaust & that side of the divided turbo are completely dry.
If that piston is broken underneath without any damage to the top or the cylinder walls it will be the first time I have ever seen anything like it...
Where the hell did all the oil come from? It was slobbering all over the drivers side. The video is after I sprayed it off the first time and ran it again for just a few seconds...
What next? Pull the pan & remove # 5 is my next step, or just put in new MLS gaskets & some ARP bolts and run it again???
The passenger side intake, exhaust & that side of the divided turbo are completely dry.
If that piston is broken underneath without any damage to the top or the cylinder walls it will be the first time I have ever seen anything like it...
Where the hell did all the oil come from? It was slobbering all over the drivers side. The video is after I sprayed it off the first time and ran it again for just a few seconds...
What next? Pull the pan & remove # 5 is my next step, or just put in new MLS gaskets & some ARP bolts and run it again???
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Can you wipe the ciylinder down a bit better? & take a pic?
Did you do a leak down before you took it apart?
Broken rings?
Valve seals?
If the exhaust is clean that would tend to eliminate the rear turbo seal. In the intake would lead me to believe the seal behind the compressor housing.
Only so many places to get oil in there from.
Did you do a leak down before you took it apart?
Broken rings?
Valve seals?
If the exhaust is clean that would tend to eliminate the rear turbo seal. In the intake would lead me to believe the seal behind the compressor housing.
Only so many places to get oil in there from.
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From: Racine, Wisconsin
I am out of town for work this week.
The bores don't look great, but the mileage is probably actually over 300K now, so i suppose I can't complain. The cross hatch is still barely visible, I was surprised that they don't have any ridge at all.
I don't have a leak down tester, but maybe I will get one and check the passenger side before I pull the pan off.
I can't believe that running a pcv valve in the stock location could push that much oil up into the intake after only maybe 5 minutes running at 5 psi boost... but maybe I am wrong on that... Perhaps going on/off boost 2 dozen times pushes more oil up?
The bores don't look great, but the mileage is probably actually over 300K now, so i suppose I can't complain. The cross hatch is still barely visible, I was surprised that they don't have any ridge at all.
I don't have a leak down tester, but maybe I will get one and check the passenger side before I pull the pan off.
I can't believe that running a pcv valve in the stock location could push that much oil up into the intake after only maybe 5 minutes running at 5 psi boost... but maybe I am wrong on that... Perhaps going on/off boost 2 dozen times pushes more oil up?
