Excessive Blow By
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Excessive Blow By
Well, I believe I hurt my engine (6.0L / MP T-76) the other day. I was trying to dial in my tune @ about 12 psi on the street but couldn't get my AFRs correct. When I got back to my house I notice that I have lots of smoke coming out of the valve covers and dipstick tube. The engine seems to be running ok other than a slight miss.
I searched for PCV valves on these engines and as far as I can tell the engine just vents through valve covers correct? My guess is I have hurt a piston or at least the rings. Since it may already be toast but seems to running okay should I keep going or tear it down? I think I know the answer but figured I would post to see if anybody else has run into this problem. Thanks!
I searched for PCV valves on these engines and as far as I can tell the engine just vents through valve covers correct? My guess is I have hurt a piston or at least the rings. Since it may already be toast but seems to running okay should I keep going or tear it down? I think I know the answer but figured I would post to see if anybody else has run into this problem. Thanks!
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alot of people use a catch can when uping the boost on ls engines. im not very experience with that subject as far as how everything is ran, but i know its a problem.
dont be so quick to assume your engine is toast though
dont be so quick to assume your engine is toast though
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I need to remind myself in these situations to KISS. If you have run the car on boost for some time without this problem then I would guess the increased boost is pulling more oil into the motor and a catch can setup is a good move. I have heard guys who have taken out pistons will have the dip stick blow out part way. If it doesn't clear up, do a leak down test. Do you have the vent hose to the side of the throttle body blocked off?
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I third the motion of a compression/leakdown test, this will tell you if the motor is ok. If its good, there is a sponsor on here, Lashway Motorsports, that make a catch can built for boost with built in check valves. setup properly, it will pull vaccum on the crankcase all the way through the rpm range, regardless of what the induction side is doing. good insurance
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So I plan on doing a compression test to confirm my suspicions. Do y'all think if all I did was damage the ring land I will be able to get by with a cylinder hone? I don't want go through getting the entire block machined and all that comes with that. If I can get by with a fresh set of forged pistons and rods that should be plenty for my goals. I'm just trying to build something that will hold about 15-18 psi of boost and still be fun to drive.
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So I plan on doing a compression test to confirm my suspicions. Do y'all think if all I did was damage the ring land I will be able to get by with a cylinder hone? I don't want go through getting the entire block machined and all that comes with that. If I can get by with a fresh set of forged pistons and rods that should be plenty for my goals. I'm just trying to build something that will hold about 15-18 psi of boost and still be fun to drive.
#13
So I plan on doing a compression test to confirm my suspicions. Do y'all think if all I did was damage the ring land I will be able to get by with a cylinder hone? I don't want go through getting the entire block machined and all that comes with that. If I can get by with a fresh set of forged pistons and rods that should be plenty for my goals. I'm just trying to build something that will hold about 15-18 psi of boost and still be fun to drive.