My DynoTune Went Horribly Wrong...
Thread Starter
Drifting
Joined: Apr 2007
Posts: 1,848
Likes: 1
From: Central Florida
My DynoTune Went Horribly Wrong...
After all this time building my motor it came down to today.. Off to ECS for my dynotune. 2003 z06, cam, headers, cai, new rods, pistons, rings, bearings etc, etc. Barely pushed 350 rwhp.. I don't know WTF is worng? To make matters worse, drove all the way back home with a engine knock and 15psi of Oil Pressure the entire ride home. Not to mention a big dent on my wallet..
I'm went back in and check the cam alignment, but it's dead on.. Removed the oil pump and oil ring seal is like new, it was never pinched or anything.. I guess only one thing left to do, A Leak Down..
I'm went back in and check the cam alignment, but it's dead on.. Removed the oil pump and oil ring seal is like new, it was never pinched or anything.. I guess only one thing left to do, A Leak Down..
Last edited by BonestockZ06; Nov 28, 2007 at 08:35 PM. Reason: adding
Thread Starter
Drifting
Joined: Apr 2007
Posts: 1,848
Likes: 1
From: Central Florida
I did the motor myself, it was just a simple rebuilt. I had the cylinders honed, but that was it. ECS tried their best to tune it but to no avail. Doug suggested Run a leak.
Last edited by BonestockZ06; Dec 3, 2007 at 02:08 PM.
Safety Car
Joined: Sep 2003
Posts: 3,558
Likes: 2
From: Cape Coral FL
New rods, pistons, rings, and bearings is more than a cylinder hone. As Doug suggested do a leakdown. I would also do a compression test. 15psi oil pressure could mean a pinched pickup to oil pump o-ring, or excessive main bearing clearance. Did you verify your clearances when installing the new bearings? What about rotating assembly balance? Di you check your rings for proper end gap?
---
I know I may be asking the obvious questions, but what you are describing sounds like some of these things were overlooked or not done to proper tolerances.
---
I know I may be asking the obvious questions, but what you are describing sounds like some of these things were overlooked or not done to proper tolerances.
Thread Starter
Drifting
Joined: Apr 2007
Posts: 1,848
Likes: 1
From: Central Florida
New rods, pistons, rings, and bearings is more than a cylinder hone. As Doug suggested do a leakdown. I would also do a compression test. 15psi oil pressure could mean a pinched pickup to oil pump o-ring, or excessive main bearing clearance. Did you verify your clearances when installing the new bearings? What about rotating assembly balance? Di you check your rings for proper end gap?
---
I know I may be asking the obvious questions, but what you are describing sounds like some of these things were overlooked or not done to proper tolerances.
---
I know I may be asking the obvious questions, but what you are describing sounds like some of these things were overlooked or not done to proper tolerances.
Cam is dead on.. Dot to Dot.. If what I just described is not proper, then I don't need to look any further because then we have found the problem/s.
Thanks
Le Mans Master
Joined: Aug 2001
Posts: 8,145
Likes: 1
From: Bradenton FLORIDA
I meant the only machining to the block was a cylinder hone... .003 on the bearings. Assembly is fully balanced. The oil pump ring wasn't pinched, however, I did find the relief valve stuck, but on the closed position, that should have given me more pressure, right? Gap is at 14 for the first ring and 17 for the second.
Cam is dead on.. Dot to Dot.. If what I just described is not proper, then I don't need to look any further because then we have found the problem/s.
Thanks
Cam is dead on.. Dot to Dot.. If what I just described is not proper, then I don't need to look any further because then we have found the problem/s.
Thanks
Don't always trust the dot's....degree it to see for sure. Also, .002-.0025 on the bearings unless it is an all out race motor.
Race Director
Joined: May 2005
Posts: 15,960
Likes: 21
From: West Norriton PA
St. Jude Donor '08
I meant the only machining to the block was a cylinder hone... .003 on the bearings. Assembly is fully balanced. The oil pump ring wasn't pinched, however, I did find the relief valve stuck, but on the closed position, that should have given me more pressure, right? Gap is at 14 for the first ring and 17 for the second.
Cam is dead on.. Dot to Dot.. If what I just described is not proper, then I don't need to look any further because then we have found the problem/s.
Thanks
Cam is dead on.. Dot to Dot.. If what I just described is not proper, then I don't need to look any further because then we have found the problem/s.
Thanks
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Thread Starter
Drifting
Joined: Apr 2007
Posts: 1,848
Likes: 1
From: Central Florida
It wasn't great, but it wasn't as bad as it became after the pulls... I was having issues with it, but only at idle. Now it will not raise pressure with higher rpms at all. Hard to tell where the knock is coming from, I'm hoping it was just valvetrain noise from the low oil pressure..
Safety Car
Joined: Sep 2003
Posts: 3,558
Likes: 2
From: Cape Coral FL
Doh! Sorry, I didn't absorb the symptom that you have a knock. With low oil pressure and a knock I have to agree you may have spun a bearing on the dyno. Also, +1 on degreeing the cam. you wouldn't be the first one I've read about with a bad grind.
Last edited by ArKay99; Nov 28, 2007 at 11:53 PM.
Pro
Joined: Feb 2007
Posts: 702
Likes: 1
From: Frankfort Il
All the spun cam bearings I've seen resulted in no oil pressure...It'd be odd that it would only spin a little bit, those oil passages are pretty small. Collapsed lifter maybe? or something blocking oil from pumping up a lifter, which would act like a dead hole, a leakdown/compression test can show you that, hell looking at the plugs will tell you if it's a dead hole.
Thread Starter
Drifting
Joined: Apr 2007
Posts: 1,848
Likes: 1
From: Central Florida
All the spun cam bearings I've seen resulted in no oil pressure...It'd be odd that it would only spin a little bit, those oil passages are pretty small. Collapsed lifter maybe? or something blocking oil from pumping up a lifter, which would act like a dead hole, a leakdown/compression test can show you that, hell looking at the plugs will tell you if it's a dead hole.
I originally though it was a pinched o-ringed and was on my to do list next. However, now the pressure will not raise past 14-15 psi at any given rpm ( I've gone as far as 3k rpms and it just will not raise. I drove home with some engine noise, but It's hard to describe, it almost felt like it was coming through the center vents.. I never got a warning light and the noise is only coming through under acceleration. Pull the codes and had none, I'd figure, maybe I'll get a knock sensor code, but no..
I came home pulled the front cover off and removed the oil pump. Oil ring was seated properly, looks brand new with no signs of being pinched anywhere. I opened the pump and the relieve valve was stuck closed, shouldn't that be more pressure instead of less. I mean, I had to pry it with a thin screw driver to get it lose. Is the valve supposed to move freely? Can it be a faulty Oil Pump?
Last, I checked the cam alignment and it's dead on dot to dot.. I will be running a leak down test later on tonight.
Last edited by BonestockZ06; Dec 3, 2007 at 02:10 PM.
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Damn Juan, you took that apart fast!!
You only left here mid day yesterday!
it's a shame the build did not go as planned, personally I would pull the motor and completely tear it down. A cam bearing could have walked and personally I think your bearing clearances are too loose anyway. At least it's winter time now and you can take your time and build it right.
You only left here mid day yesterday!
it's a shame the build did not go as planned, personally I would pull the motor and completely tear it down. A cam bearing could have walked and personally I think your bearing clearances are too loose anyway. At least it's winter time now and you can take your time and build it right.
Drifting
Joined: Oct 2004
Posts: 1,384
Likes: 8
From: Southwest Virginia
100%!!! Best advice here yet. An oil filter will tell you a lot about the engine if something when majority wrong in there. You shouldn't see much copper if any in a new build. But if you have turned a bearing you will most likely see the damage in the filter, no matter how bad the bearing turned.As far as low power, are you sure the pistons decked back to the top of the block? Did you check deck height after assembly? These motors normally run 0 to +.005 (piston slightly out of the hole). If you ended up with the wrong pistons or rods your piston height may be way below the deck causing an extremely low compression ratio. Do a compression check as well as a leak down to eliminate that possibility.
Did the engine run smooth or did it seem to have a miss before the dyno pulls?
Thread Starter
Drifting
Joined: Apr 2007
Posts: 1,848
Likes: 1
From: Central Florida
100%!!! Best advice here yet. An oil filter will tell you a lot about the engine if something when majority wrong in there. You shouldn't see much copper if any in a new build. But if you have turned a bearing you will most likely see the damage in the filter, no matter how bad the bearing turned.As far as low power, are you sure the pistons decked back to the top of the block? Did you check deck height after assembly? These motors normally run 0 to +.005 (piston slightly out of the hole). If you ended up with the wrong pistons or rods your piston height may be way below the deck causing an extremely low compression ratio. Do a compression check as well as a leak down to eliminate that possibility.
Did the engine run smooth or did it seem to have a miss before the dyno pulls?
amn Juan, you took that apart fast!!
You only left here mid day yesterday!
it's a shame the build did not go as planned, personally I would pull the motor and completely tear it down. A cam bearing could have walked and personally I think your bearing clearances are too loose anyway. At least it's winter time now and you can take your time and build it right.
You only left here mid day yesterday!
it's a shame the build did not go as planned, personally I would pull the motor and completely tear it down. A cam bearing could have walked and personally I think your bearing clearances are too loose anyway. At least it's winter time now and you can take your time and build it right.
Thread Starter
Drifting
Joined: Apr 2007
Posts: 1,848
Likes: 1
From: Central Florida
