See if you can figure this one out.
Thread Starter
Member
Joined: Jul 1999
Posts: 327
Likes: 0
From: Stillwater, Oklahoma, USA
See if you can figure this one out.
OK, a couple months ago I got in my car (88FormulaL98) to go home and it was missing really badly and when you put the motor under any kind of load whatsoever, it would knock, rattle, etc. Sounds just like spark knock. Have good oil pressure.
Well, thought it might be a valve spring broken, or lifter collapsed or something of that nature. Then it started using coolant and smoking white from the tail-pipe.
So, I change head gaskets. The gasket was blown in between cylinders 3 & 5. I figured the compression from 3 was leaking over into 5 and visa versa causing the detonation sounds.
Get this; The #5 piston was not sitting in the bore straight! It was twisted clock-wise in the bore (bent-rod, twisted rod,)! The piston was noticable just by looking at it. Put it all back together, still doing the same ****. Starting to make me mad.
I am trying to figure out the relationship between the #5 piston being rotated in the bore, the head gasket blown between #3 & #5, and that spark knock sound coming from the motor. Still have good oil pressure.
Any ideas???? Somebody please explain this.
------------------
L98, 3.27 9-bolt, Hooker shorty headers, custom 2.5inch Y-pipe, no cat, 3inch 2chamber flowmaster, JET AFPR, Ported MAF, Best ET: 13.86 @100mph. 1.99 60'
17 inch ROH "ZS" wheels. 17x8.5(front) and 17x9.5 (rear). Firestone Firehawk SZ50s. 245/45/zr17s and 275/40/zr17s. T56
On the way... Radar Blue 89 Formula, T56, Ram Jet 430, Ram Air, 17inch ROHs.
Well, thought it might be a valve spring broken, or lifter collapsed or something of that nature. Then it started using coolant and smoking white from the tail-pipe.
So, I change head gaskets. The gasket was blown in between cylinders 3 & 5. I figured the compression from 3 was leaking over into 5 and visa versa causing the detonation sounds.
Get this; The #5 piston was not sitting in the bore straight! It was twisted clock-wise in the bore (bent-rod, twisted rod,)! The piston was noticable just by looking at it. Put it all back together, still doing the same ****. Starting to make me mad.
I am trying to figure out the relationship between the #5 piston being rotated in the bore, the head gasket blown between #3 & #5, and that spark knock sound coming from the motor. Still have good oil pressure.
Any ideas???? Somebody please explain this.
------------------
L98, 3.27 9-bolt, Hooker shorty headers, custom 2.5inch Y-pipe, no cat, 3inch 2chamber flowmaster, JET AFPR, Ported MAF, Best ET: 13.86 @100mph. 1.99 60'
17 inch ROH "ZS" wheels. 17x8.5(front) and 17x9.5 (rear). Firestone Firehawk SZ50s. 245/45/zr17s and 275/40/zr17s. T56
On the way... Radar Blue 89 Formula, T56, Ram Jet 430, Ram Air, 17inch ROHs.
Thread Starter
Member
Joined: Jul 1999
Posts: 327
Likes: 0
From: Stillwater, Oklahoma, USA
I can see that happening. But where is that knocking sound coming from. It has been doing it for like 2 months now, way before the head gasket even blew. It only does it when it is under a load.
------------------
L98, 3.27 9-bolt, Hooker shorty headers, custom 2.5inch Y-pipe, no cat, 3inch 2chamber flowmaster, JET AFPR, Ported MAF, Best ET: 13.86 @100mph. 1.99 60'
17 inch ROH "ZS" wheels. 17x8.5(front) and 17x9.5 (rear). Firestone Firehawk SZ50s. 245/45/zr17s and 275/40/zr17s. T56
On the way... Radar Blue 89 Formula, T56, Ram Jet 430, Ram Air, 17inch ROHs.
------------------
L98, 3.27 9-bolt, Hooker shorty headers, custom 2.5inch Y-pipe, no cat, 3inch 2chamber flowmaster, JET AFPR, Ported MAF, Best ET: 13.86 @100mph. 1.99 60'
17 inch ROH "ZS" wheels. 17x8.5(front) and 17x9.5 (rear). Firestone Firehawk SZ50s. 245/45/zr17s and 275/40/zr17s. T56
On the way... Radar Blue 89 Formula, T56, Ram Jet 430, Ram Air, 17inch ROHs.
Supreme Member
Joined: Jan 2001
Posts: 2,463
Likes: 0
From: Annandale,NJ
it sound like my car, but mine does it becuse the timing was too advanced.
------------------
1987 Black 305 TPI 5spd IROC, G92, 9-bolt 3.45, Lowered, Cat-back, Air Foil, Sub Frames, Huge sways.
AIM: IROC 5spd
http://www.geocities.com/chevy5spdiroc/87Roc.htm
------------------
1987 Black 305 TPI 5spd IROC, G92, 9-bolt 3.45, Lowered, Cat-back, Air Foil, Sub Frames, Huge sways.
AIM: IROC 5spd
http://www.geocities.com/chevy5spdiroc/87Roc.htm
Thread Starter
Member
Joined: Jul 1999
Posts: 327
Likes: 0
From: Stillwater, Oklahoma, USA
I turned the timing down to 4 degrees BTDC.
------------------
L98, 3.27 9-bolt, Hooker shorty headers, custom 2.5inch Y-pipe, no cat, 3inch 2chamber flowmaster, JET AFPR, Ported MAF, Best ET: 13.86 @100mph. 1.99 60'
17 inch ROH "ZS" wheels. 17x8.5(front) and 17x9.5 (rear). Firestone Firehawk SZ50s. 245/45/zr17s and 275/40/zr17s. T56
On the way... Radar Blue 89 Formula, T56, Ram Jet 430, Ram Air, 17inch ROHs.
------------------
L98, 3.27 9-bolt, Hooker shorty headers, custom 2.5inch Y-pipe, no cat, 3inch 2chamber flowmaster, JET AFPR, Ported MAF, Best ET: 13.86 @100mph. 1.99 60'
17 inch ROH "ZS" wheels. 17x8.5(front) and 17x9.5 (rear). Firestone Firehawk SZ50s. 245/45/zr17s and 275/40/zr17s. T56
On the way... Radar Blue 89 Formula, T56, Ram Jet 430, Ram Air, 17inch ROHs.
Joined: Apr 2000
Posts: 1,536
Likes: 322
From: South Windsor, CT
Car: '89 GTA
Engine: ZZ6TPI
Transmission: T56
Axle/Gears: Borg Warner 3.70:1
If you have a bent rod, then the piston will knock against the cylinder wall, especially under load. You could have had a bad gasket for quite a while and not even known it. Sounds like it's time for a new motor.
------------------
89 Transam GTA, 350TPI, auto, 3.27 rear, dual cats, gray.
Magnaflow cat-back,
K&N open element,
Best E.T. 14.63@95mph
------------------
89 Transam GTA, 350TPI, auto, 3.27 rear, dual cats, gray.
Magnaflow cat-back,
K&N open element,
Best E.T. 14.63@95mph
Supreme Member
Joined: Sep 2001
Posts: 6,111
Likes: 53
From: Ontario, Canada
Car: 1988 Firebird S/E
Engine: 406Ci Vortec SBC
Transmission: TH-350/3500stall
Axle/Gears: 7.5" Auburn 4.10 Posi-Traction
A bad fuel injector caused lean fuel mixtures
which overheated the combustion chamber
causing detonation and or preignition.
This stress eventually blew the head gasket,
allowing water to fill the cylinders. Must of started it up with the cylinder full of water and bent the rod. (Hydro lock).
Very bad luck...
which overheated the combustion chamber
causing detonation and or preignition.
This stress eventually blew the head gasket,
allowing water to fill the cylinders. Must of started it up with the cylinder full of water and bent the rod. (Hydro lock).
Very bad luck...
Trending Topics
Thread Starter
Member
Joined: Jul 1999
Posts: 327
Likes: 0
From: Stillwater, Oklahoma, USA
Sorry, this car isnt getting a new motor. Its just gotta get me around for a week or so till I get the 89 to where I can drive it every day. The 89 is the one with the Ram Jet 430 motor and everything is new on it. Cant wait.
Just been racking my brain on the motor in the 88. Yeah, when the 89 is done, Im gonna pull everything that is good off/out of the 88 and then Im gonna roll the shell off of a big cliff somewhere and watch it die!!!
------------------
L98, 3.27 9-bolt, Hooker shorty headers, custom 2.5inch Y-pipe, no cat, 3inch 2chamber flowmaster, JET AFPR, Ported MAF, Best ET: 13.86 @100mph. 1.99 60'
17 inch ROH "ZS" wheels. 17x8.5(front) and 17x9.5 (rear). Firestone Firehawk SZ50s. 245/45/zr17s and 275/40/zr17s. T56
On the way... Radar Blue 89 Formula, T56, Ram Jet 430, Ram Air, 17inch ROHs.
Just been racking my brain on the motor in the 88. Yeah, when the 89 is done, Im gonna pull everything that is good off/out of the 88 and then Im gonna roll the shell off of a big cliff somewhere and watch it die!!!
------------------
L98, 3.27 9-bolt, Hooker shorty headers, custom 2.5inch Y-pipe, no cat, 3inch 2chamber flowmaster, JET AFPR, Ported MAF, Best ET: 13.86 @100mph. 1.99 60'
17 inch ROH "ZS" wheels. 17x8.5(front) and 17x9.5 (rear). Firestone Firehawk SZ50s. 245/45/zr17s and 275/40/zr17s. T56
On the way... Radar Blue 89 Formula, T56, Ram Jet 430, Ram Air, 17inch ROHs.
Thread
Thread Starter
Forum
Replies
Last Post
