03-19-2019 | #11 |
Join Date: Apr 2007
Location: Northern VA
Posts: 2,661
|
Re: Connecting rod bolts
FSM says to always install new connecting rod bolts when ever they are removed for any service.
Jerry has high quality replacement ARP bolts http://www.jerrysgaskets.com/bolt-se...new-90-95-9b1/ Sent from my iPhone using ZR-1 Net Registry
__________________
Phil Wasinger 1994 Torch Red ZR-1 WAZOO Member George Braml Intake |
03-19-2019 | #12 |
Join Date: Jun 2006
Location: Sparks, NV
Posts: 2,852
|
Re: Connecting rod bolts
Rod knock is ultra rare on these engines. I would make sure there isn’t some sort of imbalance at that rpm and load causing the knock from the dual mass flywheel. Fuel injectors and ignition coils/wires/plugs are possible culprits. Hard to say without actually hearing it.
Good luck. H
__________________
90'ZR-1 #1461 Red/Black Ported Intake, Degreed Cams, OBX Headers & Exhaust, Fidanza FW, Secondary Delete, Custom tune, C6 GS Wheels. Sold 08 C6 Z51 Crystal Red Metallic Sold Vararam Intake, Tune, Sold 05 C6 Z51 Red/Black Sold 90'ZR-1 #1723 Black/Gray Sold but not forgotten 91' Z51 L98 White Vert. My First, you always remember your first. Sold. |
03-19-2019 | #13 |
Join Date: Jan 2015
Location: NYC
Posts: 30
|
Re: Connecting rod bolts
Take the rod bolts out of the equation.
When they go, THEY REALLY GO..... Quick check on piston pin ,bolts n bearings is disconnecting 1 ignition wire at a time n coming up on RPM. If the oil pressure was low after repairing oil cooler,you got bearing issue. If you "dump" the clutch on/off with emergency brake on you will hear flywheel n balancer if that's the issue Tensioner n shoes depend heavily on oil pressure by the way-unless failing as we speak Last note: crank engine w/out ignition n sit in engine bay just in case its something silly like belt tensioner |
03-19-2019 | #14 |
Join Date: Mar 2015
Location: New Zealand
Posts: 386
|
Re: Connecting rod bolts
|
03-20-2019 | #15 |
Join Date: Feb 2012
Location: Ledyard,CT
Posts: 8,256
|
Re: Connecting rod bolts
Has someone changed the transmission Fluid?
|
03-20-2019 | #16 |
Join Date: Sep 2008
Location: Mullica Hill, New Jersey
Posts: 2,593
|
Re: Connecting rod bolts
Agree fully with:
CCMANO BYEBYE2U GT COLLINS and BIG JOHN While certainly not impossible, it is highly improbable. When the hose let go, the oil would have begun to make significant smoke had he not noticed it earlier, and likely long before any engine damage. Lower end failures are extremely rare. Flywheel is the prime culprit, caused by some ignition issue or injector issue. Stop looking for pink leopards with stripes instead of spots first, and look for cats and dogs instead. While you may indeed be absolutely correct, history suggests other causes are far more likely. Whenever I have had customers bring in or call about LT-5 knocks, it has always been traced back to the dual mass flywheel making racket due to another factor. Good Luck, and let's check the routine stuff first. Marty |
03-20-2019 | #17 | |
Join Date: Apr 2007
Location: Lake Bluff, IL
Posts: 2,096
|
Re: Connecting rod bolts
Quote:
__________________
2016 Long Beach Red Z06 #10281 "POPS Z" 1995 Polo Green #409 "WARP TEN"--Haibeck 350/510 package, 4.10s, Hurst, Stock Exhaust with QTP Cutouts --Sold but still running strong 1993 Quasar Blue #161 "HIL KING" --Sold but still running strong, now with more than 120,000 miles 1967 Marlboro Maroon/Saddle Corvette Coupe 300 hp/4-spd --Sold a long time ago ZR-1 Net Registry Founding Member #95 NCM Lifetime Member Favorite Quote--Attributed to Mickey Thompson: "Too Much Horsepower is Almost Enough" |
|
03-20-2019 | #18 |
Join Date: Dec 2003
Location: Arcadia,OK
Posts: 3,394
|
Re: Connecting rod bolts
Rod knock is most prominent at “no-load” condition like at idle. The knock will subside with load. For example; set emergency brake, idle engine, slowly engage clutch. Knock will subside as idle speed is pulled down, i.e. when load is applied.
I have net seen or heard of a true, blown oil cooler hose. All failures I am aware of were crimp leaks that seeped to the outside of the hose, or just under the outer rubber sheath. A leak under the outer sheath will cause a bubble that will ultimately burst & appear to be a fully ruptured hose, but is not. The working part of the hose beneath is layered, fabric/rubber reinforced. Low oil pressure will cause lifter rattle that sounds like a machine gun. No one in their right mind would continue to drive with that condition. Very unlikely that the "blown" oil cooler hose resulted in a massive loss of oil, significant enough to cause engine damage. From your description of the noise conditions, I don’t think it’s a rod knock. A dual mass flywheel knock is most often associated with an engine miss. Inspect the spark plugs, look for anything unusual, different coloration or damage. Insofar as checking rod bearings; if you see damage from lack of lubrication, I consider that as an indication of main bearing condition also. To access the mains requires complete disassembly of the engine.
__________________
Jerry Downey JERRYS LT5 GASKETS & PARTS http://www.jerrysgaskets.com 1994 ZR-1, Black/Black, Lingenfelter Aerobody, 416cu in, 3.91 gears, coil-over susp, Brembo brakes, etc. 2016 Black-Red, 3LT-Z51 Auto 8-speed. Last edited by A26B; 03-20-2019 at 07:41 PM. |
03-20-2019 | #19 |
Join Date: Sep 2018
Location: Groton, CT
Posts: 384
|
Re: Connecting rod bolts
Thanks for all the suggestions.
Since the injectors are 92 originals, that's first on the list this weekend (parts coming from Jerry's). I know at least one is going. One thing at a time until I get it figured out. The car has less than 20K miles. Should I do coils while I'm in there?
__________________
1992 ZR1 #442, 2 tops, White, White, Haibeck 415, 3.90 gear, Coilovers 2018 Audi RS5, 2.9 V6 Twin Turbo, Auto, Black, Black 2021 Audi Q3, 2.0T, 8 spd Tiptronic, Navarro Blue metallic, Pearl Beige |
03-21-2019 | #20 |
Join Date: Jan 2015
Location: Marietta, GA USA
Posts: 1,160
|
Re: Connecting rod bolts
|
|
|