08-25-2019 | #1 |
Join Date: Nov 2011
Location: Dunbarton NH
Posts: 7,485
|
Motor mounts?
I've noticed my shifter seems to lift noticeably when I drop the hammer on Bertha. Motor mounts?
|
08-25-2019 | #2 |
Join Date: Jun 2006
Location: Sparks, NV
Posts: 2,852
|
Re: Motor mounts?
Possibly or loose C frame (Beam) bolts at the trans or both...
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. Last edited by Ccmano; 08-25-2019 at 09:00 PM. |
08-25-2019 | #3 |
Join Date: Sep 2016
Location: Ocala, FL
Posts: 899
|
Re: Motor mounts?
C beam bolts. The C beam ties the trans to the differential and the torque lifts the tranny if they are loose. Others will comment I am sure.
__________________
Steve Young 1991 ZR-1 Quasar Blue Metallic/Black #729 Second Owner 1991 ZR-1 Dark Red Metallic/Black #2040 SOLD 1990 ZR-1 Dark Red Metallic/Saddle #1670 SOLD Double your happiness.....complain half as much. |
08-26-2019 | #4 |
Join Date: Aug 2006
Location: McLean, VA
Posts: 3,723
|
Re: Motor mounts?
Steve,
I would check the C beam bolts first. |
08-26-2019 | #5 |
Join Date: Nov 2011
Location: Dunbarton NH
Posts: 7,485
|
Re: Motor mounts?
I'll put it up on the lift and check it out. Anything special about tightening them?
|
08-26-2019 | #6 | |
Join Date: Aug 2006
Location: McLean, VA
Posts: 3,723
|
Re: Motor mounts?
Quote:
It is possible to use torque wrench without removing the exhaust. I can't remember if I used "U"joint extension to get around the exhaust or crow feet open end. If using crow feet, I would stay a shade below 40 lb-ft since you will be eccentric relative to the extension. |
|
08-26-2019 | #7 |
Join Date: Aug 2009
Location: South Dakota/California
Posts: 3,797
|
Re: Motor mounts?
You should install C4 Beam Plates from ZFdoc as described here ........Post 39 - C4 Beam Plates and Installation
www.zfdoc.com
__________________
Left Clickable links -Solutions- LT5 Modifications/Rebuild Tricks Low Mileage ZR-1 Restoration 1990 Corvette (L98) Modifications LT5 Eliminated Systems LT5 Added Systems LT5/ZR-1 Fluids 1995 LT5 SPECIFIC TOP END REBUILD TRICKS Last edited by Dynomite; 08-26-2019 at 02:03 PM. |
08-26-2019 | #8 |
Join Date: Jun 2006
Location: Sparks, NV
Posts: 2,852
|
Re: Motor mounts?
While the C Beam bolts are the most likely culprit and the ZFDoc beam plates the best solution (wouldn’t drive a C4 without them) don’t assume your engine mounts are good. They need to be inspected. 30yr old oil filled rubber right next to the exhaust manifolds is a bad combination. Every single C4 I’ve owned and many I’ve inspected have had at least a bad right mount if not both. If they are original, dollars to donuts at least one is bad.
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. |
08-26-2019 | #9 |
Join Date: Nov 2011
Location: Dunbarton NH
Posts: 7,485
|
Re: Motor mounts?
Thanks for all the input.
Bill C Beam plates have already been installed. I'll check the motor mounts, Pete had the engine out last year, I would have thought he would have noticed. |
08-26-2019 | #10 |
Join Date: Nov 2011
Location: Dunbarton NH
Posts: 7,485
|
Re: Motor mounts?
C Beam is not obviously loose, but I did not put a socket to them.
Motor mounts? Floor jack and 2x4 under the oil pan? |
|
|