Sponsored Content
How to tell if motor mounts need replacing? 1976L with 54,000 miles.
Be the first to like this post
Sign In to Like this post
Sign In to Like this post
SPONSOR AD:: (Our Sponsors help support Vette Registry)
Do a visual inspection of the rubber part of the mount. If they mushed down to the point whereas there is metal to metal contact they should be replaced. Especially on the passenger side. The engine torques to the right whenever you push the throttle putting most of the pressure on that side.
With the hood open put it in gear and nudge the throttle and see if the driverside of the engine rises unusually high. Thats the side that likes to pull the rubber apart since the engine torques to the right. You most likely won't notice a ripped mount since the weight of the engine keeps them compressed.
I recommend not buying those cheap OEM style rubber isolated mounts. They fail fairly quickly I found though past experiences. Spend the money and buy some decent polyurethane mounts. You really won't notice any extra vibration with the poly ones.
Check your transmission mount while your at it too. Those can make some clunking noises under there if its bad.
GEN III 5.7L "LS6" Engine swap
TKO500 5 spd.
3.54 Dana 44
'69 "N11" Sidepipes
Borgeson Steering Box
Born 8/1981
Sequence #3975
Click here to see more pics of my Vette on CarDomain.
Lifetime Member #26
Borgeson Steering Box
Born 8/1981
Sequence #3975
Click here to see more pics of my Vette on CarDomain.
Lifetime Member #26
Be the first to like this post
Sign In to Like this post
Sign In to Like this post
Sarge81 said:
Do a visual inspection of the rubber part of the mount. If they mushed down to the point whereas there is metal to metal contact they should be replaced. Especially on the passenger side. The engine torques to the right whenever you push the throttle putting most of the pressure on that side.
With the hood open put it in gear and nudge the throttle and see if the driverside of the engine rises unusually high. Thats the side that likes to pull the rubber apart since the engine torques to the right. You most likely won't notice a ripped mount since the weight of the engine keeps them compressed.
I recommend not buying those cheap OEM style rubber isolated mounts. They fail fairly quickly I found though past experiences. Spend the money and buy some decent polyurethane mounts. You really won't notice any extra vibration with the poly ones.
Check your transmission mount while your at it too. Those can make some clunking noises under there if its bad.
Then put it in reverse and see if the other side rises....
Be the first to like this post
Sign In to Like this post
Sign In to Like this post
Thanks for the reply. If they need replacing, can they be replaced with motor in the car?
Be the first to like this post
Sign In to Like this post
Sign In to Like this post
I have done them in the car. It's not fun. I jacked up one side at a time to do them. If I remember correctly…the front 2 spark plug wires (both sides) run between the engine block and the upper half of the motor mount. That would be the best time to change out plug wires if needed and route them like the factory did.
GEN III 5.7L "LS6" Engine swap
TKO500 5 spd.
3.54 Dana 44
'69 "N11" Sidepipes
Borgeson Steering Box
Born 8/1981
Sequence #3975
Click here to see more pics of my Vette on CarDomain.
Lifetime Member #26
Borgeson Steering Box
Born 8/1981
Sequence #3975
Click here to see more pics of my Vette on CarDomain.
Lifetime Member #26
Be the first to like this post
Sign In to Like this post
Sign In to Like this post
in Forum: C3 Engines, Driveline and Handling
Sponsored Content