View previous topic :: View next topic |
Author |
Message |
Larry Epperson Bel Air

Joined: 05 Dec 2006 Posts: 300 Location: Dallas
|
Posted: Sat Dec 15, 2018 8:53 pm Post subject: Motor Mount Problem |
|
|
I have had two failures on my motor mounts the latest coming after only 3000 miles. (Bowling Green Kentucky longest trip)
I have side motor brackets on my 57, Energy Suspension ENS-3.1114R motor mounts, 350 Engine and Patriot H-8025 exhaust headers. This is the same set up I installed 10 years ago.
I sent the latest set to Energy Suspension for a decision or what the problem is/was. The response was that the mounts were getting too HOT and I should install a heat shield to protect the polyurethane! They have 'melted' somewhat but shouldn't they work as installed?
I know there are several of you that are using these Patriot Headers and maybe even using the ENR mounts.
??Are you having the same problem? Maybe you should check your mounts
My exhaust heat should not be any hotter than anyone else.
Please give me your comments before I buy another set.
Thank You
Larry Epperson _________________ in my Garage:
1957 Chevy BelAir
1949 Chevy Truck
Thought for the day-
Horsepower: "If a little is great, and a lot is better, then way too much is just about right |
|
Back to top |
|
 |
acardon Bel Air
Joined: 12 Jul 2005 Posts: 273 Location: Southlake, Tx.
|
Posted: Sun Dec 16, 2018 3:16 pm Post subject: |
|
|
Larry, have you checked the header temps with a inferred temp gun? A rich mixture can cause them to get hotter than normal. |
|
Back to top |
|
 |
David Graves Site Admin

Joined: 02 Jun 2005 Posts: 1387 Location: Warsaw, TX
|
Posted: Sun Dec 16, 2018 7:33 pm Post subject: |
|
|
rich mixture = hotter ???
with my dragster, lean gets it hot and will burn electrodes, rich will cool the combustion chamber ... ???
a quick Google search finds two results -
Most overheating issues related to air/fuel ratios are the result of a lean mixture, which causes the cylinders to run hotter.
A rich mixture will cause the vehicle to run hot. It will cause a clogging up off the catalyst resulting in the degradation of the honeycomb in it.
Bottom line - ? I have no clue other than my own experience with drag racing and lean gets the chamber hot .. _________________ In My Garage -
'55 Bel Air Hardtop
'55 Bel Air 2dr Sedan
'56 Corvette
'67 Camaro RS
'69 Blown 427 nostalgia front engine dragster
'17 Indian Chief Vintage |
|
Back to top |
|
 |
Larry Epperson Bel Air

Joined: 05 Dec 2006 Posts: 300 Location: Dallas
|
Posted: Sun Dec 16, 2018 8:49 pm Post subject: |
|
|
No, I haven’t checked the temp of headers and will need to check fuel/air mixture plus timing
Gives me some things to check out
Thank you and will give update. Right now no supports on to to the check. I can put the old ones in to check out or maybe go solid mounts which doesn’t correct the potential problem ! _________________ in my Garage:
1957 Chevy BelAir
1949 Chevy Truck
Thought for the day-
Horsepower: "If a little is great, and a lot is better, then way too much is just about right |
|
Back to top |
|
 |
David Graves Site Admin

Joined: 02 Jun 2005 Posts: 1387 Location: Warsaw, TX
|
Posted: Sun Dec 16, 2018 8:54 pm Post subject: |
|
|
Your problem is not unique .. there are several threads on forums about this issue .. and seems the fix is solid mounts or change headers, after making sure there isn't some extreme temperature thing going on ..
https://www.corvetteforum.com/forums/c3-tech-performance/2703448-poly-motor-mounts-melted.html _________________ In My Garage -
'55 Bel Air Hardtop
'55 Bel Air 2dr Sedan
'56 Corvette
'67 Camaro RS
'69 Blown 427 nostalgia front engine dragster
'17 Indian Chief Vintage
Last edited by David Graves on Sun Dec 16, 2018 9:02 pm; edited 1 time in total |
|
Back to top |
|
 |
acardon Bel Air
Joined: 12 Jul 2005 Posts: 273 Location: Southlake, Tx.
|
Posted: Sun Dec 16, 2018 8:55 pm Post subject: |
|
|
David's right, I had it backwards. Lean mixture can cause hot headers.
Have you tried rubber, I would think solid mounts would be noisy and vibrate the whole car. Can you put a shield between the header and mount? |
|
Back to top |
|
 |
Larry Epperson Bel Air

Joined: 05 Dec 2006 Posts: 300 Location: Dallas
|
Posted: Sun Dec 16, 2018 9:43 pm Post subject: |
|
|
I have a shield designed to fit between the poly mount and the backing plate with a ‘turn up’ about 2”. (5”x 8”) 22 ga sheet steel. Looks good and should work but still need to make any lean conditions. Changed needle rods/jets with rebuilt engine may need to go back to original or even richer. I bought a complete needle/jet kit for the Edelbrock Carb. Easy enough to do just takes a few minutes _________________ in my Garage:
1957 Chevy BelAir
1949 Chevy Truck
Thought for the day-
Horsepower: "If a little is great, and a lot is better, then way too much is just about right |
|
Back to top |
|
 |
|