66 Mustang with Heavy Vibration
Thread Starter
Joined: Oct 2017
Posts: 1
From: ca
66 Mustang with Heavy Vibration
Hello everyone, I recently purchased a 66 mustang that has had a 90-91 302 engine installed. There is some very heavy vibration felt in the car at 2000rpm and higher - even while in neutral. I've been told not to drive the vehicle as this shaking will damage the engine. Ofcourse the seller who sold me the car never mentioned this issue and I just thought it was how a old classic feels. After doing some research I have found out that either there is a wrong harmonic balancer or flywheel installed. In the worst case I may have a bad engine. I have gathered all the serial numbers off the engine (F16E) the serial number off the harmonic balancer (E4TE-A3A) and the flywheel (RF-E1ZR6380.) I also attached pictures of the serial numbers just in case I am not reading them correctly lol
If anyone has any knowledge about this vibration and can help that would be so greatly appreciated. Im hoping the harmonic balancer or flywheel is not correct and that I don't have an engine rebuild ahead of me. Any ideas?
If anyone has any knowledge about this vibration and can help that would be so greatly appreciated. Im hoping the harmonic balancer or flywheel is not correct and that I don't have an engine rebuild ahead of me. Any ideas?
6th Gear Member
Joined: Dec 2005
Posts: 5,212
From: Hills of California
a 91 engine should use the 50oz weight.
1) check that the damper wheel has a key installed under it to properly align it
2) check that its using 50oz and the weight is installed proper...some race dampers use removable weights.
3) is that a t5 trans? what tag is that?
4) what motor mounts are you using? There needs to be proper rubber isolation between the frame and the engine provided by the motor mount if its steel on steel its going to suck.
1) check that the damper wheel has a key installed under it to properly align it
2) check that its using 50oz and the weight is installed proper...some race dampers use removable weights.
3) is that a t5 trans? what tag is that?
4) what motor mounts are you using? There needs to be proper rubber isolation between the frame and the engine provided by the motor mount if its steel on steel its going to suck.
Gentleman's Relish
Joined: Feb 2005
Posts: 13,189
From: AZ
a 91 engine should use the 50oz weight.
1) check that the damper wheel has a key installed under it to properly align it
2) check that its using 50oz and the weight is installed proper...some race dampers use removable weights.
3) is that a t5 trans? what tag is that?
4) what motor mounts are you using? There needs to be proper rubber isolation between the frame and the engine provided by the motor mount if its steel on steel its going to suck.
1) check that the damper wheel has a key installed under it to properly align it
2) check that its using 50oz and the weight is installed proper...some race dampers use removable weights.
3) is that a t5 trans? what tag is that?
4) what motor mounts are you using? There needs to be proper rubber isolation between the frame and the engine provided by the motor mount if its steel on steel its going to suck.
If it turns out to be the dampner and you replace it, if the problem goes away, you may still want to drop the pan and inspect the rod and main bearing for odd wear. You can cause excessive wear at either end of your crank from an imbalance depending on how bad it was and for how long it was driven like that.
Last edited by Derf00; Oct 25, 2017 at 02:04 PM.