427/390 vibration

[James A. Lloyd Jr.]

at 3000-3300 rpms i'm recieveing a hard vibration. it's hard to tell were it is coming from, it feels thru steering wheel floor board and drive train

fyi ....recent work done on car......
8 mths ago new center force clutch,rebuilt trans (3 pilot bearings, 2 throw out bearings since clutch put in, 1st piolot beadring had roller bearings, came apart, the last two were solid. the 2nd started whinning when clutch pedal pressed mecahnic said grease broke down??? 3rd put in two days ago)

all new steering

new alum. radiator and fan clutch( now runs 175-180 before 210-230)

new headers , noticed some vibration when they were installed 2 mths. ago. seems to be worse since i picked it up 2 days ago from pilot bearing install

wheels and bearings check out ok

[D S.]

Re: 427/390 vibration

Checked the rear transmission mount to see if it's not broken loose from the rubber pad? Engine mounts?

[D S.]

Re: 427/390 vibration

Checked the rear transmission mount to see if it's not broken loose from the rubber pad? Engine mounts?

[John H.]

Re: 427/390 vibration

All the pilot bushing/bearing replacements would indicate that the bellhousing isn't centered within spec to the crank centerline, and the throwout bearing replacements indicate incorrect clutch adjustment (inadequate pedal free play, which will fry the throwout bearing).

Is the vibration engine rpm-sensitive, or car speed sensitive?

[John H.]

Re: 427/390 vibration

All the pilot bushing/bearing replacements would indicate that the bellhousing isn't centered within spec to the crank centerline, and the throwout bearing replacements indicate incorrect clutch adjustment (inadequate pedal free play, which will fry the throwout bearing).

Is the vibration engine rpm-sensitive, or car speed sensitive?

[Albert P.]

Re: 427/390 vibration

For what it's worth, I have a SB but had a vibration in the same range; turned out to be fan clutch.

[Albert P.]

Re: 427/390 vibration

For what it's worth, I have a SB but had a vibration in the same range; turned out to be fan clutch.

[Albert P.]

Re: 427/390 vibration

Disconnect belts and run engine to rpm to see if that eliminates the problem

[Albert P.]

Re: 427/390 vibration

Disconnect belts and run engine to rpm to see if that eliminates the problem

[James A. Lloyd Jr.]

Re: 427/390 vibration

rpm sensitive

[James A. Lloyd Jr.]

Re: 427/390 vibration

rpm sensitive

[James A. Lloyd Jr.]

Re: 427/390 vibration

all mounts are ok

[James A. Lloyd Jr.]

Re: 427/390 vibration

all mounts are ok

[Dick W.]

Re: 427/390 vibration

You mentioned that you noticed some vibration after the headers were installed. I would check for pipes or headers hitting the frame.

[Dick W.]

Re: 427/390 vibration

You mentioned that you noticed some vibration after the headers were installed. I would check for pipes or headers hitting the frame.