while driving at higher RPM's about 50-60 MPH it seems to have a slight vibration. at speeds if i push in the clutch it goes away, and while parked if i rev up the RPM's i also get the same vibration. i have just finished doing alot of work on my truck (72 f-250 4X4). one of which tasks was installing p/s and i had to get different pullys, i wasn't sure if messing with the pullys could cause this. i don't know if this vibration has always been there or not because there were other issues with the drive train that were causing vibrations as well that now are fixed.

thanks for any help in advanced...Russ

 

mabe your flywheel or harmonic balencer is out of balence

 

i think you're right, but what would be the best way to fix it? and is it something i can do myself?

thanks...Russ

 

the balencer isnt that hard just look and check the rubber goin around betwween the to parts. if it looks like its riped or coming out mabe the outer part has sliped. most parts stores could order a new one. as for the flywheel youd have to drop the trans and pull the flywheel and take it to a shop that can machine it back to TRUE and balence it. this would be a great time to put in a new clutch also

 

i hope it's not the flywheel, i just had my transfercase pulled out last week, i thought all my heavy work was done. i think i'll check the ballancer first, maybe i'll get lucky.

thanks...Russ

 

Russ, That info would have nice to have had in your first post.

Pulling your TS you dis-connected the drive shafts, and you may need to rotate one or both of them 180º to get them back into phase. One of the U-joints may not be centered in the yoke also.

Check it out.

John

 

[QUOTE=jowilker]Russ, That info would have nice to have had in your first post.

rite on john! that can couse a vib but he said it do's it with the clutch pushed in and just revin it up.not tryin to argue or nothin.after all i do agree with ya 99% of the time

 

Vibration dampner; mis-aligned engine/transmission; clutch throwout/pilot bearing; engine/trans/transfer case rubber mounts; clutch pivots and/or bushings; scored flywheel.

 

How did we get the harmonic balancer (crank damper) from the front of the crank to the flywheel?

If you had a bad clutch disk or the pilot bushings worn the input shaft would wobble and cause a vibration that would come and go at random when the clutch engaged.
With vibration in neutral the first I would remove the pulley drive off the damper and run it up in neutral again. To have the damper vibrate that much you should see it wobbling or where it has slipped. If the same results I would suspect the clutch pressure plate.
Install a stack of washers with a longer bolt securing pressure plate to flywheel then run up in neutral, do this on the other 5 locations to see if you can get a reduction in vibration provided it's in the right location.
Clutch basket out of balance, warped or coming apart?
Better to test than throw a bunch of new parts at it.

 

thanks for all the help guys, as soon as i get some time i'll dig into it and see what find.


thanks again...Russ

 

The engine is internally ballanced. The harmonic balancer is zero balanced. Meaning that even if it slipped, generally it would not change the balance characteristics. Put a timing light on it and see if the timing marks line up. If you think it's the pulleys (which are also zero balanced) take off the belts and start it.
I too, would think clutch pressure plate.
If the u-joints and driveshafts were out of phase it would change with MPH's not RPM's.

 

A zero balanced damper will have holes drilled in general to correct for the casting imbalance, yes they can slip that much and cause a little imbalance
or vibration problem. Now to have a clutch basket go out of balance due to twisting (long arm), cracks, twisted baskets, broken springs or in general the pivot pins worn which doesn't take much you'll have a shaker. This shakes even with a heavy tranny plus a transfer hanging on the end, now that's some imbalance to overcome that heavy mass think about it.
To miss match parts you'll create a real shaker and bearing destroyer.
I may be repeating here but baskets are crap at best compared to years ago, now thinner gauge metal (more cracking) unless you build a custom basket yourself. Ford even installed remans in new vehicles under warranty, yes our loved Ford dealers.
Yes it can be done to have a soft clutch pedal with a U joint snapping clutch if you machine the arms and add weights, needle bearing pivot points and load it up with 9 springs not skipping to 6 as well pre testing for even release clearance around the pressure plate and installed arm height.
Now this sucks as I have a slush box in my truck thinking about stirring the stick, well the other 5 vehicles are are sticks.