Bananarama! Vibration!!!!!

sinny · Post by **sinny** » Sat Mar 07, 15 5:20 pm

I'm at the end of my rope now!!

Just installed the different pig with 3.23 gears, fresh oil, the half shaft adjuster lock in place & the Bananarama! vibration is STILL THERE!!!!

The vibration comes in at about 60 mph & is like driving over ripped concrete which shakes the whole car!

I ran it on jack stands to 70mph without a driveshaft & no vibration, I have replaced the driveshaft - no difference! Angle of the pig & trans are almost dead straight. Ran without wheels or brake drums - still there!

Now completely out of ideas!

Pete · Post by **Pete** » Sat Mar 07, 15 5:22 pm

Have you changed the Prop??

sinny · Post by **sinny** » Sat Mar 07, 15 5:24 pm

Yep got a 2nd hand one.

Pete · Post by **Pete** » Sat Mar 07, 15 5:27 pm

What about that suspect half shaft?

sinny · Post by **sinny** » Sat Mar 07, 15 5:28 pm

When I had a close look it seemed fine.

Do you know anywhere that can balance a prop Pete? Wonder if it is that.

John · Post by **John** » Sat Mar 07, 15 5:30 pm

Can you drive through the vibration Shaun?

Pete · Post by **Pete** » Sat Mar 07, 15 5:31 pm

Bailey Morris at Eaton Socon, do not use Reco-Prop in Luton.........

sinny · Post by **sinny** » Sat Mar 07, 15 5:31 pm

I've got to 90 & it's still there.

Cheers Pete, I'll give them a ring Monday.

John · Post by **John** » Sat Mar 07, 15 5:33 pm

Oh cricky,
I was just wondering as my last 2 have both had a bit of vibration around the 70 mph mark but that goes as you either speed up or slow down a bit.

charger01 · Post by **charger01** » Sat Mar 07, 15 5:47 pm

We had the same fault here . It was the gearbox.

Dave-R · Post by **Dave-R** » Sat Mar 07, 15 6:20 pm

sinny wrote:Angle of the pig & trans are almost dead straight.

That won't work.

Trans/crank centreline should be angled slightly down towards the rear. Pig should be angled slightly up at almost the same angle towards the front (but very slightly nose down from that angle).

You need something more than one degree and less than three degrees angle in the UJ at each end to run smoothest. Under load (driving) the nose lifts slightly hence you need it slightly down from the correct angle when static.

If the UJs are not at the same angle each end of the prop when driving they have to flex at two different speeds and cause vibrations.

Adrian Worman · Post by **Adrian Worman** » Sat Mar 07, 15 6:34 pm

If you keep it in 2nd and get it past 60 does it do it then?
Or is it just in 3rd?

On the driveshaft balancing idea I had the same with a prop I shortened in my Chally a few years ago.
It only really became apparent at higher road speeds, I thought that was gearbox bearings Bananarama! but after running the car up to 85-90 in 3rd as well as 4th and experiencing the same vibration, I balanced the prop and it all went away.

Don't assume those shafts are straight either, just cos they look good get em checked against a straight edge at a machine shop.

Pete · Post by **Pete** » Sat Mar 07, 15 6:35 pm

Dave is right on this...

Another (left field) thought....

The Engine can actually be put in the bay on the cock so even if you had the phasing correct that Dave mentions, perhaps it is possible to have the prop out of phase in a horizontal plane.

The Schumaker site details the precise setting off the motor on the "K" frame mounts. I know it is 2.5" off to the right, but I have forgotten the crank CL off the "K" frame measure......

autofetish · Post by **autofetish** » Sat Mar 07, 15 7:13 pm

Take the whole dana 60 and prop off mine and drive around the block

db · Post by db » Sat Mar 07, 15 7:34 pm

Do you know for definite that your wheels are balanced? I went through all this with mine mate. I'd assumed my wheels were ok. When I got them checked they were so far off the balance machine couldn't even measure it!
I agree with Dave on the prop but if you can borrow a pair of wheels it's an easy thing to try

Mopar Muscle Association UK

Bananarama! Vibration!!!!!

Bananarama! Vibration!!!!!

Re: Bananarama! Vibration!!!!!