VIBRATIONS?!

Afternoon All,

Having had a few little niggling problems with the ol' hippo ive been working through them slowly.

I had some REALLY bad centre bearings which I changed, and and the knocking I had while cornering went, great, however, I have gained a vibration between 50 and 70 which has now replaced it. (there was nothing previously, no vibrations)

there is aboslutely NOTHING up to 45/50, but starts at 50, then gone just after 70.

Is this likely uncovering another issue with the prop, or could it be elsewhere.

Thanks in advance for the wisdom!!!

Sounds like wheel or wheels out of balance.

Either get them checked or, cheaper, put rear on front and see if it changes.

Also, get someone to rock steering wheel while you feel the track rod ends for play and wear.

ArchN3m3sis said:

Afternoon All,

Having had a few little niggling problems with the ol' hippo ive been working through them slowly.

I had some REALLY bad centre bearings which I changed, and and the knocking I had while cornering went, great, however, I have gained a vibration between 50 and 70 which has now replaced it. (there was nothing previously, no vibrations)

there is aboslutely NOTHING up to 45/50, but starts at 50, then gone just after 70.

Is this likely uncovering another issue with the prop, or could it be elsewhere.

Thanks in advance for the wisdom!!!

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How are the tyres? Same make all round with least worn on the rear?

Nodge68 said:

How are the tyres? Same make all round with least worn on the rear?

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yeah, always changed as a set, all matching, no cheap sh!te, least worn on the rear. i thought to myself its the props, im wondering if the seperation, (which wasnt too fun on the from prop anyway, required some heat becuase it was rusted on pratically despite it being done by a garage 4ish years ago ) has upset something.....

ArchN3m3sis said:

yeah, always changed as a set, all matching, no cheap sh!te, least worn on the rear. i thought to myself its the props, im wondering if the seperation, (which wasnt too fun on the from prop anyway, required some heat becuase it was rusted on pratically despite it being done by a garage 4ish years ago ) has upset something.....

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Good. It's surprising how few take care of there tyres.
When you fitted the VCU, was it set on the centerline of the vehicle, with the bearings at a perfect 90° to the VCU shafts?

Have you done the one wheel up test for the VCU ? Tight VCU can cause vibration and strange rear tyre wear pattern.

Nodge68 said:

Good. It's surprising how few take care of there tyres.
When you fitted the VCU, was it set on the centerline of the vehicle, with the bearings at a perfect 90° to the VCU shafts?

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yeah it was, meticulously lined up.

andyfreelandy said:

Have you done the one wheel up test for the VCU ? Tight VCU can cause vibration and strange rear tyre wear pattern.

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ive been told by Bell Engineering thats not a definative test

andyfreelandy said:

Sounds like wheel or wheels out of balance.

Either get them checked or, cheaper, put rear on front and see if it changes.

Also, get someone to rock steering wheel while you feel the track rod ends for play and wear.

Click to expand...

i did think it may be wheel related since i can drive through it, im gonna whip it up to local garage today to have them check the rear wheels, because it is most definetly not the front wheels

ArchN3m3sis said:

ive been told by Bell Engineering thats not a definative test

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Bell's won't be able to do a definitive test either.

Their test has been on YouTube since 2010...



In the description for that test they say "This is a reconditioned Freelander VCU being tested to show how a correctly operating VCU should behave.".

In concept, it is exactly the same as the 1WUT. It does though remove the diff, wheel bearings and brakes as possible interference with the test. The diff and bearings are negligible. Obviously if your brakes are binding, then that will interfere - just make sure they are not.

So their test, offers minimally more accurate results, but you have to remove the props from the car to do the test and have a setup to secure it while the test is done. Its a test that people will not do.

The 1WUT is quick and simple to do. If there are any problems, it can not give you a false positive result - only a false that the unit needs replacing - as I say, if your brakes are binding - so check the brakes and retest (and its rare anyway).

But neither offer a definitive result - only indicative. For some reason (commercial?) they think their test is special, it isn't!

ArchN3m3sis said:

ive been told by Bell Engineering thats not a definative test

Click to expand...

Bell were an integral to the OWUT being developed, as it's a vehicle base equivalent of there own test. They have since dismissed the OWUT as not suitable, even though it's basically the same test as theirs.

The only correct way to test the VCU is to measure the torque output, while the input side is being spun at 400 RPM. This would require a very large lathe and some form of torque measuring device, the former being beyond the scope of a home mechanic, unless they're heavily into metalworking.

All we have is the OWUT, which for most is a good indication that a VCU has stiffened.

Well I whipped it round to mates garage and threw it up in the air, and found that the damper on the VCU has split, so that's what's causing the issue with the vibration...... Only evident with brand new bearings and something I didn't think to check while it was all off. So I've dropped the prop off tonight, I'm gonna removed the damper and then put it all back. I have noticed the boot on the front prop is slightly damaged. Do you know if there's a part number for that boot?