Yet another propshaft question

[sh55123]

Hi,

I have recently had issues with my 325i Sport (tech 2). It needed a new clutch, so I took it to a garage recommended by my Dad, and while they were doing the work they noticed that the guibo and centre support bearing were knackered. I was very wary of them doing the work, and told them to ensure they mark the prop before splitting it etc, but nonetheless gave them the go ahead.

When it came back, it had moderate vibration coming through the floor starting at about 37mph, and getting worse as speed increased. Not trusting the garage, I got under the car myself to check all the usual culprits.

The guibo was on fine (arrows facing flanges, and bolts following arrows etc), but sure enough the prop was a spline or two out of line. I took it all out, realigned the prop (original white dots still there) and checked the plane of the UJ's to make sure all was good. I pretensioned the centre bearing towards the front of the car by 6mm too.

After reassembly, the vibration was far better, but I had a strange noise coming from underneath and a loud whine (starting around 20mph and disappearing around 40 that got better as the car warmed up). I suspected they had fitted a q-drive centre bearing, so sourced a new one (Meyle from C3) and took it all apart again.

The car is better again now, but I still have this strange whine (far less pronounced, and disappears after just a few minutes), and I still have this damn vibration between 37 and 45. It does go away completely, but is so annoying.

I have since bought a whole used prop (thanks Trevor (B7)), and am just about to try again, so have a couple of questions.

1) Is there anything else I should check before I give up on the original prop?

2) As I did not remove the prop in the first place, is gearbox output flange to prop flange alignment something I should worry about?

3) Are Meyle centre bearings OK?

4) Can anything else cause this type of vibration? It was fine before the car went in.

Oh by the way, the guibo 'appears' to be genuing - I can't remember the three letter acronym stamped into it, but it is the one mentioned everywhere on the 'zone as being OEM, and I am sure it also had a BMW stamp on it

Any help or advice greatly appreciated!!

Steve

[Brianmoooore]

Only thing I can think of is to check the location of the the front of the propshaft.
There is a spigot that projects from the front of the gearbox output shaft and locates in a centering sleeve in the front of the prop. Any damage to this and the prop will run slightly off centre at the front.
Worst case scenario is that they actually cut the spigot off, to make fitting the guibo easier!

[sh55123]

Thank you Brian-I will closely examine the gearbox output flange when I disassemble things. Sounds quite a plausible reason for the vibration given that everything else is as it should be.

[sh55123]

So I have finally got to the root of the problem - the idiots who did the work for me have used a guibo from a different BMW ! I still have no idea where they got it from,but in short I bought a new Lemforder one from GSF and instantly realised that it was both thinner and (most importantly) had 10mm bolt holes, rather than the 12mm holes on the dodgy part my crap mechanics had used.

The larger bolt holes were of course preventing incorrect centering of the guibo, causing the vibration. Lemforder guibo = problem solved! (even with my original prop)

I have always been suspicious that the guibo the useless mechanics used had both a BMW and an SGF stamp on it, as we all know that genuine BMW parts cost an arm and a leg and I was charged ECP prices. Hey ho, learnt a valuable lesson-always do your own work unless you are incapable of doing it!

Thanks for your help on this Mr. Moooore

[BenHar]

Name and shame!

Ben