Propshaft UJs

[Raider]

On a test run today in my early MK2 2000 I started to notice a new noise develop on acceleration which sounded like maybe a wheel bearing or perhaps the clutch release bearing. When I got back home though I didn't think too much about it and as I was getting out the car I picked up the new MOT certificate the car got this week.

On this was an advisory which caught my eye: "Front prop shaft joint excessive play". Hmmm. This could be the noise I had heard developing.

Looking back in my records though the car had a new front UJ in March last year which failed big time in October so I decided to replace the whole propshaft with a Chris Witor reconditioned one and now the front UJ is showing excessive wear? There's something not right here and the car has only done about 400 miles in a year!!

I have my suspicians and would like thoughts from others.

On Chris Witors site he says on engine mount packing plates he says

"© Chris Witor 2011
Front engine mounting options
When the Mk1 2000 was launched, there were no packing pieces under the engine mounts. The need for packing pieces was brought about by the long stroke 2.5 engine having a deeper sump. Packing pieces were added to allow the sump to clear the steering rack.
In 1971 Triumph engineers realised that the spacers had altered the propshaft
running angle, so the later diff bracket was applied at ME42722 2000 & MG21067 2.5 PI. From then on, the 2000 also used spacers under the engine mounts.

Now, my 2000 is a very early 1969 model, with a very low ME number so I think this means it should have no packing pieces.

The previous owner fitted a later 2000 engine and rear diff along with a j type overdrive which it didn't originally have. Checking under the bonnet there are engine mounting packing pieces fitted.

I suspect these packing pieces shouldn't be there and because they are they are causing the propshaft to run at an incorrect angle and putting too much stress on the front UJ.

Any thoughts out there?

[Nick Jones]

Propshaft UJs on the way out usually show up as clonks when taking up drive, extra driveline shunt, with clonks when moving slowly in traffic and speed related vibration.  400 miles should not kill a decent quality UJ even if the gearbox mount isn't hung quite right.

They don't make wheel bearing or clutch release bearing type noises so I'm doubtful the prop is your problem.

You seem to have one of those saloons that likes to test your patience......... I remember that......!

Nick

[Richard B]

But if the PO changed the Diff as well he might have changed the nose-piece to suit. I thought the change was to prevent driveline vibration?

You can measure the nose-piece with a ruler, its either 5/8" or 7/8" IIRC. Chris's props are nomally ok. May just be a faulty part.

Do you have a good propshaft place near you who could change the U/J & balance it? Down south I use Feltham Propshaft Services near Heathrow.


Re-reading yours and Nicks post, it does not sould like the U/J anyway, more like a bearing somewhere. Check the rear hubs for wear?

[beefertoo]

No the nosepiece was the one that came with the 'new' diff,i only remember this as I was going to change it over but couldn't get the old one off!

Not that it was something that I considered/knew about when I was swapping bits about, just thought it quaint that a manufacturer put such things as packing pieces under the engine mounts and suchlike.

Out of interest where is the 5/8  or  7/8  measurement taken from? My current pi has some vibrations to look into when I get time

Craig

[piman]

Hello Craig,

Here's a picture with the two different nose pieces.

Alec

[Raider]

IIRC?

I don't think those pictures will help me much :-/  I get the theory though. I need the right engine mounting packing pieces to go with the diff right nose piece.

But why should I have 2 UJs fail in a year? I think I may get the original propshaft fitted with a new UJ and balanced. Then I can keep swapping between propshafts until I get this particular problem sorted.

[Raider]

IIRC?

I don't think those pictures will help me much :-/  I get the theory though. I need the right engine mounting packing pieces to go with the diff right nose piece.

But why should I have 2 UJs fail in a year? I think I may get the original propshaft fitted with a new UJ and balanced. Then I can keep swapping between propshafts until I get this particular problem sorted.

[Richard B]

Raider wrote:

IIRC?

Sorry;

"If I Recall Correctly"




ps. thanks to the photo Alec posted. The measurement is from the bottom of the tube to the flat base of the nosepiece.

[esxefi]

you need to check that g/box and diff flanges are parallel with each other.

an axial misalignment is ok as long as it isn't too much but flanges that are not parallel will induce unwanted secondary oscillations as the ujs will fight each other in rotation.

here's a very nasal OU style video ::).....

https://www.youtube.com/watch?v=VD1PuGdVB5U

[Nick Moore]

Before you start pulling the car apart, get underneath and check that the MOT man actually knew what he was doing. History is replete with testers failing to recognise normal play in a component, or mis-identifying the bit they were wiggling.