Horrible noise from drivetrain

[Kevin Atkins]

Hi all, I can appreciate this might be impossible to offer guidance on, but I've started getting a very nasty tinkling / metallic scraping sound from what I think is the nearside rear axle but I can't be certain; it could also be coming from the propshaft. This seems to happen when applying power, it quietens right down on the overrun. Needless to say, I've decided not to risk driving the car further until I sort out what's going on..

I've popped the rear nearside wheel off and haven't been able to detect anything untoward. I did replace the half-shaft UJ on the offside; the nearside one seemed fine with no discernable play in it. One point to note is that very early in my ownership, I suffered a flat tyre on the nearside rear during moving the car and the tinkling noise under that condition was exactly the same with the tyre flat but disappeared once the tyre was inflated to the correct pressure - odd, I know, but maybe it was something to do with the angle of the half-shaft?

I'm wondering whether maybe the diff half-shaft output bearing on the nearside has broken up perhaps? If anyone has experienced similar I'd be interested to know what it might be, but understand it's a difficult one to diagnose remotely!

[Pete Lewis]

in general  bearings grumble  UJs click

 

tinkling and scraping  have you pulled a drum off and checked for lining or spring adrift 

Pete

 

[johny]

Yes and do one thing at a time including check diff oil level and grease wheel bearing, checking for changes in the noise each time...

[Pete Lewis]

and never forget   loose wheel nuts or a problem in that zone 

even the drum holding screw is not in contact with the wheel nave 

pete

[Kevin Atkins]

Thanks for the pointers - I'll go through each and see what happens.. Rear hubs / wheel bearings could be a good call - I haven't greased them, and goodness knows when they were last done.. I'm assuming it's just the grease nipple on the bottom of the hub / trunnion? Also, I've added a bit of extra ballast in the rear to get the new spring to sit better / settle - two bags of builders' sand and two big bags of compost, so there's some weight in there, that might be an aggravating factor, or exposed the issue

[Pete Lewis]

unless someone has added agrease nipple there is ahex headed plug screwed into the back of the trunion bearing housing  

the recommended is 4 pumps on the gun annually  dont over do it  as excess should escape via the drive shaft seal and a drain into a catcher in the back plate 

Pete 

[Kevin Atkins]

Today's update.. my brother-in-law and I have been through the rear end of the car - we checked inside brake drums / brake components, shoes springs etc, all OK; we greased the rear hubs - thankfully someone had previously fitted grease nipples; checked security of all bolts and fixings - there did appear to be some play in the lower trunnion bush thing on the nearside - the steel tube with rubber bushes forming the lower pivot - but that wouldn't explain the noise. I test drove the car and the noise is the same.. and - a  good-spirited motorist behind me tooted and pointed at the nearside of the car and flashed his hazards. So something is clearly very badly amiss, and must be visible as I drive. I limped home, very slowly.. I clearly need to get this fixed as it looks like a serious safety issue now.

The only thing I can postulate - might the nearside half shaft be broken, which might cause the hub to whip around / vibrate, visible to others - there is a nasty vibration coming through now at 35+ mph? But if it was completely broken, surely I'd lose all drive as the diff would just spin the broken shaft?

[Colin Lindsay]

Chock the front wheels VERY SECURELY, jack the rear of the car up VERY SECURELY by something other than the rear axles, start the engine and put it in gear. That will enable you to see what's amiss. Make sure it can't move or roll off either the jacks or the chocks. If following drivers can see it, it's bad. You're correct in that you wouldn't have any drive with a broken axle. Look for witness marks on the rear axles, are they rubbing off the chassis? Maybe the following driver saw sparks?

 

[johny]

yes a completely sheared half shaft will cause a non rotaflex suspension to colapse on that side so thats impossible in this case. Apart from sparks or smoke the only other thing I can think a driver following you might see is a buckled wheel... 

The problem with powering the back wheels while jacked up as Colin suggests is that the half shafts will hang down a lot and not run in their normal position. Better would be someone following you in another car to see the same as that motorist saw but I wonder if it isnt already too dangerous for that😲

[Pete Lewis]

if it is visible to a following car then it is likley to be a bent drive shaft giving you wheel wobble

or a tyre has broken its radial band and whilst looks ok standing goes completely out of shape when driving 

a good look at the rear end by driving past  a viewer should give you a clue 

running on a jack wont show up a tyre failure but would show a bent shaft 

Pete

[Kevin Atkins]

Thanks for the replies folks. I've had a look at the nearside driveshaft and on closer inspection, there does seem to be a bit of a witness mark which suggests contact with the chassis rail - one half of the driveshaft has clear evidence of 'polishing' / fresh metal so I think you may be onto something with that. Thing is, earlier we rotated the wheel by hand and couldn't see any real evidence of it being out of true, but that was with the suspension unloaded. I'm wondering whether before, when I had the old spring in and the suspension was sitting far too low and negative camber on the rear wheels, maybe the 'set point' was such that the drive shaft was further away from the chassis rail but now it's much closer.

Looks like I'm in for replacing driveshafts at a minimum, and possibly doing the hubs at the same time - I believe the rear hubs are a bit of a pig of a job and require the correct tool? And while I'm at it, maybe the diff output shaft bearings / seals.. oh, joy - this is turning into a much bigger job than first anticipated!

[Pete Lewis]

most shafts will contact the chassis when jacked  and on full droop

that will mark up the shaft 

and its not that the guy behind you was seeing     its more obvious  so you have to get followed or similar to see what he was flashing you for 

its not a shaft rub its something far more obvious   

Pete

[Josef]

You do need the correct hub puller to do the rear bearings etc yes. There’s got to be someone local-ish to you who can lend you one though. A press is handy too, or some adaptor that allows the hub puller to also push the drive shaft out of the bearing. I’ve done that bit by the ‘smack the driveshaft on scrap wood till it moves’ method and I do not recommend it!

[Kevin Atkins]

Thanks Pete, I'll see if I can get a mate to follow me a short distance at low speed and we'll see what that turns up - like you say it's got to be pretty obvious if another motorist has seen it..

Going to be a bit pushed tomorrow but will see if I can get on it. will post back what we find

[Kevin Atkins]

3 minutes ago, Josef said:

You do need the correct hub puller to do the rear bearings etc yes. There’s got to be someone local-ish to you who can lend you one though. A press is handy too, or some adaptor that allows the hub puller to also push the drive shaft out of the bearing. I’ve done that bit by the ‘smack the driveshaft on scrap wood till it moves’ method and I do not recommend it!

OK thanks for the heads up on that - I think a short test drive with mate behind, then figure out what to do next.. As will probably be reasonably clear from this and some of my previous threads, I'm er, not exactly a time-served motor mechanic so this little car has been something of a baptism by fire so far! But it's got to be worth it in the end I'm hoping.. still such pretty cars after all these years

[Dick Twitchen]

May have missed something but you do not have wire wheels fitted by any chance?

Dick

[mark powell]

That could be a good shout!  Loose spokes would jingle and wheel would wobble.  Why didn't I think of that possibility?

[Colin Lindsay]

11 hours ago, Pete Lewis said:

most shafts will contact the chassis when jacked  and on full droop

Some do but depends on the suspension setup. I could do that procedure on the MK1 GT6 and with the Herald on the ramp can rotate the rear wheels with no chassis contact. Just let the clutch out very gently!

[Kevin Atkins]

1 hour ago, Dick Twitchen said:

May have missed something but you do not have wire wheels fitted by any chance?

Dick

Morning Dick,no she's got standard Mk. 3 steels fitted, although the wheels are a bit grotty. I'll post back here with what I find from further checks / inspection, although that's unlikely to be this weekend now.

[Wagger]

Double check that a circlp has not popped out of the U/J. It could 'Oscillate' in and out. However, that usually causes catastrophic falure as the needle roller cup pops right out. A bruised yoke can stop it though.

Check for a 'Bendy' wheel too.

[Pete Lewis]

i would still plump for a tyre band failure  as thats very obvious to anyone  following

but tends to be invisible to a static viewing   in  that it just looks black and round till you apply any rotation or torque 

then all hell breaks loose with the tyre flapping and wobbling all over the place 

Pete

[Stratton Jimmer]

I had a tyre band failure on my old Land Rover Series 2A and the description given for this fault matches exactly what I had. My boss was driving behind me and flashed me to pull over. He pointed it out as it was plainly visible from behind while all I had was the noise and imbalance.

[Kevin Atkins]

Update.. I decided I didn't really want to risk driving the car in its present state, even if only for a short distance with someone following me.. So I haven't bottomed out the possibility of it being tyres, but the tyres on it are virtually brand new - could still be faulty, but I've decided I need to bite the bullet and sort this thing properly. It's very much an unknown quantity at the moment, 50 years old with secrets / wear etc..

So... Given that the diff must have been running virtually dry of oil for I don't know how long (I had to put nearly half a litre in...), and the whole backend being tired anyway, I've got a diff rebuild in progress with Mike Papworth, got new driveshafts, hub bearings, trunnion bushes (the current ones are completely shot on the N/S - that might have been part of the problem!)..  the whole lot - I'm rebuilding the whole thing, then I know what I'm working with.

At the same time (this has turned into a bigger rebuild than first anticipated...) - I've also plumped for a rebuilt O/D gearbox from Mike Papworth.. current box is noisy, non O/D, and having just got a Heritage Certificate for the car, it was originally supplied with O/D so I'm kind of returning it to its original spec..

It'll be lovely when it's done, and I'll know that virtually all the running gear is new or near new.. 🙂

[Pete Lewis]

thats a plan  let us know how it works out      and give the wallet a rest  Ha 

Mike is one of the best im sure all will be good 

Pete

[Puglet1]

Kev Atkinson. What driveshafts did you get?

Pete