Gearbox suddenly become noisy

[Nick Whitehead]

Help please. Am I missing something stupid?

My Vitesse 2L Mk2 gearbox has suddenly become noisy in all four forward gears. The car had been laid up for 20 odd years but I recently put it back on the road with a new clutch, housing and release bearing.

I have driven it satisfactorily for about 30 odd miles, just locally road testing various replaced brake bits (and the clutch) etc. Sounded great, considering its age.

I disconnected the drive shaft to jack up the gearbox (block of wood under the sump) to replace the rear gearbox mounting bushes. Reconnected the drive shaft (matching the holes as before between gearbox and driveshaft).

Went for a road test and experienced very noisy transmission noise.

I disconnected the drive shaft again and started the engine, went through the gears with no load on the gearbox; it seemed quieter, but I'm not certain?

Has my gearbox suddenly failed somehow? I'm more used to a gradual degradation with gearboxes (but it's been a while since I did this sort of thing...)

Anything obvious I'm missing? And what's my next move in diagnosing my problem? (I could try posting a sound file..)

Thanks in advance for your wisdom.

Nick

 

 

[johny]

Obviously the gearbox oil level is correct? Its possible something has failed in the gearbox but seems a bit of a coincidence so first suspect the work that has been done: Recheck that nothing is now in contact with the gearbox and that its free to move on its new mountings. Everything is tightened up still. Then theres the new clutch which is obviously more difficult to check but could something have come loose?

You say noise in 4 forward gears so does that mean it doesnt do it in reverse?

[DanMi]

sounds to me like the new mounts are allowing the prop or gearbox flange to rub somewhere

[Pete Lewis]

yes look for some contact since upsetting the mounts like prop shaft contact with tunnel and handbrake cables etc

including the exhaust fouling chassis 

Pete

 

[Nick Whitehead]

That’s what I thought initially. But I can’t see where, and it’s doesn't sound to me like that sort of noise. But on your suggestion I will double check. Thanks. Nick

[johny]

But then youd think running it with the prop disconnected, as Nick has done, would make a big difference?

[NonMember]

Just to eliminate the stupid...  you first noticed the noise on road-testing after disconnecting the prop. This means you'd taken the cover off. Had you put the cover back on before the road test? Gearboxes are horrendously noisy without the sound-deadening cover in place. Otherwise I'm with Pete - what you did shouldn't have affected the gearbox itself but could have left some unwanted contact point.

[Nick Whitehead]

32 minutes ago, johny said:

Obviously the gearbox oil level is correct? Its possible something has failed in the gearbox but seems a bit of a coincidence so first suspect the work that has been done: Recheck that nothing is now in contact with the gearbox and that its free to move on its new mountings. Everything is tightened up still. Then theres the new clutch which is obviously more difficult to check but could something have come loose?

You say noise in 4 forward gears so does that mean it doesnt do it in reverse?

I will check the oil. I had drained and replaced it. Maybe a massive leak? No sign of oil on the garage floor though….

ill have a good look for fouling around the gearbox.

hope it’s not the new clutch….

NicK

[Pete Lewis]

dont forget the prop UJ 

always question the last job  its often the culprit 

Pete

[Nick Whitehead]

1 minute ago, NonMember said:

Just to eliminate the stupid...  you first noticed the noise on road-testing after disconnecting the prop. This means you'd taken the cover off. Had you put the cover back on before the road test? Gearboxes are horrendously noisy without the sound-deadening cover in place. Otherwise I'm with Pete - what you did shouldn't have affected the gearbox itself but could have left some unwanted contact point.

Thanks. Road tested with the cover on and off. I’ll keep checking for unwanted touch point. Nick

[Nick Whitehead]

2 minutes ago, Pete Lewis said:

dont forget the prop UJ 

always question the last job  its often the culprit 

Pete

Prop UJ. That’s a thought! When I let the gearbox down after changing the bushes it fouled the disconnected prop shaft UJ. Perhaps I’ve damaged it? Next thing to check. After the oil….. nick

[Pete Lewis]

on road test or on a jack test  note when and how the noise presents 

is it immeadiate..constant    all gears   some gears  accelerating  decelerating 

under load   on coast     all the time 

etc

Pete

edit  on the coupling it is most important the faces and the location spigot flange are not damaged from maybe earlier work

any bruising byba gorilla on the faces gives you runout 

and really  marking props to return to where they came from is incorrect the faces and spigot control the concentricity  not getting the same bolt holes aligned    what do you think happed on the assy line ???  

(mark and position as was is fine but should be unnecessary

)if repositioning gives a problem there is a problem glaring about  the coupling runouts

Pete

 

[Colin Lindsay]

If I've read this correctly - gearbox fine until you disconnected the prop to replace the rear bushes, on replacement of the prop it's noisy, remove the prop again, it's quieter? Seems to point more towards the propshaft then, especially if it's in all the gears. Something's been disturbed by the removal / replacement; check the ujs, see if anything's hitting - watch for shiny metal witness marks - and don't eliminate the diff end as it too was disturbed when the prop was moved.

[Wagger]

Did I read that you changed the oil? Check that what you put in is the same type as you drained out, Also, check that the mounts are not harder than the old ones. The metal bits inside could be hitting one another.

[Nick Whitehead]

45 minutes ago, johny said:

Obviously the gearbox oil level is correct? Its possible something has failed in the gearbox but seems a bit of a coincidence so first suspect the work that has been done: Recheck that nothing is now in contact with the gearbox and that its free to move on its new mountings. Everything is tightened up still. Then theres the new clutch which is obviously more difficult to check but could something have come loose?

You say noise in 4 forward gears so does that mean it doesnt do it in reverse?

 

37 minutes ago, Pete Lewis said:

on road test or on a jack test  note when and how the noise presents 

is it immeadiate..constant    all gears   some gears  accelerating  decelerating 

under load   on coast     all the time 

etc

Pete

 

I will do a proper test and report back on these points. Thanks Nick

[Nick Whitehead]

8 minutes ago, Mathew said:

What oil? Did you put in? Ep90 gl4 spec?

EP90. That's right? Nick

[Wagger]

Can you describe the noise? Is it a constant whine, knocking or scraping sound? My Vitesse sounds like somebody exhaling constantly when running in neutral. Driving gives a constant whine in all gears, but I have no sound-proofing under the plastic cover. (Next Job),

Check that you have not distorted the propshaft flange when the gearbox clouted it. And the one on the gearbox. That would cause clonking if bad, and vibration at about 45mph if only slightly damaged.

 

[steveo]

I think I have the same problem on my Herald, put new gearbox mounts on it a few weeks ago, had to undo the prop but marked it, now have a strange rotation noise from under the car, only with the power on, freewheeling its ok.

Didn't drive it before as it wasn't roadworthy, but the wife thinks it was ok when she drove it home when we first got it. 

Will try & get under it & have a look in the next few days.

[Nick Whitehead]

Update. Gearbox has oil in it!

Have jacked up the car and tested it in all four gears + reverse. Got under the car this time to do a visual inspection while the prop was turning. Noise is coming from the prop shaft. I can't see that its fouling the body anywhere, so I'm suspecting UJ.s

I will ensure they are fully greased up, but is there anything else I should be looking at?

When I had the gearbox out to change the clutch I managed to loose my marks to match up the flange on the gearbox to the flange on the prop in the same place it had come off.  So it went back randomly. But had been running fine for 30 miles or so. Prop seemed balanced.

When I replaced the gearbox mounting bushes, the prop went back in the same place as it had been before.

Still, could I have an un-balanced prop shaft? Would that make a lot of noise? How can I balance the prop shaft? is that a job for the garage? or DIY?

Thanks again for all your advice

Nick

[steveo]

Just been under the beast, exhaust clamp was close to the the chassis & the sound proofing stuff was rubbing the prop, done all that & went for a quick drive and its still the same ! more like something is loose / vibrating type of noise, uj's look ok, need to get it up on my ramps.

Still that's two things ruled out, and its better to be under the Herald than watching the telly ! 

[johny]

Out of balance prop doesnt cause much noise but vibration through vehicle usually at about 50 mph and over...

[Pete Lewis]

best way to check a UJ  if you stick a pry bar in the cross head of the UJ and lever the yoke  you dont want any lift or float 

and on Vitesse and GT6 the telescop can wear dreadfully and give a lot of wobble 

I take it this is a std 3 rail geabox  no overdrive ???

gearboxes dont normally make noise in all gears unless the input shaft has lost some teeth and thats quite a disaster noise 

 

Pete

 

[Nick Whitehead]

So. Issue resolved. I think the new replaced bushes for the rear of the gearbox were not seated properly in their groves on the chassis cross member. Meaning the gear box and the prop shaft were not in complete alignment as they were before replacement.

Thanks again everyone for suggestions.

Nick

 

[Pete Lewis]

pleased its sorted and ...like cheap fixes  its easy to open the wallet and get nowhere

Pete

 

[steveo]

Sorted the strange noise, got her up on ramps at the weekend & the rattle seemed to come from the prop shaft, took the rear uj assembly off & the uj was tight, pumped it full of oil to clean it out then filled it with grease ( will need replacing at a later date ) 

The noise was coming from the bit that slides in to the prop, cleaned it up & packed it with grease, just done a 15 mile trip & no noise !

Even better news is the oil leak from the front crank seal has almost stopped ( but did find the diff is leaking on every seal when it was on the ramps )

Car drives really well, today is longest trip so far, runs perfect, got up to 60 mph in places, its fun to drive & good performance from a 54 year old 1300cc.

Cheers, Steve.