Noisy / whining gearbox

[mark10337]

Hi

I've noticed my gearbox is now starting to make some noise, especially when I go into neutral. If i depress the clutch, the noise goes away. It also makes similar noises when I take my foot off the accelerator.

I made a small video, and it also seems to be moving left to right a bit. This was driving about 2500-3000 RPM in 5th, and just taking the foot off the accelerator and back on again.

any thoughts are very welcome. Not sure if it is the mountings on the gearbox need tightening, the engine midmount adjusting and the clutch adjusting.

[PeterCrespin]

Is it part of the game to guess what type of gearbox?

[mark10337]

It's a Jag-T5 from Elite. I was thinking it is more of a problem with the clutch to gearbox / throw bearing from the noise.

[Barry]

Oh dear, not another Elite gearbox with problems on 5th. I have reported these not so long ago. I am on my second gearbox which is fine. New Forest Classics have had 5 problems relating to noisy 5th gears. They have also found too much play in the main shaft resulting in one instance with a crank shaft break. They were re-shimmed by Elite, but noisy gears seem to be still prevalent. How old is your gearbox?

[christopher storey]

I think we have been here before : I can conceive of no possible way in which end float on any gearbox shaft could result in crankshaft breakage

[mark10337]

Yes, the gear box is 8 months old, so still under warranty. Not something I really relish taking out and changing though. Dropping the whole engine out etc. Maybe in the winter.

The noise however that is concerning me, is how it acts in neutral. This is new. Also that it rocks from left to right. This seems to be getting worse. I will put it up on ramps tomorrow. Here is another clip at standing in neutral and pressing in the clutch. I'm not sure if the clutch play just needs adjusting. The whirring sound goes when the clutch is fully depressed.

[PeterCrespin]

I think we have been here before : I can conceive of no possible way in which end float on any gearbox shaft could result in crankshaft breakage

Have to agree with you, albeit sans evidence I'm ill-qualified to be too dogmatic. It appears to be in the same league as "Articulated lorry destroyed by head-on crash with dog."

No? Me neither.

At least we can be certain the noise cannot be the clutch release bearing.It happens cruising in fifth and stops when the clutch is depressed, which is exactly the opposite scenario.

The stabiliser is either correctly adjusted or not. Check, adjust if necessary, thrn eliminate from enquiries.

The Elite mount is two bobbins, rather like the 3.8 mount. If they are still good anex neither they nor the engine mounts have collapsed or come apart, the movement is what it is.
The noisy gears are something different, but with no foam or console, indirect fifth is bound to sound noisier than 1:1 4th gear. On my Getrag only 2nd and 4th were what I'd call 'refined' and idle noise was high. Heavier or synthetic lube may help but Elite must be allowed to specify their own grade if they are to offer warranty cover.

[Barry]

Irrespective of whether or not the Elite box caused a crank problem, New Forest Classic has experienced 5 boxes with excessive shaft float. This could be the problem with yours. Excessive movement of the box whilst running. The noise seems to be possibly bearings. Certainly that was the problem with mine. I hope you get a pro-active approach from the owner of Elite Racing to your problem. More information on NFC's problems with Elite, ring Daniel. 01590 610929

[mark10337]

Well, I've managed to locate at least some of the cause.

Had the car up on the lift today and I can see that some of the bolts securing the bell housing to the gear box have come out and others seem somewhat loose!

So that will explain the excessive movement and some of the new noises. Horrible job to fix this though. Not sure if I can drop and tilt the engine to get at it or it is a full out job

I'm thinking of taking the opportunity to just put back in the old gear box, and send back the gearbox for a replacement due to the excessive bearing noise, fluid leaking and crunch when it is put into 5th gear - unless I keep the clutch pressed for a longer period. Seems like something doesn't slow down fast enough to change the gear properly.

[PeterCrespin]

Well, I've managed to locate at least some of the cause.

Had the car up on the lift today and I can see that some of the bolts securing the bell housing to the gear box have come out and others seem somewhat loose!

Are you saying at least two of only four were missing? They hold the four corners of the T5 to the adapter plate. The adapter plate is then bolted to the Jag gearbox by the normal 8 bolts inside, which are tab-washered in pairs (or wired in the case of the clutch fork pair), and can't come undone. Plus you can't see them can you, as they are inside the bell obscured by the clutch? Which ones came loose and how come?

So that will explain the excessive movement and some of the new noises. Horrible job to fix this though. Not sure if I can drop and tilt the engine to get at it or it is a full out job

I'm thinking of taking the opportunity to just put back in the old gear box, and send back the gearbox for a replacement due to the excessive bearing noise, fluid leaking and crunch when it is put into 5th gear - unless I keep the clutch pressed for a longer period. Seems like something doesn't slow down fast enough to change the gear properly.

The crunch sounds like a dragging clutch. If I were a gearbox supplier asked to repair a box under warranty that had been run grossly loose and therefore side-loading the input shaft and cluster, I would either refuse or ask for a contribution, unless I had screwed up the assembly/installation myself. I would ask the installer to give you a freebie R&R. If it used to be OK, came loose and subsequently got noisy, you're relying on charity/goodwill for help. Good luck.

[nefematic]

What does R&R mean/stand for, please?

[Gfhug]

R&R:
Re-arm and re-fuel
Rest and recreation

[abowie]

What does R&R mean/stand for, please?

In this situation "Remove and Replace".

Given that the engine and gearbox have to come out to fix the problem, lots of work.

We usually bill 20 hours labour for this.

[mark10337]

It is the bolts from the bell housing to the gearbox adaptor plate, held by the tab-washers that have come lose. There is a hole at the bottom of the bell housing, and looking you can see. Currently there is one bolt with the tab washer hanging down where its pair has come out. I remember at the time, the original bolts wouldn't go into the adaptor plate as the thread seemed different. So some metric bolts with a torx head were used instead.

The crunch into 5th was always there since day 1, even with the gearbox mated up tightly and no play.

[PeterCrespin]

It is the bolts from the bell housing to the gearbox adaptor plate, held by the tab-washers that have come lose.....Currently there is one bolt with the tab washer hanging down where its pair has come out. I remember at the time, the original bolts wouldn't go into the adaptor plate as the thread seemed different. So some metric bolts with a torx head were used instead.

Perhaps I'm missing something here.

AFAIK Torx fasteners, male or female head, bolt or screw, have round faces where they clamp the component and the tab washers would be unusable. How did you clamp tab washers to Torx bolts? Tab washers are for hex-head fasteners and Torx-style hex head sounds a bit like an oxymoron. Besides which, you can't use a tab washer on the ones near the clutch fork pivot, so how did you secure those two? You can lockwire round headed Allen bolts but Torx are more difficult.

Assuming the adaptor plate is alloy, you wouldn't really expect to use the original bolts as they are fine thread for a hard ferrous application. Structural fasteners in alloy are almost invariably coarse thread. I'd expect metric for a product made today, but then I'd also expect to be given any special fasteners with the box. I guess there were none in the conversion kit, or did you just buy a bare box?

Still, whatever the thread, the loosening is the issue and I can't visualize how you secured them. A photo would be handy. You don't want a repeat...

Pete

[christopher storey]

There is absolutely no alternative but to remove the engine and gearbox and start again . It sounds as though someone has forced metric fasteners into what are imperial tappings, and thus the results were predictable, along with Peter's observations about the impossibility of tabbing a circular headed fastening. This appears, I'm sorry to say, to be what the Americans refer to as shade tree mechanic stuff with a vengeance, and I do hope the next attempt will have a better outcome - without wishing to be too gloomy you may be lucky and be able to reuse the gearbox casing after retapping the affected threads, but otherwise a rebuild in a new casing will be needed