Transmission 'clunk' and whine

[Bellissimmo]

Help!

My new Roadsport (370 miles) 'clunks' sometimes when changing gear. It doesn't seem to happen when the drive-train is 'under load' but it does every time I do what might be termed a 'sloppy' change. So it's very noticeable when I'm in traffic and hunting for the right gear/rev combination (I'm still learning!). I had the car up on axle stands with the engine running and I can reproduce the noise by putting the car in first gear at tickover and disengaging/engaging the clutch. Also during this session, I discovered the gearbox was hot to the touch (after about 40 mile drive).

 

Opinions please on:

Should the 'box get that hot?

Is 'The Clunk' a problem with my driving; a setup/mechanical issue or TADTS?

Where should I look?

 

Any help gratefully recieved.

 

Steve

 

Edited by - bellissimmo on 6 Oct 2008 12:51:10

[I.Mupferit]

Is it fitted with an LSD? They can be particularly clunky. You must bear in mind also, that you are sitting very close to the gearbox, prop shaft and differential, with very little, if any, sound deadening between you and these components. You will hear any and every noise they are making. You soon get used to it.

 

Edited by - Brent Chiswick on 1 Sep 2008 13:47:47

[ashaughnessy]

Possibly worth checking the bolts connecting propeller shaft to differential??? I once had a similar clunk that went away when I tightened said bolts on my live axle car (some of them weren't as tight as they should have been).

Anthony

[Bellissimmo]

Brent,

 

It's a standard diff.

 

... and I'm starting to get the message about being involved in the whole driving experience but this one in particular is worring me.

 

Steve

[I.Mupferit]

Try getting someone who has owned a 7 for a while to drive/ride in the car and see what their opinion is. It can be a bit of an agricultural experience at times if you aren't used to 7's but as I said, you soon get used to it and learn to ignore these noises.

[akakubi]

Steve,

 

Mine clunks audibly on upshifts (I do have an LSD though). The gearbox is precise, but not what I'd call silent. It has a feeling of a (old) rifle bolt being slotted in. And the gearbox also gets quite warm after some miles.

[Bellissimmo]

Thanks to all for suggestions and advice.

 

I took the car back to the factory yesterday and it turns out that there is an issue with the current batch of diffs whining. To alleviate the whine, Caterham have 'backed off the pre-load' (or grimbled the mangel spline ). Anyway, the upshot is that they've reduced the whine and exchanged it for a clunk.

 

So, reassured that the propshaft isn't going to drop out and pole-vault me into oncoming traffic, I'm off out for a blat 😬 😬 😬

 

Steve

 

PS ...and mybe take a look at a Quaiffe

[Bellissimmo]

I took my car in for its first service on Saturday and, apparently, Caterham have solved the whine/clunk problem that has affected a number of recent builds (I wonder how many others are having problems??). They are planning to replace my diff as part of the 1st service so the whine (which has been getting worse) and the clunk (which I've learned to live with) should be gone when I pick it up next Saturday.

 

If there's anyone else interested, I'll post an update next weekend.

 

Steve

 

 

[timbo]

 

all sounds very normal to me in the BEC 😬

 

BUSA POWWWER

[neilg]

Yeah Timbo that's right i have a feast of clunks to worry about in the blackbird!! Is it the gearbox, or the reverser box or is it the diff......er er. NVH tests, i don't think so 😬

[Bellissimmo]

... so, if I'm suffering all the noises of a BEC, I may as well switch loyalties and take advantage of the attendant fun then???

 

Hmmm, ISTR 30k worth of BEC sitting around doing nothing...

 

Edited by - Bellissimmo on 6 Oct 2008 17:25:59

[Mickrick]

I thought that was all part of the Seven experience.

My factory built R300 was all clunk and wine, but it got better as I got better/used to the car.

[The Rookies]

Steve

 

I'd be interested to hear of your update one you've got the car back and also what remedies Caterham undertook. Having taken my first run out in my new 150SV last week it was whining and clunking much more than i expected. Whilst this might be normal to an extent it did seem excessive.

 

Seems like a few people have this problem on recent builds?

 

Jonathan

 

 

[Bellissimmo]

Jonathan

 

I'll try to update Saturday pm. My whine has definitely got worse over the past 1000 miles and the clunk has 'improved'. My (laymans) thinking is that there is something 'not right' inside the diff because it sounds to me as if the 'gears' are grating together rather than meshing cleanly. I can only assume this will get worse as the gears wear until either something breaks or they wear themselves into a shape that 'fits'.

The clunk is something that you can improve with a change to driving style. I find that if I 'drive it like I nicked it' there's no clunk. If I'm driving more sedately, I get a clunk on most changes and sometimes if I let off the power and then put power back on there's a clunk. This is indicative of some play in the drive train and seems to align with what Caterham told me (i.e they have backed off the pre-load).

Please excuse my non-engineering approach to all this - I have a theoretical understanding of how stuff works but no real experience of what might be wrong or, indeed, what a Seven normally sounds like.

 

Steve

 

Edited to add: It would be nice to see a Technical Update from Caterham on this. I know directly of one other who has this issue and he indicated (as you have) that there are others

 

Edited by - Bellissimmo on 8 Oct 2008 11:57:08

[The Rookies]

Thanks Steve, will be interested to hear what the difference is!

 

You non-engineering approach suits me just fine - like you this is my first time at building/driving a 7 so its a lot harder to know what sounds are normal. I find that the whine is worst when on the overrun in higher gears - 3rd, 4th and 5th in my case - although it is fitted with an LSD which i understand are generally noisier than standard. Clunking, like you say, can be eased by driving style but is hard to avoid at slow, relaxed speed!

 

Jonathan

[Bellissimmo]

Jonathan,

 

If you have a LSD that's (apparently) a whole new ballgame. If I understand correctly from other threads it is more in the nature of LSDs to whine and clunk. But, as you say it's hard to know what's 'right'. There's no soundproofing and you're sitting next to the damn thing so I guess it's way outside any recognised norms even for a sports saloon. All I know is that my diff was a bit noisy at 300 miles and now (at 1500) it sounds like someone trying to drill through a brick with an electric screwdriver. Likewise, it's worse on the overrun and when maintaining a constant speed after overrun has 'finished' (if that makes sense )

 

Update Saturday...

 

 

[myothercarsa2cv]

Steve, give me a shout and I'll take you out in mine sometime so you can compare the noises. Mine whines, clunks shouts all it likes, I'm pretty used to it after 4500miles (since July 😬 )

 

It's also a new diff, so I'd be interested if mine is fubar'd too, diff would need to come out to do the rear g'box seal, so would be a good money saving wheeze if I can get it on warranty 😬

 

Mine stops whining on overrun though, and goes cugclocugclocughfhgeb instead. After 65mph the whining fades, and although the clunking on changes (backlash) disappears when pushing on, I suspect this is more because the noise of the engine and exhaust drowns it out than anything else.

 

John

_________________________

 

Bugsy: '82 2cv6 (Hitting it fixed it )

Talloulah: '08 1.6K Classic (Tarnishing nicely ☹️)

[Bellissimmo]

John,

 

Thanks for the offer - which I'll definitely take you up on! Wish we'd swapped for a while on the last blat so we could compare notes. Hoping mine'll be better on Saturday but you're always welcome to give it a try.

[vipdesilva]

Will be very interested to hear if the new diff makes a difference Steve. As I've mentioned to you, mine makes a hell of a lot of noise and I've been waiting to hear that Caterham have a solution. And yes, there are a few of us in the same boat.

 

Time to ring customer service again I think

 

Vip

 

Build Pics: here

[TheManAlive]

I'm another one in the same boat. was told that they would contact me when they had a solution so the diff could be replaced. i too will be calling tomorrow!!

 

 

[Beverlonian]

Hi,

 

who received their kits when? Just trying to work out how wide spread the problem might be. I won't have much warranty left when I get to drive it so it would be good to know if I have to do a lot of miles quickly 😬 to find out.

 

Andy

 

PLOD's been, waiting for DVLA again!!

[TobyCoulson]

Having just had a Quaiffe diff fitted by CC the whine is more audible under load but less so when backing off. Over a certain speed or rev range it goes away completely

[Bellissimmo]

Mine arrived on 18th April.

 

I've only been in two other Sevens recently - the Caterham (Surrey) demonstrator (Sigma Roadsport SV) and a Blat to Goodwood with SM25T (K-Series Roadsport SV IIRC) - and neither of them were anywhere near as noisy as mine is. The ride in Ian's was certainly brisk and had it's fair share of road/engine/wind noise but it was still easily possible to have a conversation. In mine, conversation is rapidly going out of the window

Noise tends to be very subjective at the best of times and especially so for me as I'm deaf to certain ranges which makes me oblivious to some tones and sensitive to others. All I can say is that from my maiden voyage, mine was much noisier than I expected it to be and that by 300 miles it was noisy enough for me to take it in to Caterham Dartford for a check-over - with visions of something having come loose or me having installed it incorrectly. It had slightly over 1500 miles on it last Saturday when it went in for its 1000 mile service and was well into being uncomfortable-to-deafening - certainly loud enough to inhibit conversation.

 

adcatman - I hope you get your paperwork through soon enough to get 3-400 miles on before your warranty expires 🙆🏻

Vip, TheManAlive - It's up to you, but I would suggest you wait til Monday by which time, I'll have reported back on whether they actually do have a fix.

 

Steve

 

 

 

 

[The Rookies]

Mine arrive on 2 June and has about 400miles on it so far. Only been in one other caterham (98 K series with LSD) which was nowhere near as noisy.

Jonathan

 

[TheManAlive]

when it went in for its 1000 mile service

 

Er...slightly off topic I know but have I missed something here. i had my 500 mile service done, and was then told to bring it back at 6000. I had a look at the handbook and it confirms every 6000. Is this wrong?

 

As for delivery dates, mine was in April. BUT the first dif I had leaked, so I had to strip it out and then picked up another in early may from Caterham showroom. thats the one that has been noisy.