question CVRT centrifugal clutch smoking!

I had a bit of smoke coming out of the engine louvers today while doing a bit of shuffling about on the drive.

It appears to only happen while doing any lowspeed steering maneuvers or neutral turns.

I found that the clutch drum was very hot and there are some signs of oil spray around the front bay, in line with the clutch.

I am assuming that the gearbox input shaft oil seal is leaking and oil is getting onto the clutch lining and burning off when doing a lot of low speed maneuvers.

This is what the clutch looks like from the outside and I think it shows some oil streaks.

Does an oilseal leak on the gearbox input shaft cause this sort of symptom?

Not an expert on these matters but I believe your assumption to be correct.

I also believe there are two oil seals which may need replacing (or to be more accurate if one is U/S then the other is also likely to be on its way) and you will need new clutch linings.

Diana

I had a bit of smoke coming out of the engine louvers today while doing a bit of shuffling about on the drive.

 

It appears to only happen while doing any lowspeed steering maneuvers or neutral turns.

 

I found that the clutch drum was very hot and there are some signs of oil spray around the front bay, in line with the clutch.

 

I am assuming that the gearbox input shaft oil seal is leaking and oil is getting onto the clutch lining and burning off when doing a lot of low speed maneuvers.

 

This is what the clutch looks like from the outside and I think it shows some oil streaks.

 

[ATTACH=CONFIG]92052[/ATTACH]

 

Does an oilseal leak on the gearbox input shaft cause this sort of symptom?

Sounds about right. If the seals are shot the clutch pads will be contaminated and would normally be replaced while you have the clutch apart for the seals. If the pads are not too bad you may be able to get away without changing them. Another tip on clutch wear. When a new clutch is fitted new a C clip was also fitted. This C clip joined both ends of the gater spring to allow for some adjustment once the clutch started slipping i.e. if the C clip is fitted it could be removed once you notice clutch slip which will then give you additional life on the same clutch.

Hi,

I have this problem with my TN15 gearbox also, did you manage to find a source of new seals.

The Part numbers are NSN 5330-99-363-9724 or FV792970

PM me if you have some spare.

Regards Peter

Try Chris G on this Forum, he may be able to source them or a suitable replacement.

(Please note that I have no connection with his business but happily consume his wife's fine home made cake at shows)

Having investigated there are a number of problems with the gearbox, which are self inflicted.

Don't start off in 3rd gear! use 1st. Starting in 3rd causes clutch wear. and brake band wear on the 3rd gear brake band.

I eventually found the change up and down speed off instructors notes for a PETROL engine.

Change up is 2000 RPM and down is 500RPM - but of course watching the tacho is another matter!

Diana

Sounds about right. If the seals are shot the clutch pads will be contaminated and would normally be replaced while you have the clutch apart for the seals. If the pads are not too bad you may be able to get away without changing them. Another tip on clutch wear. When a new clutch is fitted new a C clip was also fitted. This C clip joined both ends of the gater spring to allow for some adjustment once the clutch started slipping i.e. if the C clip is fitted it could be removed once you notice clutch slip which will then give you additional life on the same clutch.

 

Change up is 2000 RPM and down is 500RPM - but of course watching the tacho is another matter!

 

Diana

Good luck keeping to those figures in a real life road situation! Although designed for "hot shifting", it may be beneficial to clutch and gearbox life to come of the throttle between up-changes (I practice this). I find I can keep an eye on the tacho by glancing at it (but then I am a shortie). Easier to see than the speedo.

Vince only quoting from training notes...

Diana

Good luck keeping to those figures in a real life road situation! Although designed for "hot shifting", it may be beneficial to clutch and gearbox life to come of the throttle between up-changes (I practice this). I find I can keep an eye on the tacho by glancing at it (but then I am a shortie). Easier to see than the speedo.

It seems like you would want to add length once things were worn rather than remove it, I don't suppose you have the page that shows the clip and use of it, a part # would be nice as well?

The x-mod has clutch linings, springs, as well as seals both quite cheaply of late so if one has gone through the effort of removing the clutch one might as well as replace the linings and springs.

https://www.thexmod.com/item_detail.asp?id=452&t=Liner_Clutch_FV659124_

Sounds about right. If the seals are shot the clutch pads will be contaminated and would normally be replaced while you have the clutch apart for the seals. If the pads are not too bad you may be able to get away without changing them. Another tip on clutch wear. When a new clutch is fitted new a C clip was also fitted. This C clip joined both ends of the gater spring to allow for some adjustment once the clutch started slipping i.e. if the C clip is fitted it could be removed once you notice clutch slip which will then give you additional life on the same clutch.

Teletext, you may be right. Just reading my own post and wondered why I put it down that way. It's been a long time since I played on centrifugal clutches but then again once the springs loose some of their ability to close due to use taking the c clip out would ensure they were not too loose and that the pads would disengage from the drum at low engine speed.