Serious failure on track, Driveshaft, Diff or Box?

[Craig-S]

I cant seem to find anyone with similar symptom's so seeking some advice before deciding the best course of action. I have a track only 172cup and had what seems like quite a serious failure yesterday at Castle Combe. Its incredibly difficult to explain which is why im finding it hard to search for answers, so maybe someone will know exactly what I mean right away. I drove the car pretty hard on Semi slick's, and after about half a day on a fast right hander at full throttle I got an almighty cluck and grinding noise. Car lost all drive until I straightened up,where it picked back up again.

I limped back to the paddock and put the car on stands, to find nothing obvious other than a lot of movement in the engine on its rubber mounts. On stands,running in gear it was fine in a straight line, but on full lock it would almost jump off the stands.

Decided to do another session in it, and all was well on about 75% ability, but once pushed again it instantly failed, this time worse. I nursed it back in,but any slight load would see the car lurch and dive, loose drive and slow. The only way I can describe the noise and feeling is like if the engine had dropped and was dragging along the floor.

I'm pretty mechanically minded and have built cars / engines / boxes, so know how things work, but Renaults are new to me so I don't want to be replacing shafts if its a common diff / box issue, and vice versa. After a few hours reading I find lots of info on the circlip, but this seems rather more worrying than just lost drive, as its mechanical parts massively grinding against each other.

Since it happened though, I have still been able to both load and unload it from the trailer, and when driven carefully around the yard its working again. Selects all gears and drives as it should until a bit of load is applied

Any help much appreciated.

 

[Gaverick]

Have you dropped the oil from the box and checked if there's metal in there?

 

[scotty2hotty81]

Needle bearings on driveshaft maybe?

 

[Craig-S]

I haven't done anything yet, was just happy to dump it and have a break after bringing it home. Il have a look this week, but really didn't want to be un-necessarily stripping parts off it until I had an idea what was wrong.

 

[scotty2hotty81]

really didn't want to be un-necessarily stripping parts off it until I had an idea what was wrong.

In this case you will be doing this to determine what was going on, you cant go off what someone says on the net, is the car lowered? Maybe the shaft came out and went back in, excessive movement on the engine won't help either, I'd be pulling the n/s shaft out to check that and the diff circlip incase there is a issue with that.

 

[Craig-S]

To be honest I don't know why I wrote that, when knowing full well that's exactly what I would be doing. Its not lowered no, and the issue is 100% on the O/S.

Its outside in the rain at the moment so thought Id put the feelers out before starting, that's all. maybe Il bring it in this afternoon and have a little look.

All reported cases of the circlip problem seem to be quite civilised breakdowns. This was very much worse, like when a wheel falls off.

 

[Chip-mk1]

Circlip is passenger side.

 

[Craig-S]

Thanks Chip, just been out and stripped it down so know what the propblem is now. Il update later with pic's as it may help others in future searches.

 

[tomhunt85]

Thanks Chip, just been out and stripped it down so know what the propblem is now. Il update later with pic's as it may help others in future searches.

Please do, I'm having similar issues and need to sort it.

 

[Craig-S]

Started on the N/S, to see if the circlip was the culprit, and found the issue right away. As I think was mentioned above the worn mounts have allowed the N/S inner CV to pop out of the diff and back in again. Despite being intact there's quite a bit of damage to the circlip and gearbox housing, but that should hopefully clean up and a new circlip can still go in.

The knuckle joint has had it, and although it was still intact it fell apart once removed. Luckily all needles were retrieved.

So, hopefully a new shaft and a bit of emery paper will sort that side out, but out of curiosity I removed the O/S too, just to confirm its condition.

The grease was a little watery and it does look to have got very hot, but with no signs of damage I shall just re-pack this one.

 

[NorthloopCup]

I've got one of the circlip replacement plates if your interested? It's a significantly stronger way of holding the drive cup in place rather than the circlip that's for sure.

 

[Cub.]

What modifications are you running with the semi slicks? Cage etc?

 

[Craig-S]

I've got one of the circlip replacement plates if your interested? It's a significantly stronger way of holding the drive cup in place rather than the circlip that's for sure.

Thanks, Il look into that if this Circlip does fail, but for now I'm happy to clean it up and re-fit.

What modifications are you running with the semi slicks? Cage etc?

No cage, just a decent seat and harness.

 

[Cub.]

Suspension / bracing mods? I'm no genius, but to run semi-slicks or slicks I was under the impression you had to have upped the capabilities of the rest of the cars geometry etc?

 

[Craig-S]

There's a world of difference between 888's / A048's (semi's) and full slicks though. Agreeably I wouldn't take this Clio out on full slick's, but a medium compound semi is fine.

It has a Whiteline roll bar, welded in rear brace and some new service items up front with CL RC6 brakes.

 

[Cub.]

Ahh, a048s and 888s will be fine Just trying to figure out why the driveshaft got such a pasting!

 

[Craig-S]

I would say the 2 chicane's at Castle coombe took their toll when coupled with excessive engine movement. Il address those rubber mounts right away, But its quite annoying to find a 2 year old K-Tech invoice for £144 in the history for a set of new mounts. :S

 

[NorthloopCup]

Ahh, a048s and 888s will be fine Just trying to figure out why the driveshaft got such a pasting!

It's because they're a s**t design mate. Some fail, some don't. You pays your money, you takes your chance.

 

[STEVE.M]

It's because they're a s**t design mate. Some fail, some don't. You pays your money, you takes your chance.

See if you can find some used solid mounts on here.They`ve come up before.

 

[Craig-S]

Oh, I never bought them, must have been the previous owner.

I definitely wont be going back out without doing something. The PMS ones look good.

 

[scotty2hotty81]

Glad you found the problem.

 

[AlexW]

Suspension / bracing mods? I'm no genius, but to run semi-slicks or slicks I was under the impression you had to have upped the capabilities of the rest of the cars geometry etc?

As you saw, I was running almost entirely slick A048's on my DCi! Soft Lotus spec ones too. Made it epic.

 

[adamlstr]

Oh, I never bought them, must have been the previous owner.

I definitely wont be going back out without doing something. The PMS ones look good.

If the PMS ones are little too uncompromising for you, there's a kit from Vibratechnics too.

http://www.vibra-technics.co.uk/renault/clio_2_172_182

 

[NorthloopCup]

If the PMS ones are little too uncompromising for you, there's a kit from Vibratechnics too.

http://www.vibra-technics.co.uk/renault/clio_2_172_182

^^^^^^Just as good as the pms stuff imo.

 

[adamlstr]

^^^^^^Just as good as the pms stuff imo.

Can't comment as I've only used the vibra ones, but by far one of the best things I've done to my cup.

 

[Hoofy]

Just catching up on this.... We had a similar problem when we modified our race car, driveshafts popping out! If you've chewed the cv cup....You need to open that gearbox up and get it cleaned, there is guaranteed swarf in there even if you have found all the needles.