New Driveshaft knocking

[mojobaby]

I replaced my driveshafts about 2 months ago and still have a slight knocking sound, from which side I can't work out.
I can drive at 90 km/hour and there's no problem; no knocking, no vibrations in steering wheel or the accelerator pedal. I can take my hands off the steering wheel and it carries on straight (no pulling to one side)
I can also take corners, left or right and there's no knocking.

The only time there is a knock is when I accelerate suddenly or drive up a steep hill in 1st 0r 2nd gear.
I can then feel the vibration in the steering wheel and the accelerator pedal.

I removed the driveshafts and couldn't see anything obviously wrong.

Any ideas please? I bought them at a good price from Oscaro in France and they're RCA brand.

 

[malcolm]

Is the exhaust fouling where it passes through the inner wing? If it is engine torque related it is likely to be the exhaust or possibly front gearbox mount.

 

[mojobaby]

Thank you Malcolm, the exhaust barely makes it through the hole, but thats not the sound I'm hearing. I don't think it would cause the vibrations in the steering wheel and pedal.
Could be the gearbox mount as the engine seems to shake a bit when it idles.

The funny thing is that the problem started the day after I replaced the drive shafts.

I don't know if its possible but I get the feeling that the drive shaft splines at the wheel side are slipping. Is that possible?

 

[David M]

I don't know if its possible but I get the feeling that the drive shaft splines at the wheel side are slipping. Is that possible?

I don't think that it would be possible.

*A couple of other suggestions to look at. Maybe check again, the tightness of the driveshaft nuts on the hub?
*The engine mount on the LHS should have a support that goes over the starter motor. Without it, the mount can break, creating quite a deal of harshness.

 

[mojobaby]

Thanks David, I checked the drive shaft nuts and they're fine. So is the bracket over the starter motor.

I took the drive shaft out again this afternoon (can do it in my sleep these days) and then put it back again.

I noticed a bit of play in the upper wishbone and also noticed that the rubbers on the ball joints are shot.

When my drive shaft knocking problem started 6 months ago, it was after hectic braking to avoid a cat in the road. Straight after that I heard the tuk tuk noise. Advice here on the forum was that strong braking wouldn't damage the drive shafts.
Maybe it was the ball joints and that eventually led to drive shaft damage.

I had noise on accelerating and cornering which points to the drive shaft.

 

[Piet]

Mojo, I had a similar experience many years ago. It turned out to be one of the steering rod (track rod) end eye bushes (the one that screws into the end of the steering rack. The rubber bush eventually got chewed up and partially spat out, allowing the inner and outer rings to clunk on each other metal to metal when you put power on or brakes on- the force would cause the front wheel to splay in or out and hit metal to metal. Normal driving was fine as handling was pretty nuetral and the wheel tracked away happily without vibrating. So accelerate/brake and high speed knocking sounds like that to me. If you have a later car with the different bush/rod end set up, wear in that bush would still give the same effect.

You can test by firmly grasping the front wheel at the front and back edges and shaking/rocking it back and forth rapidly as if trying to steer the car. If you get play without the steering wheel moving and even better some clunking then that's it.

Good luck!

 

[mojobaby]

Thanks Piet, your diagnosis makes perfect sense. Those ball joints rubbers were wrecked so I did already replace them when I did the drive shafts. I checked and they are still perfect.

I took your advice and rocked the wheel from left to right and I had quite a lot of movement accompanied by a noise. I traced it to the back end of the upper suspension wishbone.

There is a large bolt that secures the wishbone and it goes through rubber bushings. The right hand bushing looks really bad and that is the cause of the movement and knocking sound. Hopefully by replacing it, it will solve my problem.

So thanks everyone for your help and advice. I'll probably take it out tomorrow or Sunday and post some photos.
The manual says that I'll need a press to remove it and replace it with a new one.

 

[mojobaby]

I removed the wishbone suspension and found the bushing to be badly worn.

The inner metal tube is not supposed to move but it came out very easily because the surrounding rubber is worn thin.





Ads a temporary fix I jammed in some plastic conduit. There is now no movement at all in the wheel. The plastic should last a while at least until my parts arrive

 

[Azazello]

.
The manual says that I'll need a press to remove it and replace it with a new one.

I did the job in a (small) bench vise, the one you can buy by lidl on special offers for 10 euros or so, helping with an old bearing and some socket of the right diameter...

 

[mojobaby]

Because of the air filter, carburetor and manifold, it is almost impossible to see the strut support that goes over the starter motor. It is also extremely difficult to also stick your hand down there.

In 2011 I had a starter motor problem and removed everything and took the starter out thinking that I could fix it, but I couldn't so I put everything back together and took the car to a garage. At that stage I didn't even know where to get a new or 2nd hand starter motor from.

I was very careful as it was the first time that I had worked on my car and I know for a fact that I replaced that strut support.

So imagine my surprise when I decided to double check on the strut and found it missing. So thanks David M for reminding me about it.
There's also supposed to be a stud on the side of the engine where the strut is supposed to fit, but that's also missing.

 

[Giles]

Mojobaby, it looks like i'm going to be after various cosmetic (e.g. interior light switch/cover) and mechanical parts (those cylinder liners). Since I'm new to R4 and you are also in SW France, where do you go for parts?

 

[mojobaby]

Hi Giles I usually get my parts from Der Franzose in Germany, takes about 4-5 days to get here. I got my drive shafts from Oscaro in France. There's also Melun Retro passion in France, but I've never ordered anything from them.

I also keep an eye on Le Bon Coin for 2nd hand parts. Just type in Renault 4L and then choose Equipement Auto in the next space. There are a couple of engines at a good price but I've just typed in "Renault 4L Chemise" and that's where you'll find your cylinder liners.
You have a 956cc right? With the funny shape piston tops? You'll find a set there now, selling from Bordeaux if I remember correctly. It's got 4 liners but only 2 pistons.
Then further down, a full set of everything for 180Euro, from somewhere up North

 

[Giles]

Thanks, all v helpful! I shall check them this evening.

Just struggling to get the PC working after win10 upgrade (email client kaput), so bit of a backlog to get through...