clonking , gbox or half shaft?

[Scott560]

Hi All,

So I finally had cause to inspect the lude, something sounded a bit scrape-y , so I jacked it up and spun the wheels to reveal worn out front discs are slightly scraping the calliper/pad wear thing, no big deal.

But whilst i was on my back, i thought id check what has dogged the car since i bought it, a small amount of drivetrain backlash. There is no issue as speed, but slowing down for speed bumps, or slowly coasting in traffic is a real pain. clonking each time i roll on and off the power/engine braking.

From what i could tell, there is no play in the wheel bearings, no play in either inner or outer CV joints to drive shaft..

There is a tiny bit of up/down/left/right movement from where the inner CV joint sits in the bearing holder on the passenger side, about 1 or 2 mm. However, i dont believe that is cause for the amount of play, and certainly not the cause of the noise.

What i can hear though, is a distinctive metalic clonk in the gearbox. Its been like this for almost 4 years, there is no pending death as far as i can tell, and it hasnt got any worse in my ownership. The question is, what could it be?

I'm no expert on the honda gearbox, but its almost as if there is no selective shim or similar to preload the diff, to keep it tight, hence it banging left and right due to the helical drive gear. Anyone else had this? Car was in neutral, jacked up on one side only, sound came from the gearbox when either front roadwheel was rotated by hand (And direction changed).

The car did at some point a few years ago before my track day have new honda mtf-94 gbox oil, which made no difference to the noise (or feel of the box).

Anyone else had this?

[Vtecmec]

The gearboxes do have a good amount of play (no apparent preload) like you describe. Have you checked the half shaft bearing?

[Scott560]

other than wiggling the inner CV, no. There is a small amount of play, but it seems to be the clonking/jolting that is related to the gearbox play...

Possibly related, rarely do i launch the vehicle, but last time i did, there was a fairly large amount of banging and vibration on the whole front end, possibly related to CV joint or this half shaft bearing?

[Vtecmec]

Sounds more like CV joints, or mounts?

[wurlycorner]

or mounts?

That was the first thing I thought - front and rear engine mount.
However, if the backlash can be felt in the box when checking by hand from the wheels, then perhaps not...

[Merlin]

Sounds more like CV joints

I'd say this. Anytime I have had shaft issues it was the inner CV joints. The spider bearings had worn. You can get an idea if it is them by jacking the car up, out of gear, and slowly rotate the wheels back and forth until you can hear/feel any little graunches.

Possibly related, rarely do i launch the vehicle, but last time i did, there was a fairly large amount of banging and vibration on the whole front end, possibly related to CV joint or this half shaft bearing?

That sounds like wheel hop to me.

[Merlin]

There is no issue as speed, but slowing down for speed bumps, or slowly coasting in traffic is a real pain. clonking each time i roll on and off the power/engine braking

Are you 100% sure that the pads are not too loose inside the carriers? I have had it once where I removed too much from the ends in the pads and they rattled in the carriers, and clonked on light braking.

[Scott560]

there is definitely no play in where the shaft meets any of the CV joints.

With my hand on the shaft (lol), and spinning the wheel, i can feel the 2 are definately connected 100%. EG, there is no slack in that part of the drivetrain, its solid. The only play is where the passagner side inner CV is held by the bearing/bracket, but only 1 or 2mm.

There is no notchiness or anything untoward, apart from the clonking in the gearbox and what seems like a huge amount of play.

Last time i experiences something like this, it was in a rover 620Ti, where the gbox has lost its oil, and the diff had gone bad. When parked up , engine off and in gear, the car could rock forward backwards about 1/3rd of a wheel revolution, Diff exploded shortly afterwards!

without taking the gearbox apart, it almost feels as if the crown wheel thats bolted to the diff is loose, its really odd. Thing is, if it was bad, i would have expected my 3 years of hard driving and a track day to have killed it...

Whens the next lude meet up ? wasnt there a RR day at some point?

[Scott560]

deffo not the pads, the clonking is clearly heard inside the gearbox, and not from the disc/pad area.

[Vtecmec]

The half shaft bearing should have no play at all. 1-2mm is more than mine had and I could feel its effects at crawling traffic speeds.