Trio In Gear Selection Bother Shocker!

[Sandy 191]

Back along I had a sudden problem selecting gears and feared the worst, a well known ATR problem, the dreaded synchros/selectors. I posted about it on the ATR forum but then strangely, it went away and things seemed to back to normal. Then yesterday I was doing an emergency upshift from 2nd to 3rd and it baulked again, for a moment I couldn't get any gears, but before I slowed down too much I managed to get 4th and carry on. Changing gear wasn't too much bother until I stopped and couldn't get first without turning the engine off, as though the clutch was dragging.

The clutch action felt normal though and I got myself home.

This morning it hadn't rectified though, so I had to cancel my plans for today (not funny, I've got alot on) and went up to the workshop and set about taking the box off, which is no laughing either!

 

When I got it off, a few bits of clutch centre fell out! So I took the clutch off to find this:

 

For those of you that don't know, when I fitted the engine, I got the standard Honda ATR plate centre removed from the organic plate and riveted onto a custom cerametallic paddle plate. It's done 15k since I fitted it and apart from the previous glitch it's been fine. But it's now clear the hardened section that connects the springs to the centre, has shattered. This section is a Honda original (the same as the OE clutch) and has not been modified. I wonder how many standard clutches have gone this way and the ensuing selection problems have precipitated premature synchro and selector damage? The paddle plate I use does have a more violent bite than organic material and I've got a fair bit more torque than standard, but I'm not generally as violent as many drivers!

 

The good news is the flywheel and cerametallic pads have not worn unduly and seem to be coping very well with the school run/B road/track use combo I subject them to.

[steve@cornwall 100]

I,ve just had similar gear selection probs, followad by the clutch not disengaging. Springs in the plate were shattered. also did a clutch on a zx recently where the plate had cracked between the springs - this went bang in quite a big way, had to replace gearbox as well as clutch

[danpug 1]

Honda reliability eh..............................

[Batfink 201]

Honda reliability eh..............................

 

it got him home, pugs just stop lol

[Sandy 191]

Yes, fortunately all the other bits survived having pieces of hardened steel floating about, but some miracle.

[Sandy 191]

Got a new plate made, cerametallic paddle with a pattern sprung centre. I finally got it all back together last night after having to rebuild the box twice due to a minor error in putting the fifth synchro together! Bit of a sense of humour failure there.

Huge credit to Colin for his help and patience!

[steve@cornwall 100]

Got a new plate made, cerametallic paddle with a pattern sprung centre. I finally got it all back together last night after having to rebuild the box twice due to a minor error in putting the fifth synchro together! Bit of a sense of humour failure there.

Huge credit to Colin for his help and patience!

 

Holy sh1t --- That's quicker than most factors can supply an off the shelf kit! what happened to "drekkly time?"

[Batfink 201]

better than just buying a paddle clutch off the shelf?

[Sandy 191]

We can get them made nearby for a fraction of the usual cost, fortunately

[Sandy 191]

I stripped the clutch plate today to ascertain the exact nature of the failure.

 

Here's the plate complete with the rivets ground down to release the centre, the plate appears to be undamaged on casual inspection, which is probably all it gets during a change:

 

Lifting off the front part reveals the shattered centre piece underneath, I've put some of the shrapnel found in the bell housing back into it's original position so you can see where it has fractured, there's impact damage on the rivets:

 

Note the scraping damage to the springs, I'll come back to that.

Here I've lifted the centre off so you can clearly see the damage. The clutch still mostly works in this condition of failure, but drags when disengaged:

 

Here's a close up of the fracture:

 

My summary of events goes as follows, including the earlier failure which seemed to clear up!

 

1. Violent gearchange causes the hard clutch centre to impact the rivets, fracturing 1 or 2 of the spring retainers.

 

2. The springs become dislocated and rub against the cover/flywheel causing clutch drag.

 

3. Due to clutch drag, gears are very hard to engage unless input/output shaft speeds are matched well and gears impossible to select at a stand still with the engine running.

 

* In this condition, if the gears are selected forcibly, the synchromesh will be damaged, possible distortion of selectors too. Fortunately I seemed to escape gearbox damage at this stage.*

 

4. The dislocated springs become worn down, so dragging ceases and the normal clutch action resumes, but with an amount of drivetrain "shunt".

 

5. All is apparently well until I hit the problem again with a violent gearchange, undoubtedly causing the remaining spring retainers to fail and repeat the problem.

 

6. This time I realise there's clutch drag and limp home by driving without the clutch, matching engine speed between gears and using the starter to pull away. I'm very wary of damaging the synchros, and so exercise extreme sympathy!

 

7. Clutch comes out for inspection and gearbox is stripped for inspection. Clutch found to be damaged, gearbox, thankfully and mercifully, isn't!

 

My conclusion is that the hardened section of the clutch centre is prone to failure with violent use. The friction material I'm using is less forgiving than the conventional organic material, but I'm positive that the standard clutch (which the centre of mine is), is vulnerable to this damage with extreme use. The first symptom of this problem would be difficulty in gear selection, which would be most apparent on 5th and reverse, because they share the same selector movement. If the car is rested immediately at this stage, for a clutch change, I'm confident damage to the gearbox would be avoided, but of course forcing the gears to continue driving could easily bring the gearbox failures that would logically follow and are quite possibly secondary to the real problem, the clutch plate.

 

But don't quote me on that