Engine Freshen Up to this ........

[Rod]

Since my last response yesterday I have thought a little more about the clutch / gear issue. While I am going to go through everything systematically from the beginning again, I am leaning towards a bent clutch fork.

Prior to the sprucing up of the old girl, I had an ongoing issue with the clutch. I think I documented this previously but when I depressed the clutch, I would get a knock, and when I put the motor under load, I could also get the same knock. As it turned out, I had the clutch plate in back to front. I am suspecting this may have put excessive load on the clutch fork and bent it.

While I never had issues with the clutch and engaging gears previously, maybe with the new clutch and pressure plate, it has come back to haunt me. May be with the bent clutch fork, I have now got little adjustment of the slave cylinder pushrod.

Anyway, I will get there at some point. Hopefully it's not in a years' time.

Have a ripper.

Cheers Rod

[ardiesse]

Clutch in backwards.  Been there, done that.  Which machines arc-shaped grooves into the heads of the flywheel bolts, and as my grandfather (a fitter/machinist) was wont to say, "None genuine without this mark".

And now I remember.  The spigot bearing collapsed (early Humpy), and I had to take the clutch off to replace the bearing, and when I put the gearbox back, the clutch adjustment was way off, and I wondered why that was, as I hadn't replaced anything.  Started the car, went to reverse off the ramps, and it made an awful racket as I let the clutch out.  Said a few choice words to myself about paying attention, and then did an engine-out to fix my mistake.  It took less time than working under the car.

Sorry, but I have to ask: Is your clutch still in backwards?

If you confirm that your clutch fork's bent, I have a couple of the indestructible forged FX-FJ ones.

Rob

[Rod]

I am glad I am not the only one to have had a plate in back to front. Interestingly 30 odd years ago, I pulled the box off the motor, thinking it may have been loose flywheel bolts. You would have thought I should have been more observant at the time for the wear on the bolts. Nope, put back together and the knock continued. It wasn't until I pulled the motor for this current rebuild, that it was evident by the wear on the bolts that it was in back to front. How the clutch even worked was beyond me as the pressure plate had significant damage to the internals, not the facing. As for now, I surely hope it's not in back to front Rob. I was a like a carpenter, "measured twice, cut once". But who knows with me. Time will tell.

Last night I used your "wiggle" technique on the pedal pushrod. I am more than confident now that the end play is correct. All this means is I am one step closer to a bend clutch folk.

Thanks for you offer of clutch folks. I have a few but not sure of type and condition. I just need to find them.

Have a ripper.

Cheers Rod

[Rod]

Well, well.

I have taken the slave off the box and clutch fork covers off. It is definitely something inside as the first thing I noticed the the minimal gap between the back of the fork and the gear box house. I would say 4mm. This would not allow an inch travel when the cluch is depressed. I had a look inside to the best of my ability and I don't think the folk is bent when comparing it to another I have.

When I replaced the clutch I also replaced the throwout bearing. I have a hunch that this may be the problem as I have a feeling reading about differences in these. Anyway it is only conjecture as I will need to remove the engine to investigate anyway.




Have a ripper. Cheers Rod

[Rod]

Took motor an box out today to investigate the clutch issue.

1. Stuck Clutch - check. All clear.
2. Bent / cracked fork - check. All clear. Compared against another fork and the profile is exactly the same.
3. Clutch plate - check. Correct orientation. Checked anyway and it can't go the otherway round. The plate is a little different to the original ie: its much more 'beefier" on the side that needs to be opposite the flywheel.
4. Thrust bearing - While they look identical, the was replacement was 2mm short and also 2mm short from the mating serface of the fork and bearing to the face of the bearing. The old old is more thatn servicable, so I will just reuse this.
5. Spigot bearing - check. Mmm, might be the issue. I rememebr investigating another post where the spigot wasn't inserted far enough. I checked and I was able to drive it home another 3mm. I clearly remember doing this when I first installed it and I compared the distances against another crank. I was confident it was in the right spot but possibly not. I had it installed up to where the taper of the crank finished. Now it is in 3mm further than this spot. Gee I hope I haven't put it in to far.

I hope to reassmebly tomorrow I hope.

Cheers Rod

[Rod]

Well that was an eventful exercise.

Motor out and back in and the issue still persists. When I assembled the fork, it was closer to the front of the box when it engages with the pressure plate fingers than with the new throw out bearing. But when I reinstalled I just had a feeling it still wasn't far enough forward. Sure enough, when I put the slave cylinder on I practically ran out of adjustment at the point where I had spec'ed free travel. It just seems if the fork is bent but there was no sign of this and it compared exactly to a spare I had.

I am trying to figure why this would be the case. The flywheel has been machined but surely this minimal amount would not effect it. The only other thing that comes to mind that I may have been sold the wrong kit ie: pressure plate is thinner than standard which would make the fingers closer to the flywhee. I am really only "clutching (like that one) at straws". The only way I will know is by pulling the box again, measure the pressure plate thickness and compare this to an original.

To recap, I can place into gear when the motor isn't running but can't when it is going. I can start it in gear but it wants to run. Interestingly I tried all four gears but can't get reverse when starting. I will adjust again tomorrow but I don't like my chances of getting to the bottom of this.

Have a ripper. Cheers Rod

[Errol62]

Very frustrating Rod. Sorry can’t offer much insight, as I replaced my crash box with an all synchromesh and concentric slave a while ago.


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[Rod]

Thanks Clay. It has me stumped. Looks like engine out again. At least I hadn't reinstalled grill, bonnet etc... Must have thought there was going to be an issue.

All I can gather it is the fork but there is no sign of damage (bent of broken), it s profile is exactly the same as a spare I have (unless its bent but cant see any sigh) and there was no problems when the gears box was previously in before rebuild.

I think I need to do some investigation with the pressure plate.

Here is a photo which shows I am out of adkustment. This is excessive compared to my ute.



As a bonus I adjusted the linkages and now can select reverse.

Have a ripper Rod.

[ardiesse]

Rod,

This is the stuff of nightmares . . .

I have a few original pressure plates, and I can measure their height from flywheel face to pressure plate fingers.  I can even drop the gearbox off "Found Object"s motor and measure dimensions if you want.

I think that with a new clutch plate, the pressure plate fingers should sit essentially flat.

One way you can cheat is to put washers under the clutch fork pivot ball, but you'd most likely run out of thread before the adjusting nuts get into the right position.  I think that measuring the height of the pressure plate fingers above the flywheel face seems like the best thing to do, but you have to go through all the hassle of another engine-out to do it.

A little Googling reveals that the Exedy GMK6021 clutch kit is the right one for grey-engined Holdens.  It has a 200 mm clutch plate, annoyingly 3 mm less in diameter than the original 8" plate, but close enough; and the pressure plate looks like an exact copy of the original Holden one.  If all else fails . . .

Best of luck,

Rob