Help with my Clunk and Grind

[24OZ]

No, this is not some new dance routine .

Occasionally i have trouble selecting 1st gear (Grind) as well as reverse (Clunk or Grind). Whats up?? I dont have a leaky Clutch Master cylinder, or at least I cant see any visible leaks.

Is it just a case of adjusting my clutch pedal? What else should i look at??

Can someone breifly go through some steps please.

Its my 73 240Z.

Many thanks in advance for any suggestions.

[Alfadog]

Crunch sounds like your synchros are tiring (except reverse, which doesn't HAVE a synchroniser... clunk I don't know, but I've got that too in reverse

[HS30-H]

Hi George,

Just like Alfadog says - its probably the synchros in your gearbox that are getting tired. If you don't know what these are - basically they are small toothed rings which ensure that your gears mesh together smoothly as you change gear. They wear out eventually, and the only way to fix it is to replace them - which means a full transmission strip down.

Meeting this problem, I have noticed that may people start looking around for a good used transmission to swap in. This will almost certainly have the same problems, or will eventually develop them - so its a false economy. If you replace the synchro rings and freshen up the 'box with a few new bearings and shifter bushes, you will not believe the difference. The transmission is one of the main places that the driver interfaces with the mechanism of the car, and if its working right it is a real joy to use. I've driven quite a few "other people's" Z cars, and it is amazing how many of them are soldiering on with a tired and baulky transmission that makes it pain to drive the car.

Mind you, you have not got a synchro on reverse gear - so that will always be a slow shift. If you can't get it to engage reverse smoothly ( without the crunch / graunch ) even after doing it slowly and deliberately, then you may have a clutch or clutch operating system issue after all. Did it start doing this suddenly, or has it gradually got worse?

Alan T.

[Daniel]

Tranny worn?Its possible.I vote that you need a new clutch.I know it doesnt slip or make noise -yet.Bad syncro maybe,but unless you are bad about downshifting hard in to first gear I doubt.It would seem that second gear syncro would be the one to go huh?Since there is no reverse syncro try this.Put the car into first gear,then go to reverse.Thats a practice to use even when everything is correct.It'll stop that grinding. Havefun!! Daniel oh yeah- There is no adjustment.The slave cylinder on the tranny is self adjusting on the 72 and 73.Check that for leaks also.After driving the same 240 since 73.I have had that symtom a few times before.Each time replacing clutch/pressure plate was the fix.

[24OZ]

Thanks all for all your great suggestions . All noted.

Alan- no its gradually doing it on and off, somedays it never happens at all.