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Hi guys,

I've got an R33 GTST making 235 rwkW.

Usual problems with synchros - been nursing the gearbox for years on smurf's blood.

On the freeway today in 4th under acceleration the clutch started to slip (did it once, then I deliberately did it once more to check I wasn't dreaming). Also the takeup point seemed higher than usual before I hopped on the freeway.

It was a pretty gentle cruise also - not like an organic clutch that's taken a thrashing and will recover a bit when it cools down.

Hopefully I haven't trashed the flywheel, but it wasn't making horrible noises like rivets scraping.

Looking for guidance on the things that should be replaced when the gearbox and clutch is out.

Not looking for upgrades of gearsets/selectors or anything, just re-built back to standard.

Also looking for recommendations on what clutch I should put in.

Read on another thread that I should stick with factory synchros.

What other bits should typically get replaced (eg bearings etc) on a gearbox re-build - assuming I don't have any cracked gears/selector forks etc.

At this stage I'm assuming I'm up for:

new clutch plate, pressure plate, throw out bearing

machine the flywheel

replace synchros

I'm quite mechanically sympathetic on the old girl, but it does do a few track days a year, and occasional drags.

I'd prefer not to have the car back together and someone say, "why didn't you replace blah while you had the 'box out?"

Also any recommendations of who to go to in Brisbane?

Probably more important, PM me if you know people I should stay away from (please don't flame anyone in the thread)

cheers

Mike

baulk springs, retainers I think they are, replace them as well. Just make sure its done right because they can fall out

It's not an easy job and don't even attempt it if you dont have a GOOD (really, not just any old) puller kit and might need an oxy set or something to heat the gears up. One of them is a bitch to get off from what I remember

Having re-read your post thought maybe you are getting someone to do all the work, in which case go for it, just make sure its not going to cost more then just replacing the box

Thanks 89CAL,

I'm unlikely to do it myself - thought about it, and have a friend who has rebuilt Ford toploaders numerous times...

One of the reasons I posted this thread (not that I asked) was to get some idea of what's involved - your tip on replacing the baulk springs and retainers needing good pullers and an oxy leads me to think I'll leave it to the professionals - especially applying heat to gears - I'm wary of applying heat to something that's presumably already heat treated.

I'd also need a dummy shaft to set the clutch up, and a torque wrench (and a decent puller kit).

I'm happy to buy tools where it makes sense (and I've no idea where my decent quality torque wrench disappeared), and have reasonable mechanical ability and friends with skills.

A new 'box is $3K from JustJap - I'd prefer not to put a 2nd hand one in (unless it's re-built) as it's synchros will be just as flogged.

Thanks for the tips

cheers,

Mike

The gearbox rebuilds fairly fiddly, mainly because you need to make special pullers and bits to get it apart.

As for clutch im selling an almost brand new coppermix for very very cheap ;)

I had a chat with a gearbox guy today.

He mentioned that getting the right synchros can be tricky (which I suppose is understandable as the car was never sold in Australia), and depending on the type of synchro (1 piece, more than 1 piece) will make a massive difference to the parts cost.

For import cars his suppliers will often ask for a sample to ensure they send the right part.

Does anyone know the part numbers for the synchros for a 1997 Series 2 ECR33 GTST? or even better a list of all part numbers for the gearbox?

I'd like a better idea of what I'm up for before the box comes apart, as it's way dearer to re-build the box than to replace the clutch, and I may decide to squander the opportunity to fix the box while it's out and just nurse it for a few more years.

Mike

To be honest mate.

It is more cost effective buy a brand new OEM Nissan gearbox.

They are well under $3k from memory. I know just jap and kudos supply them. But I think they can be found cheaper than what they sell them for.

To be honest mate.

It is more cost effective buy a brand new OEM Nissan gearbox.

They are well under $3k from memory. I know just jap and kudos supply them. But I think they can be found cheaper than what they sell them for.

Jusy Jap sell them for just over 3k I think. Would be nice to find a cheaper one around. Thinking about replacing nine sometime

  • 3 weeks later...

A mechanically minded friend recommended I do a little more fault finding before dropping the gearbox - particularly taking it out cold from an engine bay perspective to see if the clutch slipped (ie possible vapour locks in the clutch line) - did that, couldn't get the clutch to slip in high gear on the freeway.

Came home and bled the clutch and got some new fluid in there - the old stuff was looking pretty manky.

Pedal feel better, and no slipping on a short drive, top gear freeway.

All good so far...I'll take it for a longer drive tomorrow - still quite likely my clutch is on the way out, but I may get a bit more out of it...

Noticed quite a lot of squeaking in the clutch fork action during the bleeding process.

On one of my discussions with Jim Berry he mentioned the only lube you should put anywhere near any clutch is graphite powder (but obviously keep it away from the friction surfaces).

My question is can you get to the clutch fork pivot by pulling back the dust boot, or any other way without taking the gearbox out?

Can you get access to squirt a bit of graphite powder in there, without getting any on the friction surfaces?

Cheers

Mike

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