Gearbox Rebuild

[Healey 12]

Hi
My current 5 speed gearbox is showing signs of wear , 2nd gear synchro and in first (under load ie going up hill) chatters like mad. car is a 74 240Z

So I am looking at options if any one can help.

Either rebuild mine, I have found a specialist local to me who can do the work if I get the parts . Has anyone used the gearbox rebuild kit from Torquen / Z car depot https://www.torqen.uk/nissan/240z-2...-kit-4and-5-speed-240z-260z-280z-800-697.html.

Or does anyone have a good used ZX gearbox which I believe will bolt straight in ?.

Or finally an S14 box that has been modified.?

Thanks
David

 

[Tony Mc]

These people seem to have a comprehensive selection of rebuild parts if you know what you need.

MANUAL / STANDARD TRANSMISSION - NISSAN INFINITI & DATSUN - Page 1 - Transmission Parts Distributors

NISSAN, INFINITI, & DATSUN MANUAL TRANSMISSION PARTS & REBUILD KITS

www.transmissionpartsdistributors.com

My 5-speed gearbox is also in need of a refresh but without opening it up can't be sure what is inside!
I expect it has been swapped at some point - car is US 1973.

 

[Healey 12]

These people seem to have a comprehensive selection of rebuild parts if you know what you need.

MANUAL / STANDARD TRANSMISSION - NISSAN INFINITI & DATSUN - Page 1 - Transmission Parts Distributors

NISSAN, INFINITI, & DATSUN MANUAL TRANSMISSION PARTS & REBUILD KITS

www.transmissionpartsdistributors.com

My 5-speed gearbox is also in need of a refresh but without opening it up can't be sure what is inside!
I expect it has been swapped at some point - car is US 1973.

Thanks for the link, very useful

 

[Rob Gaskin]

Old Z boxes are 'old'. The S14 is a great upgrade but are scarce now.

Yes ZX will go straight in but again old.

I have had so many gearboxes over 4 cars. My blue 240 had a superb S14 box.

It would be a real bonus if someone did a conversion for something like an MX5 box.

Thinking 'outside the box' ha ha there must be some good 4 speed boxes around, they have the advantage of top being 'straight through' so less whine.

Just rambling sorry.

 

[Ian Patmore]

Hi
My current 5 speed gearbox is showing signs of wear , 2nd gear synchro and in first (under load ie going up hill) chatters like mad. car is a 74 240Z

So I am looking at options if any one can help.

Either rebuild mine, I have found a specialist local to me who can do the work if I get the parts . Has anyone used the gearbox rebuild kit from Torquen / Z car depot https://www.torqen.uk/nissan/240z-2...-kit-4and-5-speed-240z-260z-280z-800-697.html.

Or does anyone have a good used ZX gearbox which I believe will bolt straight in ?.

Or finally an S14 box that has been modified.?

Thanks
David

Synchros for the '71A and B 'boxes (steel synchros) can be found NOS, but aren't cheap, and bearings are mostly ones off the shelf. It depends whether you have a steel or brass synchro 'box.

A lot of people have gone S14, but the point maybe coming to be cheaper to rebuild what you know than forking out for a S14 that has unknown history and the outlay cost. For me, 1st on the S14 is too tall and the gearbox was originally first put into the S30 to get over worn A & B 'boxes with modded engines. It depends what sort of engine spec you are running and how brutal you are with the 'box/engine. The '71A and B boxes are plenty strong enough for road use, but maybe not if drag racing every weekend.

Or you hybrid your '71B (steel) with '71C parts where necessary.

 

[Healey 12]

Hi Ian

Synchros for the '71A and B 'boxes (steel synchros) can be found NOS, but aren't cheap, and bearings are mostly ones off the shelf. It depends whether you have a steel or brass synchro 'box.

A lot of people have gone S14, but the point maybe coming to be cheaper to rebuild what you know than forking out for a S14 that has unknown history and the outlay cost. For me, 1st on the S14 is too tall and the gearbox was originally first put into the S30 to get over worn A & B 'boxes with modded engines. It depends what sort of engine spec you are running and how brutal you are with the 'box/engine. The '71A and B boxes are plenty strong enough for road use, but maybe not if drag racing every weekend.

Or you hybrid your '71B (steel) with '71C parts where necessary.

Hi Ian.
Is there a way of telling if I have 71A, B box without stripping it down? . The parts from Torgen are they for the 71C gear box ? but will they still fit the early gearbox if it turn's out I have that version .
Thanks
David

 

[Wrighty]

I’m in the same position. Have tried to rebuild. Replaced all bearings, synchros etc, had new tab lock nuts made for the shafts and a new fifth gear cut but still jumps out of fifth. I can’t work out what is wrong so I’m looking for an S14 box if anybody has a good one.

 

[Healey 12]

I’m in the same position. Have tried to rebuild. Replaced all bearings, synchros etc, had new tab lock nuts made for the shafts and a new fifth gear cut but still jumps out of fifth. I can’t work out what is wrong so I’m looking for an S14 box if anybody has a good one.

where did you get your bearings and syncros from?

 

[Rob Gaskin]

So much is said about which gearbox is best and how the gear ratios don't suit etc etc.

Beggars can't be choosers for road use.

The most important thing is to get a gearbox in good condition. You can work around the other details - if you have a 3.9 diff (with 5 speed box) you can't go far wrong. 3.6 is ok too but you need a bit more torque than the standard 240Z for best results.

 

[johnymd]

I have a couple of S13/s14 boxes that have already been converted. As I don't need 2 I had considered selling the one that's currently in my silver car. This box is absolutely perfect. No noises and goes in all gears smoothly. Can be tested in the car when I get it back from paint. No idea what they are worth all done and ready to go but it's there if anyone wants to make me an offer. Otherwise I'll just continue to use it. I wont sell my spare as It was a little noisy when you push the clutch down. I think that is now fixed but I haven't had a chance to try it. I do have a third box and converted bell housing which hasn't been swapped over and tested yet.

 

[MCBladeRun]

So much is said about which gearbox is best and how the gear ratios don't suit etc etc.

Beggars can't be choosers for road use.

The most important thing is to get a gearbox in good condition. You can work around the other details - if you have a 3.9 diff (with 5 speed box) you can't go far wrong. 3.6 is ok too but you need a bit more torque that the standard 240Z for best results.

When Mike (SacCyclone) picked up my car from the previous owner, he stated to Mike that he'd blown up the 3.6 diff and Mike was sceptical.

So anyway, Mike replaced the 3.6 with another one.. it's running a standard 2.8litre with a 5speed.

 

[Ian Patmore]

Hi Ian

Hi Ian.
Is there a way of telling if I have 71A, B box without stripping it down? . The parts from Torgen are they for the 71C gear box ? but will they still fit the early gearbox if it turn's out I have that version .
Thanks
David

A quick way is how the gear lever sits, if like the link, its a 71A ( numbers 1 and 2[ even though this is a 4 speed]).

https://www.carpartsmanual.com/datsun/Z-1969-1978/power-train/transmission-assembly

It still won't tell you if its a steel or brass synchro, that would be a visual.

The Torgen website is US based, so they got brass synchros, the steel synchro 'box '71B (5 speed) in North America was a sports option, so its a rare beast there. It also depends where your car was originally sold what you have, let alone if its been swapped since then. The '71A 'box was only up to Dec '71 for the UK market, so its a rarer one than the '71B box (both were steel synchros).

If you have a US import S30, the kit/brass synchros are an easier find. They are the same for the 4 and 5 speed, just an extra (different one) for 5th.

I am pretty sure that some of the '71C 'box bits only fit the'71B box, from what I am seeing. This site I look at often at what this chap is doing, and I have also purchased a few bits from him too. I gather he is well known in Japan for his S30 gearbox work.

https://www.vintagecraft-e-za.com/s30zのページ/７１系ミッションの輪廻転生/71bコンパチｃ-α２/

3.6 ratio diff, new on me, you mean 3.7 (3.69)....? R180 or R200? Need a bit more correct context...

Wrighty, I'm no expert, sounds like its not engaging properly, did you replace the springs and ball bearings for the fork selector as well (8, 9 and 10)? Use the correct synchro for 5th?

https://www.carpartsmanual.com/datsun/Z-1969-1978/power-train/transmission-control/5-speed

Oh, and the MX5 would a difficult swap as the starter is on the other side, though anything is doable..

 

[Healey 12]

Hi
Thanks for that info much appreciated . My car is a 73 240Z original UK RHD car , I have just taken a couple of pictures to help identify.

 

[Robotsan]

I have a couple of S13/s14 boxes that have already been converted. As I don't need 2 I had considered selling the one that's currently in my silver car. This box is absolutely perfect. No noises and goes in all gears smoothly. Can be tested in the car when I get it back from paint. No idea what they are worth all done and ready to go but it's there if anyone wants to make me an offer. Otherwise I'll just continue to use it. I wont sell my spare as It was a little noisy when you push the clutch down. I think that is now fixed but I haven't had a chance to try it. I do have a third box and converted bell housing which hasn't been swapped over and tested yet.

I've sent you a DM John - definitely interested in a box if you are selling one.

 

[Healey 12]

A quick way is how the gear lever sits, if like the link, its a 71A ( numbers 1 and 2[ even though this is a 4 speed]).

https://www.carpartsmanual.com/datsun/Z-1969-1978/power-train/transmission-assembly

It still won't tell you if its a steel or brass synchro, that would be a visual.

The Torgen website is US based, so they got brass synchros, the steel synchro 'box '71B (5 speed) in North America was a sports option, so its a rare beast there. It also depends where your car was originally sold what you have, let alone if its been swapped since then. The '71A 'box was only up to Dec '71 for the UK market, so its a rarer one than the '71B box (both were steel synchros).

If you have a US import S30, the kit/brass synchros are an easier find. They are the same for the 4 and 5 speed, just an extra (different one) for 5th.

I am pretty sure that some of the '71C 'box bits only fit the'71B box, from what I am seeing. This site I look at often at what this chap is doing, and I have also purchased a few bits from him too. I gather he is well known in Japan for his S30 gearbox work.

https://www.vintagecraft-e-za.com/s30zのページ/７１系ミッションの輪廻転生/71bコンパチｃ-α２/

3.6 ratio diff, new on me, you mean 3.7 (3.69)....? R180 or R200? Need a bit more correct context...

Wrighty, I'm no expert, sounds like its not engaging properly, did you replace the springs and ball bearings for the fork selector as well (8, 9 and 10)? Use the correct synchro for 5th?

https://www.carpartsmanual.com/datsun/Z-1969-1978/power-train/transmission-control/5-speed

Oh, and the MX5 would a difficult swap as the starter is on the other side, though anything is doable..

These are the pictures of my gearbox . The engine that came with my 240 was a 260 so it would not surprise me if the 5 speed came from that car as well > I have found this rebuild kit kit with Syncro rings . I Any help identifying the gearbox and if this is the correct rebuild kit would be much appreciated

 

[Wrighty]

where did you get your bearings and syncros from?

Bearing Man Ltd Shrewsbury. The originals are stamped with numbers on the side and they were able to replace like for like.

 

[Wrighty]

I have a couple of S13/s14 boxes that have already been converted. As I don't need 2 I had considered selling the one that's currently in my silver car. This box is absolutely perfect. No noises and goes in all gears smoothly. Can be tested in the car when I get it back from paint. No idea what they are worth all done and ready to go but it's there if anyone wants to make me an offer. Otherwise I'll just continue to use it. I wont sell my spare as It was a little noisy when you push the clutch down. I think that is now fixed but I haven't had a chance to try it. I do have a third box and converted bell housing which hasn't been swapped over and tested yet.

If you’ve still got one,of those boxes for sale in good condition I’d be interested. 07587778774

 

[Ian Patmore]

These are the pictures of my gearbox . The engine that came with my 240 was a 260 so it would not surprise me if the 5 speed came from that car as well > I have found this rebuild kit kit with Syncro rings . I Any help identifying the gearbox and if this is the correct rebuild kit would be much appreciated

IF your S30 is an original UK market car, the gearbox is steel synchros. The image in Monday's post are brass, these won't work. It looks like a '71B 'box.

I don't think anyone does a rebuild kit for the '71A or B steel synchro boxes, its a buy the bits separately and make a kit that way. 4 synchro rings needed, the one for 5th gear is different, but doesn't get the use compared to the others. Stuart Wilkin in Aus is a place I see often mentioned for synchros.

I have 3 or 4 bearings sitting around somewhere, that could be for sale....

I just found NOS needle bearings in Japan, badly listed. There bits for these out there, just they aren't many around.