Technical What is the best way to get synchromesh? 126 engine and trans. swat? Best year? Thanks

[Nedsly]

what is the best way to get synchromesh in my 500? 126 engine and trans. swap? Best year? Thanks

 

[the hobbler]

what is the best way to get synchromesh in my 500? 126 engine and trans. swap? Best year? Thanks

You don't need to do a complete engine/gearbox swap to get a synchro gearbox in a 500. The 126 gearbox will fit straight in, but you have to fit 500 drive-shafts (the 126 shafts are too long) and transfer the bell-housing from the 500 gearbox onto the synchro box (different starter location). In order to effect a drive-shaft swap, you have to take the bell-housing off anyway, so no problem, or much extra work, anyway. But why fit a synchro box? the 500s box is actually a better box, and it is not difficult to learn how to "double-de-clutch" (down-shifts) and to "heel and toe" so that you can brake as you're down-shifting.
If you are fitting new 500 drive-shafts, it is well worth checking the condition of the rubber/aluminium coupling on the stub-axle and renewing the sliding coupling on the shafts. Get the BEST sliding coupling that you can---the cheap ones do not have the spline area heat-treated and the splines will stripout of the coupling---usually in a very embarrasing place! If the coupling hasn't got any 'blueing' rond the splines area, it probably hasn't been properly heat-treated.
When removing the gearbox, you will find it easier to remove/refit the engine seperately---not a difficult job. With the gearbox out, check the condition of the 2 gearbox mounts--they are not expensive, so if in doubt, replace.

 

[Nedsly]

You don't need to do a complete engine/gearbox swap to get a synchro gearbox in a 500. The 126 gearbox will fit straight in, but you have to fit 500 drive-shafts (the 126 shafts are too long) and transfer the bell-housing from the 500 gearbox onto the synchro box (different starter location). In order to effect a drive-shaft swap, you have to take the bell-housing off anyway, so no problem, or much extra work, anyway. But why fit a synchro box? the 500s box is actually a better box, and it is not difficult to learn how to "double-de-clutch" (down-shifts) and to "heel and toe" so that you can brake as you're down-shifting.
If you are fitting new 500 drive-shafts, it is well worth checking the condition of the rubber/aluminium coupling on the stub-axle and renewing the sliding coupling on the shafts. Get the BEST sliding coupling that you can---the cheap ones do not have the spline area heat-treated and the splines will stripout of the coupling---usually in a very embarrasing place! If the coupling hasn't got any 'blueing' rond the splines area, it probably hasn't been properly heat-treated.
When removing the gearbox, you will find it easier to remove/refit the engine seperately---not a difficult job. With the gearbox out, check the condition of the 2 gearbox mounts--they are not expensive, so if in doubt, replace.

Thanks so much.

 

[dapedza]

what is the best way to get synchromesh in my 500? 126 engine and trans. swap? Best year? Thanks

I’m doing the job at the moment. And I’ve made some mistakes you can avoid.
Plenty of 126 synchro boxes out there. You can peer through the top cover to get an idea of their condition, but you really need to pop off the forward casing to see the rest of it. If you need to strip the box, it’s simple enough. Plenty of videos out there. You can change the bearings & seals whilst you’re there. All very cheap.
When you split the bellhousing from the gearbox, the differential, crownwheel and driveshafts will come out as one unit. You need to be careful at this point. Check your pinion & crownwheel for damage. Do not disturb the bearing preloads. The driveshafts can be replaced if need be without disturbing the preloads.
You can replace the thrust bearing and clutch friction plate while you’re there.

 

[Nedsly]

I’m doing the job at the moment. And I’ve made some mistakes you can avoid.
Plenty of 126 synchro boxes out there. You can peer through the top cover to get an idea of their condition, but you really need to pop off the forward casing to see the rest of it. If you need to strip the box, it’s simple enough. Plenty of videos out there. You can change the bearings & seals whilst you’re there. All very cheap.
When you split the bellhousing from the gearbox, the differential, crownwheel and driveshafts will come out as one unit. You need to be careful at this point. Check your pinion & crownwheel for damage. Do not disturb the bearing preloads. The driveshafts can be replaced if need be without disturbing the preloads.
You can replace the thrust bearing and clutch friction plate while you’re there.

Thank you sooo much. Just starting this cult initiation. First I cover myself in dirty oil.