Heres a question for all you 500 technical guys.
Can you rebuild a 500L gearbox with full synchro gears?
Can you rebuild a 500L gearbox with full synchro gears?
Technical 500 Gearbox - synchro?
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Technical 500 Gearbox - synchro?
AndrewHarvey
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I'm building a 126 and that has synchro on 2/3/4
Considering a 5th ........
Considering a 5th ........
Sean from what I have read in the past you probably could do it but in the long run it will probably cost more than sourcing a synchro gearbox. Apparently the 500 crash box is the most robust, as to allow for the synchro parts they thinned all the gears down for the synchro box.
This place in Italy would sell your all the bits but they would probably cost you more than the car is worth?
http://www.bacciromano.com/?p=prodotti&l=eng&cat1=25&cat2=79&mar=4
This place in Italy would sell your all the bits but they would probably cost you more than the car is worth?
http://www.bacciromano.com/?p=prodotti&l=eng&cat1=25&cat2=79&mar=4
I can vouch for that Tony. Although the 126 BIS has a big increase in power, which doesn't help, I had to cannibalise a gearbox in order to keep mine going after things went bad and I ended up driving 30 miles in second gear to get home. Those were the days (not all that long ago) when I easily found a whole car locally for £50.
Stick to the non-sychro, again, it's part of the uniqueness of the car. Not something just to tolerate but actually very enjoyable in my very odd opinion.
In answer to your original question- yes you can install synchromesh in a 500F gearbox. The main gearbox casing and extension housings are interchangeable - only bell housing is different.
I personally prefer the synchro gearbox- All my 500's have been converted to Synchro, all are slightly different:
1) My first is a hybrid transmission that I built around 1991 which is built into a 500F casing and uses a 500F differential so it is nice and quick off the line although runs out revs at the top end like a normal 500- haven't touched it in over 20 years now.
2) My second is in my daily driver 500F which is a standard Niki (Aircooled 126) transmission with a Nanni 5 speed conversion- has given 10 years of excellent service although the first gear is starting to get a bit noisy now. This is a much better solution as it gives easy cruising at 100km/h and will top out at 130km/h with an absolutely standard Aircooled 126 650 engine.
3) My most recent is a hybrid transmission for my Giardiniera which uses a Niki transmission with Nanni 5 speed conversion and 126 Bis bellhousing so it bolts up to the Giardiniera Flat engine- has done 1500km now and is a pleasure to drive!
The Synchromesh and 2-3-4 gears in the 126 are virtually indestructible- unfortunately the hardening of the first gear and cluster on the Polish-built transmissions are generally poor quality and often randomly wear out 2 or 3 teeth with consequent jumping out of first gear. Very occasionally they can also break teeth off the differential crown wheel but this is rare and in my opinion worth it for the better gear ratio.
In conclusion- if you are planning to use your 126 as a daily driver in traffic or do motorway mileage I would recommend the conversion. Irrespective of whether you convert to 126 transmission I would thoroughly recommend the 5 speed conversion- if you have a 650 engine it is absolutely the best way to transform the driveability and longevity of the car as it allows you to use the torque to push the car along without having to sustain high revs.
If you are going to just do the occasional weekend drive then the crash box may seem an appealing challenge to some but if you are going to use the car more regularly- rebuild a 126 transmission with a new first gear and cluster (not necessarily with genuine parts...) you will probably find it will outlast the car!
I personally prefer the synchro gearbox- All my 500's have been converted to Synchro, all are slightly different:
1) My first is a hybrid transmission that I built around 1991 which is built into a 500F casing and uses a 500F differential so it is nice and quick off the line although runs out revs at the top end like a normal 500- haven't touched it in over 20 years now.
2) My second is in my daily driver 500F which is a standard Niki (Aircooled 126) transmission with a Nanni 5 speed conversion- has given 10 years of excellent service although the first gear is starting to get a bit noisy now. This is a much better solution as it gives easy cruising at 100km/h and will top out at 130km/h with an absolutely standard Aircooled 126 650 engine.
3) My most recent is a hybrid transmission for my Giardiniera which uses a Niki transmission with Nanni 5 speed conversion and 126 Bis bellhousing so it bolts up to the Giardiniera Flat engine- has done 1500km now and is a pleasure to drive!
The Synchromesh and 2-3-4 gears in the 126 are virtually indestructible- unfortunately the hardening of the first gear and cluster on the Polish-built transmissions are generally poor quality and often randomly wear out 2 or 3 teeth with consequent jumping out of first gear. Very occasionally they can also break teeth off the differential crown wheel but this is rare and in my opinion worth it for the better gear ratio.
In conclusion- if you are planning to use your 126 as a daily driver in traffic or do motorway mileage I would recommend the conversion. Irrespective of whether you convert to 126 transmission I would thoroughly recommend the 5 speed conversion- if you have a 650 engine it is absolutely the best way to transform the driveability and longevity of the car as it allows you to use the torque to push the car along without having to sustain high revs.
If you are going to just do the occasional weekend drive then the crash box may seem an appealing challenge to some but if you are going to use the car more regularly- rebuild a 126 transmission with a new first gear and cluster (not necessarily with genuine parts...) you will probably find it will outlast the car!
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OP
OP
Cheers Damon.
Now if the casing is the same, then its just a case of changing the internals.
So if I wanted to convert my box to synchro, what parts would I need?
Presumably all components on the layshaft.
Primary gear cluster.
Reverse gear? or is this the same?
Are the selector rods/forks the same?
And if I changed all these parts using my original diff, I suppose I would need to check the pinion is in the correct position as the layshaft gear dimensions may have changed causing the pinion to be a different distance from the crown wheel?
Now if the casing is the same, then its just a case of changing the internals.
So if I wanted to convert my box to synchro, what parts would I need?
Presumably all components on the layshaft.
Primary gear cluster.
Reverse gear? or is this the same?
Are the selector rods/forks the same?
And if I changed all these parts using my original diff, I suppose I would need to check the pinion is in the correct position as the layshaft gear dimensions may have changed causing the pinion to be a different distance from the crown wheel?
From memory the forks, main housing, selectors and bearings are the same but everything else is different- it shouldn't be difficult to find a 126 gearbox with a blown first gear set which will be a lot cheaper than trying to assemble all the individual parts.
The simplest way to do it is to simply rebuild the 126 box and put the appropriate bell housing on to suit your engine.
The 126 selector housing has a much better sealing arrangement around the shaft and later ones have provision for a reversing light switch.
If you want to use your pinion and crownwheel you can usually get away with transplanting the pinion shaft with front bearing and shims and the diff/side bearings as a matched set- the overall dimension of the individual layshaft components is the same between 500 and 126.
The 500 and 126 transmissions are quite simple and even as a novice you can't go too far wrong...
OP
OP
Now heres a question for you.
When I dismantled my gearbox, I carefully secured the 3 striker rod bearings & also the 3 striker rod lock rollers.
But then I found a 5.5mm diameter bearing on the bench. I do not know where it came from, I don't recall having any bearings on the bench prior to this and I can find no mention of it anywhere in the Haynes manual or see anywhere in the gearbox that it could be used.
Could you please set my mind straight that this bearing does not belong in the gearbox?:shrug:Ahhhh
When I dismantled my gearbox, I carefully secured the 3 striker rod bearings & also the 3 striker rod lock rollers.
But then I found a 5.5mm diameter bearing on the bench. I do not know where it came from, I don't recall having any bearings on the bench prior to this and I can find no mention of it anywhere in the Haynes manual or see anywhere in the gearbox that it could be used.
Could you please set my mind straight that this bearing does not belong in the gearbox?:shrug:Ahhhh
Sean..I sent you an email
AndrewHarvey
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Hi - I also had the same experience and have been worrying what this bearing does - could someone put my mind at rest please
Re-build due to start next week
Many thanks
Re-build due to start next week
Many thanks
OP
OP
Cheers Damon, i am not sure exactly what you mean. I cant find it on any diagrams. But i will check it out later to see if i can work out what you mean.
OP
OP
