5 Speed box: A little bit of the old "Vince Reynard magic"..
Posted: Thu Aug 22, 2019 3:13 pm
Now the gearbox is out of the car, it's time to apply a little bit of Vince Reynard magic to the gear change. There are a few items to be improved.
First up the gear shift. In order to address this I have removed the rubber "bellows" spring which had gone gooey after years of attack from engine oil. Vince supplied me with a spare (thanks!) and although it has a split it's leagues better than mine. I cut the old one off, then heated the anti sizzle device with a blow torch until the rubber had melted enough to allow me to pull it apart. The inside of the rubber is like a bush, it has a steel tube that fits tightly onto the lower part of the shift, so I drove that off with a hammer and wrench. Next up, examination of the ball joint. All good, surprisingly, though a little rough from years of gritty oil. I've cleaned it all and applied LM grease, then fitted the replacement bellows (much easier on the bench than fitted to the gearbox). For now, a fat washer under the circlip to add a little extra preload.
Second. When moving to the 3rd/4th gate, I can see that there is a lot more motion than is necessary. I didn't have the same problems as Vince did (not engaging correctly due to too much lateral movement) but I thought I could tighten it up a little. In his video, Vince used an O ring for this purpose but for now (and raher experimentally) I've put a small plastic tie wrap round the slider bar to act as a sort of spacer. It's loose so the ratchet block doesn't get in the way.
Here's a quick demo of the improved shift. Click-click-click.
https://www.youtube.com/watch?v=_Om6hrL8_ZY
Third mod - 5th gear gate spring is too strong. It's a fat little thing that sits under the cover bolted to the left hand side of the gear box, just below the gear shift ball joint. The way to weaken a fat spring like this is to grind it down a bit (the sides, not the ends) so that the wire that makes up the coils is thinner (hence, weaker).
The spring is held in a bolt with a couple of nuts and you need to try to turn it as you go so that you get an even grind. Take it off the bolt periodically and refit to the gear box in order to test the feel of the 5th / reverse gate action. I also ground the ends a bit to make it shorter (thus, reducing the preload when fitted).
Fourth mod - the famous reverse gear plunger fix. The plunger assembly is there to hold the gearbox in 5th gear, but like the gate spring it's a bit too strong, facilitating what I call a "manly heave" to get out of 5th gear. One problem with this is that the box always jumps into 4th as you are pulling the stick so hard, and I wonder if this is good for it. Probably not!
Anyway, the plunger's spring and pin are accessed under the gearbox behind a huge domed nut. All I did was take the spring out and grind it back a bit (shortening it). This has the same effect as the more common "add an extra washer to the dome nut" approach, but saves me the hassle of finding a suitable washer. It's readily accessible under the car, anyway, so can be fettled further if need be. Some care is needed here as you can end up with the car jumping out of 5th if you go too far. So grind a little, test, grind, test, and so on is the order of the day.
Next we need to think about attaching the top half of the gearshift to the bottom half, where the anti sizzle bit is located. Following Vince's method I have put some M10 nuts on a bolt and then used Araldite to lock it all into place. It's setting as I write this post.
I've also cut a matching thread in the top of the lower stick. I had to grind it down a little as the M10 die would not go round the shaft - too fat.
So there we are. Hopefully a much improved gearshift awaits thanks to advice and info obtained from Vince Reynard. Much obliged, sir!
First up the gear shift. In order to address this I have removed the rubber "bellows" spring which had gone gooey after years of attack from engine oil. Vince supplied me with a spare (thanks!) and although it has a split it's leagues better than mine. I cut the old one off, then heated the anti sizzle device with a blow torch until the rubber had melted enough to allow me to pull it apart. The inside of the rubber is like a bush, it has a steel tube that fits tightly onto the lower part of the shift, so I drove that off with a hammer and wrench. Next up, examination of the ball joint. All good, surprisingly, though a little rough from years of gritty oil. I've cleaned it all and applied LM grease, then fitted the replacement bellows (much easier on the bench than fitted to the gearbox). For now, a fat washer under the circlip to add a little extra preload.
Second. When moving to the 3rd/4th gate, I can see that there is a lot more motion than is necessary. I didn't have the same problems as Vince did (not engaging correctly due to too much lateral movement) but I thought I could tighten it up a little. In his video, Vince used an O ring for this purpose but for now (and raher experimentally) I've put a small plastic tie wrap round the slider bar to act as a sort of spacer. It's loose so the ratchet block doesn't get in the way.
Here's a quick demo of the improved shift. Click-click-click.
https://www.youtube.com/watch?v=_Om6hrL8_ZY
Third mod - 5th gear gate spring is too strong. It's a fat little thing that sits under the cover bolted to the left hand side of the gear box, just below the gear shift ball joint. The way to weaken a fat spring like this is to grind it down a bit (the sides, not the ends) so that the wire that makes up the coils is thinner (hence, weaker).
The spring is held in a bolt with a couple of nuts and you need to try to turn it as you go so that you get an even grind. Take it off the bolt periodically and refit to the gear box in order to test the feel of the 5th / reverse gate action. I also ground the ends a bit to make it shorter (thus, reducing the preload when fitted).
Fourth mod - the famous reverse gear plunger fix. The plunger assembly is there to hold the gearbox in 5th gear, but like the gate spring it's a bit too strong, facilitating what I call a "manly heave" to get out of 5th gear. One problem with this is that the box always jumps into 4th as you are pulling the stick so hard, and I wonder if this is good for it. Probably not!
Anyway, the plunger's spring and pin are accessed under the gearbox behind a huge domed nut. All I did was take the spring out and grind it back a bit (shortening it). This has the same effect as the more common "add an extra washer to the dome nut" approach, but saves me the hassle of finding a suitable washer. It's readily accessible under the car, anyway, so can be fettled further if need be. Some care is needed here as you can end up with the car jumping out of 5th if you go too far. So grind a little, test, grind, test, and so on is the order of the day.
Next we need to think about attaching the top half of the gearshift to the bottom half, where the anti sizzle bit is located. Following Vince's method I have put some M10 nuts on a bolt and then used Araldite to lock it all into place. It's setting as I write this post.
I've also cut a matching thread in the top of the lower stick. I had to grind it down a little as the M10 die would not go round the shaft - too fat.
So there we are. Hopefully a much improved gearshift awaits thanks to advice and info obtained from Vince Reynard. Much obliged, sir!