I owned a series 2, 2A Land Rover called bum-bum that I bought it January last month. Unlike my series III which has all syncromesh in all gear, series 2 and 2a do not have syncromesh in its first, second and reverse. any attemp to shift into these gear will produce a crunching sounds which is not healty for the landy. I am trying to find in the internet on how we can changing gear correctly and found this tutorial.
the actual link is in here :http://members.ozemail.com.au/~mikeleys/
and here is the actual content :
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How to use your non-synchro gearbox.
The Problem.
You have just climbed into your "new" Series I, II or IIa and you have been told that the gearbox does not have synchromesh on first or second gear. Not knowing what to do, you start the old girl up, go to put it into first (or reverse) and are greeted by a small crunch. You get over this and move off in first. You move the lever to second and are greeted by another even bigger crunch. The change up to third is uneventful as is the change into top but when you try to change back into second, you are shocked by the crunch that results. What to do? How do you handle this tractor gearbox without destroying it?
First I should say that these gearboxes are very strong but they are not indestructible so some attempt at using correct gear changing technique is recommended if you and your gearbox are to be friends for some time. What follows is a detailed description of "double shuffling or double de clutching" These are the techniques necessary to achieve quiet gear changes and long life from your gearbox.
The basic problem is that your gearbox has no synchromesh on first, second or reverse gears. Modern gearboxes like the R380 have synchro on all gears including reverse so that anytime you change gears, the teeth will not grind as the gears which are trying to mesh have been "synchronised" or made to turn at the same speed to that when they engage, there will not be any speed difference between them and they will just slide quietly together. In your Land Rover, this only happens on third and forth gears.
How do you do it?
The First - Reverse Problem
When you first start the engine, depress the clutch and select first or reverse (or second for that matter), you may be greeted by a grating of gears. This is because the engine is spinning the front part of the gearbox but the part connected to the wheels is stationary. When you depress the clutch, the front part of the gearbox (the primary pinion, constant gears and layshaft)be disconnectedd from the engine and start to slow down and will eventually stop. If the oil in the gearbox is hot, this will take some time and if you attempt to select an un-synchronised gear (1,2,R), the spinning gears will meet the stationary gears and result in a crunch. The simple solution to this is to always select ( or at least part select) 3rd or 4th gears so that the synchromesh will stop the moving gears and then select the desired gear. If you still get a crunch, your clutch is not fully disengaging.
Normal gear changing
Changing up.This is the easy one. Put simply, you need to do some extra clutch work to get a smooth change. You need to take your foot off the clutch while the lever is in neutral and then put it back on while moving the lever to second.
1. Accelerate to about 10 - 15mph in first gear.
2. Depress the clutch and move the lever to neutral.
3. Allow the engine revs to fall so that the revs will match the road speed in second gear.
4. Depress the clutch and quickly engage 2nd gear.
That's it. You need to practice to get just the right delay at stage 3 and if you fluff it and get a hand full of teeth, you may have to engage neutral, gently blip the throttle with the clutch out and then depress the clutch again and engage 2nd. If you need to blip the throttle, you have waited too long at stage 3.
Changing Down
This is more of a challenge and depends to some extent on your ability to gauge the right amount of rev increase (blip) to give the engine during the change.
1. Slow to about 20mph in third gear. (Later you can try other speeds)
2. Depress the clutch, move the lever to neutral
3. Blip the throttle
4. Depress the clutch and immediately select 2nd gear. The success of the gearchangee will depend on your getting the blip right.
The higher the road speed, the bigger the blip.
That's it.
Once you get those two changes under control, you are ready to try the 4th to 2nd and the 2nd to first. Both are quite easy but the 4-2 change needs a bigger blip. You can also change up and down from high to Low transfer too using the same technique but here, the revs must be doubled (changing down) or halved (changing up).
Have fun getting it right. It takes a while but is quite easy with a little practice.
Michael
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