Thread: Oh, wise old buggers.

Probably depends on the context, but I expect that it refers to the period when gearboxes were just beginning to change from sliding gears. The next step was a constant mesh gear, which later would acquire synchromesh. But the advantage of constant mesh is that it enables you to have the gears helical - if engagement is by sliding gears, the gears must be straight cut, which are always noisy.

An example would be the Rover box adopted in 1932. Initially it had constant mesh on 2 and 3, and relied on a free wheel in conjunction with a clutch brake for easy gear changes. First and reverse remained sliding gear and noisy, but 2/3 were "silent" as they were constant mesh. After WW2, this box got synchromesh added, but only to 3/4, and this was adopted for Landrover from1948-1971, without the freewheel*, when the box got constant mesh on first and synchro on all forward gears. *freewheel was used in the transfer case of early 80" with full time four wheel drive.

Originally Posted by V8Ian

Yes, I'm looking at you, JD and Jerry.
What is a silent 2nd/3rd gear? It seems that the silent gear is always the penultimate ratio.

Unfortunately the 2nd gear on my Dormobile has a rather loud whine on it when changing from 3rd to 2nd gear, so not very silent Ian

Hopefully somebody will tell me the problem

Originally Posted by jerryd

Unfortunately the 2nd gear on my Dormobile has a rather loud whine on it when changing from 3rd to 2nd gear, so not very silent Ian

Hopefully somebody will tell me the problem

I can't diagnose the problem Jerry, but I know how to fix it.

At full volume.

Originally Posted by V8Ian;[URL="tel:3200129"

3200129[/URL]]I can't diagnose the problem Jerry, but I know how to fix it.

At full volume.

You’re assuming the Dormobile has dashboard lights.

If "silent" constant mesh gears are noisy, the problem is almost always due to misalignment of the gears. This is usually due to one or more of the bearings in the gearbox being worn, allowing the gears to move slightly out of mesh. However, if it has a Holden engine, it is possible that the problem is that the flywheel housing adaptor is not sufficiently accurately made, keeping the input shaft misaligned, which in turn probably results in the mainshaft being misaligned. Of course, in this case, it is only a matter of time before there are one or more worn bearings!

No assumptions John, I know it has dashboard lights, heck, it's even got a kitchen sink!

Originally Posted by V8Ian

No assumptions John, I know it has dashboard lights, heck, it's even got a kitchen sink!

My Oka has one of those. Dashboard lights are hit and miss.

[QUOTE=JDNSW;3200146]If "silent" constant mesh gears are noisy, the problem is almost always due to misalignment of the gears. This is usually due to one or more of the bearings in the gearbox being worn, allowing the gears to move slightly out of mesh. However, if it has a Holden engine, it is possible that the problem is that the flywheel housing adaptor is not sufficiently accurately made, keeping the input shaft misaligned, which in turn probably results in the mainshaft being misaligned. Of course, in this case, it is only a matter of time before there are one or more worn bearings!

/QUOTE]

It has a 200tdi diesel motor fitted