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Paul and Judson
09-05-2010, 12:46 PM
We are new Land Rover owners. We have a 1972 Series III 88 Land Rover.

Next to the drivers seat, coming out of the seat bulkhead is a short lever which has a home made short wooden handle. The person we bought it from says it is used to change the gear ratio and is not an overdrive. Some questions:

What is it?
How is it used?

Thank you for your help.

NickDawson
09-05-2010, 01:06 PM
Wish I had an answer - mostly curious! Can you post some pictures, including shots of how it connects to the transmission?

spacemutt
09-05-2010, 01:21 PM
Sounds like an overdrive to me, as technically, that's what an overdrive does. It ups the output gearing. It's not another gear, as it works in any gear.

If it is, then when you reach terminal velocity in 4th (or maybe 3rd), dip the clutch, push the lever forward, and re-engage clutch. When slowing down it's simply the same procedure, but pull the lever back.

I suggest you try it at low speed (1st gear) so if it goes wrong then there isn't the inertia of the vehicle hurtling along at 60 miles per hour to mangle up your gearbox. But under normal operation, only use it in 3rd or 4th.

Paul and Judson
09-05-2010, 04:47 PM
Sounds like an overdrive to me, as technically, that's what an overdrive does. It ups the output gearing. It's not another gear, as it works in any gear.

If it is, then when you reach terminal velocity in 4th (or maybe 3rd), dip the clutch, push the lever forward, and re-engage clutch. When slowing down it's simply the same procedure, but pull the lever back.

I suggest you try it at low speed (1st gear) so if it goes wrong then there isn't the inertia of the vehicle hurtling along at 60 miles per hour to mangle up your gearbox. But under normal operation, only use it in 3rd or 4th.
thank you for your reply. i have been doing some research. i dont have the typical shifter associated with the fairey overdrive. i think i might have what rovers north calls a high ratio transfer box (hrt 1002). would that make sense? are you familiar with this? how is it used? how is it different from an overdrive?

disco2hse
09-05-2010, 05:14 PM
You sure it's not a PTO?

pictures, pictures, pictures

superstator
09-05-2010, 06:08 PM
The HR t-case just permanently raises the gearing in high-range to about what an overdrive would do. There's no lever to control it, it's an always-on deal.

Second (third?) the pictures. Sounds like an overdrive with a homemade linkage.

Tim Smith
09-06-2010, 07:08 AM
Sounds like an overdrive. Roverdrive, Toro or a Fairey they all work the same. The levers can be slightly different but that is dependent on the install.

Take some pictures of the underside of the truck. We are interested in the back of the transfer box in the area of the rear drive shaft.

adkrover
09-06-2010, 08:03 AM
I don't want to throw this discussion off course but did we ever find out what the mysterious large "R" lever was for in another chaps Rover about a month ago?

And on this thread, the original post said the lever came from the bulkhead. My overdrive lever comes from the side of the center tunnel. I can't imagine the geometry of the linkage if it truly comes from the bulkhead. Maybe it's just a confusion about what exactly the bulkhead is.

adkrover
09-06-2010, 08:07 AM
Ok, now that i read it again i see t is from the seat bulkhead. I would call it a seat box but same difference. I am again thinking it sounds just like the magic "R" lever.

Paul and Judson
09-06-2010, 10:32 AM
3838

3839

Here are two images. One showing taken to show small lever and the other taken to show the device.

Any ideas? Thanks to all for your help and interest.

Apis Mellifera
09-06-2010, 01:40 PM
Overdrive - possibly a Toro. That's how they actuate. BTW, one on the nuts holding it on is really loose.

disco2hse
09-06-2010, 03:27 PM
Ok, now that i read it again i see t is from the seat bulkhead. I would call it a seat box but same difference. I am again thinking it sounds just like the magic "R" lever.

Probably better if you don't try to hijack the thread and post on the thread you are referring to.