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army2a
25th June 2012, 09:43 PM
hey guys, how much do fairey overdrives go for and how strong are they?

JDNSW
26th June 2012, 06:14 AM
Manufacture of them by Rovers Down South ceased in December last year (see Rovers Down South Fairey Overdrive (http://www.faireyoverdrive.com/)) so there is no 'new' price.

Second hand ones go for somewhere round $500-$1000. Mine cost $500 with a Landrover attached, but I had to spend nearly as much again on parts. Most parts are available, but many of them are expensive.

How strong are they? They generally withstand operation OK for standard Rover engines, provided they are only used in third and fourth gear. Operation in first or reverse can easily break them if used with full throttle and a sudden load such as losing and then gaining traction. But no different if used in low or high range.

If buying one second hand, ensure that all parts are there. Likely to be missing is the linkage and bracket for this, and the drive dog that replaces the gear on the mainshaft of the gearbox.

Problems. The oil reservoir is small, and oil can be chucked out the breather - I extended the breather. Oil level must be checked regularly, especially if the overdrive is used on the highway. The drive dog is susceptible to wear, and will eventually lose drive totally. While the dog is only US$125, the bit it engages with is the mainshaft, which is US$350, and wear takes place on both.

In my view, having had one for a number of years, I would not get one again. The Rover engines are quite happy to turn at the required revs for the 110kph speed limit, and the lower rpm resulting from the overdrive is only a slight advantage.

My advice would be that if you have a Rover engine, either four or six, forget the overdrive - its only real advantage is as a splitter, especially in low range. If you have another engine, perhaps look for another type of overdrive, although these are rarer and more expensive. For example Heystee Automotive Online Store (http://www.heystee-automotive.com/onlineshop/catalog/advanced_search_result.php?keywords=overdrive&search_in_description=1&osCsid=Q9bf1CUvkhlrDOzesfFlhUl6zS5&x=9&y=11)

John

C00P
26th June 2012, 10:53 PM
In my view, having had one for a number of years, I would not get one again. The Rover engines are quite happy to turn at the required revs for the 110kph speed limit, and the lower rpm resulting from the overdrive is only a slight advantage.

My advice would be that if you have a Rover engine, either four or six, forget the overdrive - its only real advantage is as a splitter, especially in low range. If you have another engine, perhaps look for another type of overdrive, although these are rarer and more expensive. For example Heystee Automotive Online Store (http://www.heystee-automotive.com/onlineshop/catalog/advanced_search_result.php?keywords=overdrive&search_in_description=1&osCsid=Q9bf1CUvkhlrDOzesfFlhUl6zS5&x=9&y=11)

John

I've got a "Roverdrive" on my Series 3. Made in Canada, and reputed to be fairly rugged. Not had it long, so can't comment on the durability. However, can be used in any gear (even reverse) and shares its oil with the transfer case (the oil level in the TC is lifted by half a litre and there is a dipstick as part of the kit). This may have overcome the Fairy problems with the oil.
I find it very handy when in hilly country as it allows you to find a gear that matches the climb, especially if its a long hill.
Cheers

Coop

JDNSW
27th June 2012, 05:56 AM
Yes, the Roverdrive is reputed to be a lot better in all respects - but I have no experience with them.

John

army2a
27th June 2012, 09:17 PM
thanks guys for your response, if the revs only drop a small amount i might not worry about it, especially running 35s

garrycol
27th June 2012, 09:41 PM
thanks guys for your response, if the revs only drop a small amount i might not worry about it, especially running 35s

Hang on - 35s - what gearbox and tfr case are you running? I would have thought a series box would not survive very long with 35s.

If you have an LT95 then we are talking about a different Fairy Overdrive.

What Fairy Drive are you interested in - determined by tfr case.

Garry

kowanyamakid
8th July 2012, 06:11 PM
army2a'

I bought one of these new in 1976 for $450 (I think), had it fitted by the LR agent in Orbost, VIC. The sales pitch at the time was that it could be used in all gears. I was a timber contractor then in the high country with a '68 88". I used that overdrive as a splitter in all gears, low or high range and often with four wheel chains on.
It lasted 18 months then stripped the gear as mentioned above. I had been advised to chuck the original mainshaft gear, nut and T/Case end plate under my seat, just in case.
Well I didn't and without them there is no drive and I took 2 days to walk home and a month to recover the vehicle. This is the only time I have ever walked home driving a 2A and I have not forgiven that Fairy.
I sold the bits for $25 and never looked at another one again.

However, with the advent of the internet I am surprised to see how many of these are still in use all over the world without too many problems (sort of). I still think they are a weak link and as other have said, have got by without since then quite happily. Sometimes, I feel I need a 5th gear, so if someone would buy me a Roverdrive I would give it a go. That seems to be a stronger bit of kit altogether.


cheers

Tom
1964 GS109

RaggedJoe
9th July 2012, 01:28 PM
The Rover engines are quite happy to turn at the required revs for the 110kph speed limit


My '74 109 with 2.25 Petrol doesnt really feel happy at more than 75kph. All original gearbox diffs etc. 7.50 x 16 tyres. No idea what RPM it is doing.

Always fancied an overdrive to avoid the "Where's 5th gear" feeling, but she doesn't do much road work, so it's not worth getting one anyway.

It feels like it would explode if I tried for 110! But perhaps I am overly sensitive and just need to thrash it harder?

RJ

isuzurover
9th July 2012, 01:35 PM
thanks guys for your response, if the revs only drop a small amount i might not worry about it, especially running 35s

A 2.25 would seriously struggle with 35s AND an OD.

The fairey OD is noisy and weak. The Toro is quieter and slightly stronger. The roverdrive is better again, however if you are spending Roverdrive money, you would be better off with an R380 5-speed conversion.

JDNSW
9th July 2012, 01:53 PM
My '74 109 with 2.25 Petrol doesnt really feel happy at more than 75kph. All original gearbox diffs etc. 7.50 x 16 tyres. No idea what RPM it is doing.

Always fancied an overdrive to avoid the "Where's 5th gear" feeling, but she doesn't do much road work, so it's not worth getting one anyway.

It feels like it would explode if I tried for 110! But perhaps I am overly sensitive and just need to thrash it harder?

RJ

At 75kph you are not even up to the maximum torque figure of 2500rpm, arguably the most efficient speed for any engine (but aerodynamic drag goes up as the square of the speed, and by 75kph on an aerodynamically inefficient vehicle like this will already be the majority of resistance!).

The Rover engines are quite happy to operate at high rpm, and at 110 engine noise will be negligible compared towind noise, body reverberation and tyre noise, and most likely gearbox/transfer case noise.

John

RaggedJoe
9th July 2012, 02:15 PM
Thanks John.

Might push her a bit harder next time out! But 110! The noise of all the things you mention would be enough to put me off, and stopping her from that pace in an emergency with LT tread on the tarseal, well let's just say I think it might be a challenge! Front mounted handwinch vs unwary Japanese hatchback / pedestrian doesn't bear thinking about. :eek:

isuzurover
9th July 2012, 02:31 PM
Thanks John.

Might push her a bit harder next time out! But 110! The noise of all the things you mention would be enough to put me off, and stopping her from that pace in an emergency with LT tread on the tarseal, well let's just say I think it might be a challenge! Front mounted handwinch vs unwary Japanese hatchback / pedestrian doesn't bear thinking about. :eek:

When my IIA had a 2.25P, I could sit on >75 MPH! on a flat highway if I wanted to (no OD at that stage). 75 was as high as the speedo went... The needle was about where 80 mph would be if the markings had continued.

Even with a 2.25D and no OD (but with earplugs!)
http://s124.photobucket.com/albums/p29/isuzurover/bris-perth/?action=view&current=Bris-Perth336.jpg

Lotz-A-Landies
9th July 2012, 03:00 PM
When my IIA had a 2.25P, I could sit on >75 MPH! on a flat highway if I wanted to (no OD at that stage). ...
... Even with a 2.25D and no OD (but with earplugs!)
and not minding that the car would be jumping all over the road! :o :D

My 202 powered SIII, no O/D will easily do 115KPH, so long as I can stand the flapping of the tarp.

isuzurover
9th July 2012, 03:56 PM
and not minding that the car would be jumping all over the road! :o :D ...


If you have stiff springs, skinny rag tyres and and no load then maybe...
My IIA with soft springs and 235 or 285 radials has always handled quite well on the highway.

Michael2
10th July 2012, 03:01 PM
I had a fairy O/D on my SIII 109, and it was happy to cruise at 110kph on the flat.

I don't think it would cope well with bigger tyres.

They lose a lot of oil through the pin hole sized breather. I drilled it out and fitted a larger breather that was in common with the t/case. Better still would be one that drains back to the o/drive. It ran on Moreys, as it had some wear when I bought it, but that worked pretty well. Even though there was a slight whine, the 28% drop in revs and engine noise still made it worthwhile.

The 110 300Tdi has a Roverdrive on it. At 100kph the wind buffeting the snorkel is the loudest noise in the cab. At that speeds the Tdi is doing 2,000rpm. The only issue with the Roverdrive has been the lever's occasionally knocked into neutral on bumpy steep ascents.

As for top speed and handling, I had a 3 litre Nissan Diesel and 5 speed in a SIII 109 at one stage (Do NOT do it!!!). I can say the car was still stable and predictable on the road at 140kph (in the NT when it was legal).

army2a
11th July 2012, 08:17 PM
thanks for the replies guys, much appreciated. I dont think i will worry about the overdrive. especially with 35s i dont need any other weak links in the driveline.

mick88
11th July 2012, 08:28 PM
A 2.25 would seriously struggle with 35s AND an OD.

The fairey OD is noisy and weak. The Toro is quieter and slightly stronger. The roverdrive is better again, however if you are spending Roverdrive money, you would be better off with an R380 5-speed conversion.

Where do I get an R380 5 Speed conversion.
I am in the thro's of "about to" order a "Roverdrive"

mick88
11th July 2012, 08:32 PM
Manufacture of them by Rovers Down South ceased in December last year (see Rovers Down South Fairey Overdrive (http://www.faireyoverdrive.com/)) so there is no 'new' price.

Second hand ones go for somewhere round $500-$1000. Mine cost $500 with a Landrover attached, but I had to spend nearly as much again on parts. Most parts are available, but many of them are expensive.

How strong are they? They generally withstand operation OK for standard Rover engines, provided they are only used in third and fourth gear. Operation in first or reverse can easily break them if used with full throttle and a sudden load such as losing and then gaining traction. But no different if used in low or high range.

If buying one second hand, ensure that all parts are there. Likely to be missing is the linkage and bracket for this, and the drive dog that replaces the gear on the mainshaft of the gearbox.

Problems. The oil reservoir is small, and oil can be chucked out the breather - I extended the breather. Oil level must be checked regularly, especially if the overdrive is used on the highway. The drive dog is susceptible to wear, and will eventually lose drive totally. While the dog is only US$125, the bit it engages with is the mainshaft, which is US$350, and wear takes place on both.

In my view, having had one for a number of years, I would not get one again. The Rover engines are quite happy to turn at the required revs for the 110kph speed limit, and the lower rpm resulting from the overdrive is only a slight advantage.

My advice would be that if you have a Rover engine, either four or six, forget the overdrive - its only real advantage is as a splitter, especially in low range. If you have another engine, perhaps look for another type of overdrive, although these are rarer and more expensive. For example Heystee Automotive Online Store (http://www.heystee-automotive.com/onlineshop/catalog/advanced_search_result.php?keywords=overdrive&search_in_description=1&osCsid=Q9bf1CUvkhlrDOzesfFlhUl6zS5&x=9&y=11)

John

So John...what do you recomend..."Heystee" or "Roverdrive" ????????

I am about to order one for my Series 3!


Cheers, Mick.

isuzurover
11th July 2012, 08:37 PM
Where do I get an R380 5 Speed conversion.
I am in the thro's of "about to" order a "Roverdrive"

1. Find a defender R380 for sale at a reasonable price.
2. Buy a "stumpy" R380 bellhousing from Ashcroft. Ashcroft Transmissions - Short Bellhousing R380 (http://www.ashcroft-transmissions.co.uk/index.php?act=viewProd&productId=157)
3. Do the mods to fit an LT230 t-case, or buy a 2nd adaptor from ashcroft:
Ashcroft Transmissions - Series 5 speed kits (http://www.ashcroft-transmissions.co.uk/index.php?act=viewProd&productId=83)

Note that is you can find an LT77 5-speed from a 200Tdi defender that will replace steps 1 and 2, but the LT77 is not as strong.

series3
12th July 2012, 02:02 PM
How does a LT77/R380 gearstick location go in comparison to original? big mods needed?

Sam

isuzurover
12th July 2012, 02:30 PM
How does a LT77/R380 gearstick location go in comparison to original? big mods needed?

Sam

Not far off if you use a defender box. Just some minor tunnel mods. If you use a disco R380 then the shifter will be between the seats.

landrover dave
24th July 2012, 08:11 PM
Fairey overdrives have lots of weaknesses, the worst being wear on the mainshaft. The small needle rollers wear longitudinal grooves causing the overdrive to whine its head off. A mainshaft is nearly as much as a new unit!
Also around 500ml of oil is not alot!
A high speed transfercase is the best bet, but they are only made in uk now.
I wouldnt recomend 35" tyres on any rover, you lose too much braking efficiency and the loss of gearing is amazing. Gearing is what made the Landy so much better than jap 4x4s.

garrycol
24th July 2012, 09:28 PM
I wouldnt recomend 35" tyres on any rover, you lose too much braking efficiency and the loss of gearing is amazing.

That is a generalisation that is not quite true - there are a couple of variants that have 35" tyres as standard and their braking is as good if not better than other series rovers and they have no loss of gearing.

Garry

landrover dave
27th July 2012, 09:07 PM
Technically a 900x16 is 36". Aus didnt officially get any 101's, the rapier training vehicles were on loan, and we didnt get any 1 ton Landies. Forward control 2A and 2B had a different t/case to "normal" series, and the 2A FC I did drive had totally crap brakes. My comment was aimed at more common and everyday Landies/Rangies. I do stand corrected owners of these classics!

That is a generalisation that is not quite true - there are a couple of variants that have 35" tyres as standard and their braking is as good if not better than other series rovers and they have no loss of gearing.

Garry

Martin S
10th August 2012, 02:51 PM
I fitted a Roverdrive to my Seiers III in 2004 and since then I have put on over 100,000km with it.
I have no problems to report at all. Change the oil as per specs and away you go.
A handy tip is that a tab cab be mounted onto the mounting bracket for the OD lever. This can be used as a lifting point as it sits over the CoG. Very handy for getting the whole drivetrain in and out due to the extra length with the OD.
Cheers

Martin