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Posted: Wed Nov 26, 2008 7:59 pm
by Jeremy
I'd not recommend driving directly through the Laycock overdrive, for a couple of reasons.

Firstly, it is an integral part of the gearbox tail shaft housing and uses the rear shaft, bearing, and lubrication, from the gearbox - it's not a separate sealed unit like the Fairey units. I'm sure a new front housing, with input shaft, bearings, oil seals etc could be fabricated, but doubt it'd be worth it.

Secondly, the overdrive is pretty weak. It was never very reliable even with the torque of the V6; an electric motor can probably deliver the same, or perhaps even more, torque so might well push the unit beyond it's reliable limit.

Finally, the Laycock unit won't survive being driven in reverse if engaged, although this can be easily resolved by incorporating a reverse interlock switch, as built in to the original gearbox.

Jeremy

Posted: Wed Nov 26, 2008 8:11 pm
by ChrisBarron
MalcolmB wrote:
ChrisBarron wrote:Didn't want to spoil Bob's day, but I actually think I have spotted a speck of dirt on that immaculate chassis ;-)


I noticed that as well, thought the chassis was holed at first, but it must be muck. Shocking eh. :P

Just noticed the belt drive as well. Nice. Can you tell me what width/pitch that is Bob and where you got the bits?


In all fairness I see from Bob's site that I should be a bit more humble because he's a lot more accomplished than me. Prior to this car I've only ever managed the restoration of Mini.

I'm really interested in your drivetrain Bob, and will be watching your progress with the AC system, so best of luck with that, not that it's needed !

Malcolm, I got a great quote from Cross and Morse (They'll send you free catalogues) when I was looking to put a gearbox belt drive onto my Mini, to power it from an electric motor. They offered to make a custom 80mm wide pulley and broach it with a 'special' spline for about £140 for the first one, and if I wanted 5 off it came down to £55 each

Here's their website http://www.cross-morse.co.uk/

Posted: Thu Nov 27, 2008 5:04 pm
by ChrisBarron
Jeremy wrote:I'd not recommend driving directly through the Laycock overdrive, for a couple of reasons.

Jeremy


Thanks Jeremy.

I am almost certain there is no overdrive, but your commets were interestinmg. I think I beleived the overdrive was a seperate affair, like the Fairey unit you suggested. I don't have one anyway.

Well, the car came down today from Aberdeen, it cost more to ship it than it did to buy it but I'm not complaining.
The engine bay is enormous, and there will be a huge space at the rear once I remove the 17 gallon fuel tank, so large I think my huge motor miught be able to go back there, which gets rid of a lot of the remiaing drivetrain and weight.

The interior is non existent, but I have a jigsaw and some MDF so I'll be in DIY heaven with that.

First job will be to reove the engine and ful system, and ssess it for the MOT things. One of the door steps has swelled badly and split the fibregalss due to the metal reinforcement rotting inside, but I have a neighbour who has almost finished the restoration of a fibreglass yacht who is a dab hand with the fibre stuff and resin work <wink>

I definately will have tot ake the body off, but need to find where all the bolts are, and also need to find somewhere to store the body once it is off the chassis.

I think this will turn out alright, even if I get just 30 miles range I'm going to be very happy

Posted: Thu Nov 27, 2008 7:15 pm
by ChrisBarron
Jeremy wrote:
The rear axle is a well-known weakness, as it wasn't really up to taking the torque from the V6. It's usually a Salisbury unit though, so is easy to get rebuilt.
Jeremy


Do yoiu mind if I pick your brains Jeremy.

I would really like to reverse the axle so that the diff input shaft faces to the rear rather than the front. Simply turning the axle over or around won't work because of the non-symmetrical location of the hub components and mounts.

I wonder if its possible to simply turn the axle half-shaft tubes and invert them by 180 degrees , and then turn the axle over. I haven't stripped an axle down before but can't see anything (perhaps other than locking bolts) which hold the tubes in position which would stop the axle tubes from being turned over. Have you any expereince with stripping axles ?

If I could turn the axle over the motor can go where the fuel tank is currently located and a small belt reduction drive constructed.

Chris

Posted: Fri Nov 28, 2008 10:11 am
by MB
If you want an off-the-shelf car rather than a conversion, it sounds like a G-Wiz would be right up your street.

There are a few on eBay at the moment, plus half a dozen odd second hand examples at GoinGreen (who import the car into the country). There's an active owners club and they're easy to maintain and look after yourself, but with the added benefit of manufacturer backup if you need it.

It would cost you less to buy a second hand G-Wiz than it would cost to buy an existing car and convert it.

ok - so 70mph would be out of the question with a standard car, but I suspect that if you wanted to soup up the car to hit those sorts of speeds, it wouldn't be beyond the realms of possibility to achieve that.

However, if you like the idea of a conversion (and after all, why not?) you could pick up a cheap Microcar or an Aixam or a Ligier microcar and convert those - they all weigh under 400kg, or a Reliant (the Robin was under 450kg and the Kitten was around 500kg). All these cars appear on eBay fairly regularly and never go for much money.

Citroen 2CVs have been done as well (650kg-ish?).

But then, if you've been eyeing up a Ford Puma, I suspect all of the above may be the wrong sort of car for you!

Posted: Fri Nov 28, 2008 1:07 pm
by Jeremy
Chris,

To be honest I'm not sure whether this would work or not. The devil would be in sorting out small details, like the brake mountings etc (if I've understood you correctly). The'd also be the minor issue of getting oil into (and out of) the diff case, as the filler and drain plugs would end up in the wrong place.

I did take the rear axle out of mine to get the diff fixed, but that was back around 1982 or so, so my memory of the detail is a bit faded!

I do recall that working under the car was pretty easy, with lot's of room to get at stuff. Mind you, it would have been nicer to have had to discover this following the failure of the overdrive unit, then both (stainless) exhaust systems and finally the diff, all within the space of around 5000 miles........

Sorry I can't be of more help.

Jeremy

Posted: Fri Nov 28, 2008 10:10 pm
by nino500
On the axle reversal..

It sounds like a good idea but remember you'll need room for a shaft with a couple of UJs and a sliding joint before you get to the motor in order to allow the axle to move on the suspension while the motor stays put.

On the other hand, you could mount the motor directly to the axle so they move as a unit but I think, by the way you described your motor, it would be a bit too heavy for that approach.

For the actual reversal, you may be able to turn the whole thing over, rather than seperate the tubes from the diff, and the re-weld the suspension mounts 180 degrees round. The brake back plates are usually on a symetrical four stud mounting so they should be able to be rotated 180 degrees as well, to line up with the handbrake cables and stuff...

I've never done that, though.... it's just some thoughts.

Nino.

Posted: Fri Nov 28, 2008 11:42 pm
by ChrisBarron
nino500 wrote:On the axle reversal..

It sounds like a good idea but remember you'll need room for a shaft with a couple of UJs and a sliding joint before you get to the motor in order to allow the axle to move on the suspension while the motor stays put.


Nino.


That's very true.

On teh remounting of suspension links, I was thinking i could keeop the bottom of the diff at the bottom still and just remove the halfshafts and axle tubes, spin the diff around and fit the left hand halfshaft into the old right hand diff side, and vice cersa. I recognise it would probably mean reshimming.

Yes, the motor is about, umm 50 kg ? Far too heavy for axle mounting, but I'm glad you mentioned the sliding joint because I think I may have underestimated how much free play I'm going to have left to work with.

I'll get under it in soon and get the fuel tank off, and take some measurements.

In the meantime, mark me down as a loony, because I sat in it today and in it's bare interior I let my imagination go. I'm too old to go 'brumm brummm' but I have a really good feeling about it just because of the amount of room that I have to build in battery boxes and so on, and still have the chance of keeping a couple of back seats and a useable boot.

Anyway, sorry for going a bit off topic , thanks for the comments so far.
I'll try to get a web page sorted out.

Posted: Sat Nov 29, 2008 6:58 pm
by nino500
On teh remounting of suspension links, I was thinking i could keeop the bottom of the diff at the bottom still and just remove the halfshafts and axle tubes, spin the diff around and fit the left hand halfshaft into the old right hand diff side, and vice cersa. I recognise it would probably mean reshimming.


Again, good free thinking and I'm not here trying to find flaws in your ideas but I think, if you did this, you'd be driving the crownwheel in reverse which is all very well for short distance reversing but they're designed for constant driving in one direction. (thrust face alignment on the crownwheel and pinion teeth etc.)

If you just swivelled it over, you'd still have the crownwheel in the same aligment and direction with the wheels.

Nino.

Posted: Sun Nov 30, 2008 10:34 pm
by ChrisBarron
nino500 wrote:
Again, good free thinking and I'm not here trying to find flaws in your ideas but I think, if you did this, you'd be driving the crownwheel in reverse which is all very well for short distance reversing but they're designed for constant driving in one direction. (thrust face alignment on the crownwheel and pinion teeth etc.)

If you just swivelled it over, you'd still have the crownwheel in the same aligment and direction with the wheels.

Nino.


That's right, I had forgotten about the bearings in the diff.
The same diff unit is fitted to some land rovers on the front axle and in those applications the diff would be properly set up, The axle tubes are different but might be interchangeable with the Scimitar's.

I'll keep it in the back of my mind for now but even if I don't get the motor into the old fuel tank space I can fit at least two batteries there instead.

Chris