Night Train

I gave up on B100. I was losing so much power and economy even after a service, filter change and timing/tuning check that it wasn't viable.

No snow here, just lots of sparks. I've been outside welding the first parts of my pole trailer project.

Have you checked the axle location? Worn bushes might allow front or rear axles to 'steer' a little.

I remember a similar thing happening to a friend's Series Land Rover. We cut a round hole in the bulkhead and got at it that way. The hole was then covered over with a steel disc and some self tappers for future access. Can't remember what engine it was though, BMC diesel perhaps.

Was that made or bought that way? I've just not seen or heard of extendable car sized trailers in the UK, seems to be an American thing.

If it had a head on it then it wouldn't look so weird. Give it a few years and you'd see them in the shops as 'The ideal pet for your kids!'.

With the drawbar extended nose weight wouldn't be a problem, it will be more of an issue to not over load the hitch. I can get about 3/4 of the trailer length in front of the axle. Can anyone see any problems with the drawbar being extendable?

I painted my tow hitches but only because people didn't see then and would bang their knees on them when trying to cross the road. I painted the 30ton hitch on the back on my 6x6 bright pink to make it more visible as cars parking behind would do it by feel and leave big gouges in their bonnets. Didn't make any difference, nor did painting it yellow on black so I figured car drivers just liked bumping it.

I've seen that before. It looks so wierd without a head on it, kinda creepy.

Ha, my people smuggling plan has been scuppered!

You could fit a couple of large rivnuts from the outside and bolt downwards into the roof. Or if you prefer having a bolt sticking out then you could wind in a bit of treaded bar and lock it with a nut and washer on to the roof. This makes it possible to silicone the thread in the rivenut so it doesn't leak. As for getting up there, I used to just walk straight up the front bumper, wing and roof.

Are the lugs original? Could they be for some kind of tyre chain or wheel track system given that they are on both inside and outside of the rim. I remember seeing photos of 21/2 ton GMC trucks in WW2 having twin wheels fitted on all axles and individual wheel tracks on each duel wheel.

So does that mean that Hi-Lifts are now off topic having little to do with Land Rovers?

I use a Skoda Octavia for work and the technical specifications say that the maximum nose weight is 60kg and the maximum trailer weight is 1300kg braked, 500kg unbraked. According to NTTA the minimum nose weight should be 50kg.

For stability you might want to have some location for the toe of the jack on the lift points. This could be as crude as a couple of bits of plate to stop the toe from sliding around or it could be a reinforced locating hole as found on the back of a Defender crossmember. You can then use the Defender adaptor on the Hi-Lift.

This is a bit OT but it is my next project. I want to build a pole trailer for work that I can use closed as a short open box trailer and extended as a timber trailer. It will have a max weight of around a ton as a short box but only about 400kg as a long timber trailer. Closed it will be about 3m overall length and fully extended it will be about 5.5m overall length. Does anyone know if there is any reason why I might not be able to build one under UK legislation? It will need brakes and I am working on how to do that with an extending pole and the pole will need to be strong enough to take the loading. With it extended I will need to keep to the maximum nose weight of 60kg on the hitch when loaded. Thank you, NT

Thing is, there are so many factors involved with aerodynamics and with fuel consumption that some rough drawings and generalisations would, in reality, be meaningless. My car does 65+mpg on a 120 mile run if I ignore the speed and drive for economy. If I drive steadily at 60mph I only get 50mpg. My 6x6 weighed over 3 ton, had loads of transmission drag and only 96bhp and it was happy at 80mph at 2500rpm. The torque there was around 190lb-ft.

The truck cab presents an addition 'frontal area' by way of the inside of the tailgate. So not only do you get the grille, wings and cab pushing air out of the way but you get the tailgate doing it as well. You then get drag at the back of the cab and the back of the tailgate. This is why curtainsider trucks keep their curtains closed even when running empty.

Ever seen the old hotrods of the 60's and 70's? They had bonnet scoops to force air into the carbs. The forward facing ones hoped to catch the ram air effect of the forward motion of the car and the rear facing ones took advantage of the eddie currents at the base of the windscreen. The ones facing backwards worked well when there was a windscreen and a normal height roof line relative to the bonnet. The forward facing ones worked when the windscreen and roof were low or non existent and there was a lot of engine relative to the body work. This is also why on normal road cars the fresh air vents are located here and not at the nose of the car.

I think you will struggle with runners that length. How about making your own? A simple way would be to fix a 25mm angle to the bottom of the wheel boxes so that it forms a channel with the floor. Then make your drawer to fit between the flange of the angle that sticks out and then bolt little roller bearing to the sides of the drawer frame to run between the floor and the angle. Cheap bearings can be found on Ebay if you search for skate board bearings, about £2 for a set of 8 at 20mm diameter and 8mm wide with an 8mm bore. It will mean that you can't pull out the full length but if you wanted to do that then you could slide in a shelf under the drawer that is held in place with angle on the wheel boxes. You can then pull out the shelf half way and then the drawer above it almost all the way with the shelf taking a lot of the weight.

From a top view you can see where the green areas of low pressure are, at the back, at each side window and the sides of the front wings. The windows are worse then the front wings as the corners are sharper.

The ribs wouldn't have that much effect in reality. To reduce the suction at the rear you would need to taper the whole body to produce a smaller back surface area for the turbulance to suck on. You don't want to break up the flow until it reaches the rear end. You wnat smooth flow over the body but at the back, if you have a small area, you then want the flow to detach as quickly as possible. That is what the little lip spoiler is for on sports cars.

If it had spare wheel on the back door then it would be. Much of the areodynamic drag from a Defender is due to the blunt back end causing a low pressure area that literally sucks the vehicle backwards against its forward motion. Length compensates for this somewhat so a 130 would be better then a 110 which would be better then a 90.

??? When I last did fluid dynamics there was only one computer on the Uni campus and we had to buy time on it. We also had to write all the programmes ourselves in ForTran and hope that it worked. Most of the calculations were done by hand using simple calculators and log tables.

Ahh, cheers for that. It had me stumped for ages.