Range Rover P38 Battery isolator

With the foibles of the P38 BeCM, some might argue that the last thing one should do is isolate the electrical supply of the vehicle when its running – however, with the car’s ability to occasionally have electrical fires, and with certain organisations mandating isolators for vehicles to take part (either as marshal/support vehicles or competing vehicles) I decided to try and come up with a solution.

As such, currently in the “under development” phase, we have a cable operated mechanical battery isolator, with the user interface designed to fit to the bonnet independently, or as part of my OIS bonnet net.

I’ve plumped for a mechanical rather than electronic isolator, mostly as electronic ones are quite expensive, but also I was concerned about even more battery drain issues (something to avoid on a ’38!)

I’m also very conscious of the BeCM and its foibles, so have tried to make the isolator with a removable handle, thereby avoiding little toerags turning it off for a "laugh" and causing no end of damage in the process. The handle will lock into the receiver on the bonnet for off road use, so it’s always there when needed, but spends most of it’s time in the cab so I can use it if needed....

The isolator itself is mounted to the drivers side shock absorber turret under the bonnet. I’m struggling finding a switch of decent enough quality, and so far the system isn’t active until this problem is sorted - more news will follow as sourcing and testing progresses!

Range Rover P38 bumpstop extensions

An uplifting experience

With EAS comes many things…comfort, practicality, safety and let’s be honest, a suave sophistication that allows us all to feel a bit special. With EAS also comes complexity, leaks, sporadic reliability and quite often, a questionable definition of the word “level”
My P38 came to me with certain modifications, some thought through a little better than others.
The vehicle was fitted with steel rims, complete with a sizable offset and massive tyre – 285/65 R16
It also had Arnott Gen 3 air bags, which give a 5cm “lift” on the front, and a 9cm “lift” on the rear.
These bags are tapered, and are designed to provide a lower than standard spring rate when extended, and a harder than standard rate when on the road.

The EAS height sensor arm values in the EAS ECU had also been played with, encouraging the EAS to sit higher at each of its positions, thereby ensuring the benefit of the taller air bags was borne out at the axle – approach, departure and ramp break over angles were significantly improved although further work on the arms themselves has improved matters no end.

Of course, certain elements don’t change – the articulation if anything was worse - articulation (in my eyes at least) is limited by either the axle/suspension geometry, or the contact point between the tyre and the body – the larger than standard wheel tyre combination hindered the full articulation potential of the car (and still does for now – I’m still pondering this problem – more as soon as ideas gel!)

The biggest weakness of the wheel tyre combination however was the bump stops.
When the EAS has an issue, there is the potential for the system to drop onto the bump stops and go into “hard fault”.
The system is relatively simple to fault find and not too technical to fix, so this alledged unreliability is not a big issue for me – I bought some hardware and software from Blackbox Solutions when I bought the car, so I can talk to the EAS, so in theory, as long as I can get the car home, I can fault find, repair and reset everything….but I do need to get it home.
In hard fault on the bump stops, Land Rover say you can drive the vehicle quite safely at 35mph, in fact they thoughtfully have the EAS remind the driver through the dashboard message centre with a not at all annoying “beep” and a “35mph max” message – the bump stops are a telescopic variable rate polymer, and although the ride may be a little harsh, they do enough.

All this works beautifully unless your car is running oversize rubber. What happens in this instance is the EAS will drop to the bump stops, but the rubber on the tyre will strike the wheel arch before the chassis has sat all the way down. 
In motion it acts as a very quick and effective (if somewhat dangerous) braking system, which draws the car to an abrupt halt, tearing bits of body and chunks of tyre in the process. At standstill, it forms an excellent 4 wheel “handbrake” and the wings slowly fold under the strain of the excess weight – the car, of course is un-movable (to the point it won’t load onto a recovery truck) ….not at all good, and certainly little chance of getting it home to sort the initial problem.

I was lucky – mine had an issue on the drive, but nonetheless, I still had to jack it back up and get some chunks of wood between the bump stop and the axle to take the strain of the wings, luckily all done before permanent damage had occurred.

Sorting the fault was no problem – it turned out to be the N/S front pipe not seated right in the airbag, a quick trim with a pencil sharpener and a test with some washing up liquid confirmed all was well, and on start-up, up she came, back to normal.

It got me to thinking though, extensions to bump stops might be a good idea.

You can extend the pad on the axle, but it involves a lot of car disassembly, and potentially welding - not ideal.
I concentrated on the chassis end, and came up with these little beauties, which fit to the chassis without welding, drilling and so on - a simple idea that now has the wheel safely off the wing when the car is sat all the way down.

Here's the car on it's bump stops - note we now have free wheel movement, and no body to rubber contact....

Range Rover P38 steering/axle guard

When I started this project ’38, almost nothing was available – the market is hardly flooded with gear even today, but you can now buy a steering guard at least.

Most are steel, and add a degree of weight to the un-sprung mass, so in an effort to keep weights down where possible, I manufactured mine from 8mm aluminium with a steel diff guard and steel mountings (all zinc plated for extra corrosion resistance)

Mounted at the front radius arm bush to axle mountings, this guard protects the differential, axle casing, anti-roll bar and the steering arm.

I had to remove the radius arms to fit it, and took the opportunity to change the bushes whilst I had everything apart.

So far, it’s done it’s job.

Range Rover P38 Gearbox guard

This guard system is designed to protect the exposed mid to rear part of the gearbox, including the handbrake mechanism – it is entirely smooth so will not snag in ramp breakover situations, and features ventilation holes to prevent the exhaust system creating excessive underbody heat.

Manufactured from 8mm aluminium with strong zinc plated steel mountings, the guard is easy to remove and re-fit in case maintenance is required to the exhaust or gearbox, and I managed to design it so no drilling of the chassis was needed.

It’s been abused since fitment, and thus far has held up well.

Note – this unit has been developed for the 4.6ltr V8 automatic version of the P38.

Range Rover P38 raised air intake (snorkel)

If anyone tells you this one is easy - it's not!

The venerable '38 does not lend itself well to the addition of a snorkel, and my own fussiness made the project even more difficult - I was not prepared to have pipework running down the wing, and I wanted close fitting raised inlet duct so it blended well with the cars' A pillar.

Here's the result....

 

It took massive effort - I made wooden mock ups, templates and all sorts just to get the route right, and the final fitted snorkel took 16 hours of fabrication, but there's not been any car cutting except the rear corner of the bonnet - I reckon it looks well - I can't see it from the drivers seat (UK car) so it doesn't impede my vision, and it's very snug, so I haven't hit it on anything off road as yet.

The cross sectional area is slightly more than the air box inlet in the inner wing, and the variables in the engine management ECU appear unaffected, so I have to assume the air inlet tract to the engine is fundamentally unimpeded, but we'll keep and eye on the values over time and see if there's any significant impact.

Range Rover P38 Sensor arms - EAS (air suspension)

It may seem obvious, but when longer air springs are fitted, the full benefit can only be realised with extended EAS sensor arms.

I know this as my car came to me with Arnott Gen3 bags, but standard EAS arms - when the axle was fully articulated, the sensors went out of range, knocking the EAS into fault, which then required a plug in to diagnose and clear.

These arms are designed to be fitted directly to the original sensor (both types) and require no modification to the sensor mounts at either the chassis or the axle mountings.

The arms can be adjusted in both horizontal and vertical planes, and are manufactured in 316L stainless steel to ensure they withstand the corrosive attack of road salts and debris.

Thus far (after two years of use) they have been entirely reliable, and the sensors never go "out of range" so we've not needed further plug ins, despite some fairly arduous off road excursions.

Range Rover P38 Bush wires (limb risers)

Somewhere to hang the washing....

After a foray into the undergrowth in my P38 quite early on in our “relationship”, I was lucky not to damage the windscreen as a tree branch came back and hit the screen with quite a “thwack”
The foray was at the old off road course at Billing - for those who know it, the old course runs up and down on a steep bank alongside a stream, and is almost entirely in forest, some of which is fairly dense – trees and the consequential threat to windscreen abound.

So being at Billing, during the show week, it seemed a great idea to buy a set of bush cables.
The problem with buying anything at a Land Rover show is that most decisions are generally made as a result of “shiny accessory syndrome” and as such are on occasions not the wisest bit of shopping.
So when the stall holder told me bush cables weren’t available for a ’38, my head decided on buying Disco 2 ones instead, the little voices inside convincing me that they were almost the same…as it turns out (and not surprisingly) they are not almost the same, in fact they are completely different, and they didn’t fit.

However, once home it became clear that the stall holder was indeed correct, bush cables for ‘38’s do not exist – universal sets that fit to roof racks and bull bars are available, but if your car is fitted with neither, then there seems to be nothing out there, and I was not going to fit a bulbar and/or a roof rack just to mount bush cables – I am not a fan of either.

So, it would appear the self-build route beckoned again. Un-deterred, out came the measuring devices and the sketch pad as there were one or two elements that needed consideration…

Keeping the MOT tester happy.
Stress and loading – the mountings and cable should not damage the car when under load.
If the mounts were fitted to the bonnet, would they impact the alarm system when under tension?
Opening/closing bonnet.

Aesthetics – I quite like the look of a ’38, so I did not want to ruin it.

At the front, the classical clamshell bonnet meant that the only place to mount the cables was, well, exactly there, on the bonnet.
Again in an effort to keep a profile pleasing to the eye, I made the brackets follow two of the edges around the castellation. They’re stainless and painted satin black, with a gasket to seal against the bonnet and stop any chance of corrosion.
For underneath, I made a steel plate fitted with rivet-nuts to spread the load further, and hopefully prevent any chance of distortion.

After some fairly serious abuse, the cables have performed well, with no problems - and when camping, they're great for drying muddy trousers.

Self jack

When carrying gear around in the back of the car, it doesn't take long before the weights mount up, and the space becomes scarce.

With this in mind, if you can design a piece of equipment that will do more than one job, in theory at least, you will reduce the weight you're carrying, and have room in the boot for essentials, like coffee and chocolate.

So, out went the jack pad and instead, in came what I like to call the "OIS Self jack"

The pad serves as a normal base for a HI-LIFT jack, spreading the weight in soggy areas, and providing a more stable footing - all fairly normal. However, with the addition of a single, adjustable arm, the unit changes to a vehicle jack, great for wheel changeing or simple maintenance.

The cup on the arm is placed on the axle tube, and the vehicle then driven or winched forward - the swing action lifts the vehicle as it moves, and then locks in the forward position so the vehicle is then safely at height - you can see a video of it in action here

When jacked, the wheel is around 2 inches clear of the ground, offering me decent height - to lower the car, the locking pin is removed, and the car driven (or winched) backwards

It took a few goes to get the driving technique right, and diff lock with low range engaged is essential, but it gets the car up in a few seconds, and means the bottle jack (which on my P38 is fundamentally useless anyway as the tyres are oversize) no longer has to reside in the boot.

Innovation off road

OIS is a small British based enthusiast designing and engineering solutions not commonly available in the 4x4 accessory market, specialising in bespoke items for vehicles or protocols that may not otherwise be catered for.

It all came about as result of equipment not being easy to source for my own cars, especially in regard to the 2nd generation Range Rover, the P38, for which equipment is historically extremely difficult to source.

The equipment developed may be suitable for business and recreational use alike, and the aim always revolves around deep rooted engineering, ergonomic and aesthetic quality - each product featured in this blog is an example of a solution designed, prototyped and engineered to meet a specific demand - everyone's tastes and requirements differ, but in every instance, I've strived to produce a quality product to my own exacting requirements.

This Blog has been created to demonstrate what can be achieved with very little equipment, but a lot of passion - not everything worked first time, on some occasion’s more than one prototype and test cycle was required to achieve the desired result.

The often asked question "is this equipment for sale" is a tricky one - the original intention as development was carried out was "Yes" - however, tooling costs, the lack of economies of scale and the issue of markings (CE, TUV, BS etc.) combined with potential liabilities and a lack of adequate resource to produce on a commercial scale has prevented the venture from moving beyond its current status of an enthusiastic amateur - now I just make for me (and my mates)