Series 3 Electric Power Steering

Progress has been rather slow. The first thing I need to solve is how to connect the motor to the steering box. The plan is to cut a 5/8" 36 tooth spline on a much shortened steering shaft, I only need a stub sticking out of the steering box, and use a UJ to convert to a 3/4" double D, run a short double D shaft to the next UJ then into the motor which also has a 3/4" double D output shaft. Unfortunately no one seems to make a 5/8 spline to 3/4 double D UJ but I did manage to find a company in the midlands who would assemble me a custom UJ.

Anyway, after a long wait the UJ has finally arrived, price was very reasonable and I had been warned it would be a while.

Next job was working out how to cut the splines. I have a small dividing head and the idea was to hold the worm end of the shaft in the chuck. Two problems here, one the chuck was too small and secondly the outside of the nut dosnt run true to the bearing tracks. The steering shaft was turned true in the lathe and an adapter plate made to take a larger chuck, I took the opportunity to drill in 36 holes into the adapter so I can index in the spline, its very easy to lose concentration when turning the dividing head and be a full turn out so this is a bit of an insurance policy.
Before I commit to cutting the splines into the steering shaft I made a trial one in aluminium to test the spline form and depth.


So far so good, I have a dummy shaft thats a nice snug fit in the new UJ, next job will be the manufacture of the double D shaft and sorting out connecting the series steering wheel to the input shaft of the motor.

Can I just say I love what you're doing here?

I don't quite get the negativity for PAS on Landy's. Yes the steering on a series is fine - if you live on a farm. Living with a 109 in a (European) city, it's bloody heavy. Simple as that.

I have the P38-PAS-parts waiting in the garage, but there's something to be said for a system that does not waste horsepower when it's not used.

Cheers & good luck!

Cheers Barge Pilot, thanks for the support.

Ironically I put a new set of tyres on a few months ago and that made the steering so much lighter.

One of the aims here is to modify the landy so that Miss Kane can drive it, at the moment she finds most of the controls just too heavy. I've installed servo bakes with larger drums and have a larger 8" servo to fit and I've also installed an assisted clutch pedal. When this steering is eventually fitted I'm hoping she will be a lot more confident and willing to drive.

Nice job, thats for taking the time to put it up and inform us all

Citizen Kane said:

Cheers Barge Pilot, thanks for the support.

Ironically I put a new set of tyres on a few months ago and that made the steering so much lighter.

One of the aims here is to modify the landy so that Miss Kane can drive it, at the moment she finds most of the controls just too heavy. I've installed servo bakes with larger drums and have a larger 8" servo to fit and I've also installed an assisted clutch pedal. When this steering is eventually fitted I'm hoping she will be a lot more confident and willing to drive.

Click to expand...

Hi, I'm very interested in your steering conversion. Where are you with it. Is it complete.? Was it a success.?
Regards

Has it really been that long. Not done anything on it over the summer, my attention has been elsewhere. I did manage to buy another steering box, hope this one it a bit better than the last. I've also been assembling other materials, when the weather turns and forces me back inside work will recommence.

I just hope you’ve thought it through. I’m not sure your going to get that lathe in the battery tray.

This has just turned up on ebay for 2500 complete with power steering:
https://www.ebay.co.uk/itm/land-rover-series-2a/153187236101?hash=item23aaabb905:g:N88AAOSwX8FbopOg
Could be one way to get all the parts then retunr it to manual and sell it on. Those 2 Prima engies must be worth something.

Managed to get some time today to pick this up again. I've been pondering where to make the cut on the steering shaft, clearance around the servo is a bit limited. Initially I was going to cut it long so that the UJ would attach behind the servo but his would need an outrigger bearing on the shaft so instead I've cut it as short as possible so the UJ will nearly butt up to the steering box.

Before I could make the cut the outside of the worm needs to be turned so it runs true as this will become my datum for all subsequent operations, once that was done I took the plunge.



No going back now.

Next job is to turn the stub to 5/8" diameter to take a suitable oil seal and the splines.



Last job of the day was cutting the splines.






Need to order up a suitable oil seal and make a bearing retainer plate to house it and thats more of less the steering box end sorted, now I need to sort out grafting the Series column and steering wheel to the motor.

Nice job on the worm shaft. I didn't realise it was as complicated as that. No chance of me doing the conversion.

Col

Steering box end of the conversion more or less complete, I made a couple of new end plates for the box, the top one houses an oil seal. Picture shows it fitted up to my bulkhead mock-up.



Picture showing clearance around the servo.



Clearance looks OK but in reality I think my steering box sits a little higher. When I eventually fit this conversion I want to put on a larger servo from a Defender. To fit the Defender servo onto a Series pedal box requires an adapter plate, next pic shows that clearance is a bit tighter. I can cut back the adapter plate a little more but I think I may need to raise the pedal box a bit as well.

Is there room to raise the pedal box with the larger servo? I have th emid sized (ie largest series) servo and its very tight on the wing and close to the clutch reservoir. I'm looking to go to the bigger Santana /Haystee servo but then I think I will have to notch the wing. Mine had a remote servo under the floor at some time in the past which could be an option. Your work looks amazing.

Fitting a larger servo isnt as straight forward as I had hoped. The standard servo currently fitted to my series and the one shown in the mock-up has a maximum OD of around 8".

The steering box position relative to the bulkhead is set by the bracket that extends down to the chassis, in my case that means the steering box sits high above the foot well which makes clearance around the servo quite tight, the picture of the mock-up is a faithful reproduction of how all these parts sit on my Land Rover.



I was looking at the Santana /Haystee servo as a possible option but just couldnt see how it was going to fit in the available space, I spoke to Haystee about this and they suggested that the column bracket could be rotated to give more clearance but I still dont think this this would provide enough clearance and it would also rotate the ignition switch and steering lock.

I had also read that a Type 50 servo and Defender pedal box could be fitted, the only mod would be a slight re-profiling of the top of the pedal box for bonnet clearance. I'm lead to believe that the Type 50 servo is the same diameter as the Santana /Haystee servo, its max OD is around 9". So I purchased said item and made the mods to the top and shortened the pedal to match the series position and this is what it looks like on the mock-up.



So this looks like a pretty good option, loads of clearance around the steering box area a bigger servo and the Defender box also has a better mechanical advantage as well. The whole assembly sits higher so a wing cut may be needed but nothing to drastic. What no one had mentioned though was how much further forward the assembly sits, hopefully this picture illustrates that.



If you are using a tandem master cylinder your going to need another wing and mud shield cut to accommodate this.

I had also read that the Type 50 servo could be simply adapted to the series servo tower so I picked up another series servo unit the other day to see how easily this could be done, turns out you need a 15mm thick adapter plate to get the operating fork in the correct position and additional machining of the series pedal will be require to interface the two, not exactly straight forward, next picture show me trying to install the larger servo onto the series tower.



Clearly not enough space but you could rotate the column clamp.


OK, just about enough space, if your steering box sat a bit lower (mine sits with 1/2 clearance above the foot well) then your probably alright, I guess I could remove the chassis bracket and slot the 3 holes that bolt to the chassis and lower the box so you may also be able to fit the Santana /Haystee, not sure.

I did think about putting a 1/2"spacer block between the foot well and pedal box but I think it will interfere with the steering box, this may also be the limiting factor in trying to drop the steering box lower. I think I'm going to end up slicing the series box open and welding in a 1/2" strip around to raise it up but I bet I will need a small wing cut then.

So, I've not identified a straight forward bolt on option, the Santana /Haystee may be your best bet but I'm still not a 100% sure you wont need a wing cut and some fiddling with the steering.

I'm coming to the same conclusion, the Haystee/Santana servo is 1" larger dia and I have 1/2" clearance so its going to go to the wire.

Proper project!
But does modifying a component such as the steering require the vehicle to be inspected after completion or affect MOT exemption / insurance cost in any way?

In this risk averse climate I dont yet know what if any repercussion will arise from these mods.

Clearly this system has the ability to deliver more torque but in reality it will mostly be delivering more power so the only concern should really be the heat it could generate, common sense would suggest this wont be a problem.

The amount of torque required to preform and given manoeuvre will remain the same, the only difference with this system is I can do it quicker.

I guess you could argue that I could be operating the steering in a situation where I would not normally be able to provide that amount of torque input to the steering wheel.

Equally its not unusual to see a Series land rover with the wheel arches filled out with larger tyres with increased offset rims or wheel spacer, this must significantly increase the torque required for all manoeuvers, do insurance companies require proof that the existing steering systems are sufficiently robust, I dont know.

Everything from the steering box to the tyres remains stock so the loads should remain comfortably withing design limits.

Despite my intial reservations when you began this thread the quality of your work looks first rate and you are working through each issue and solving it. The things I think that could still turn into issues are:
An accident, bad enough without extra arguments, I would get an engineers report and keep it on file just in case.
The new "substancailly modified" question for tax exemption, this has come from left field and its not really clear what counts as a "yes".
Your system may have a speed input signal, if so you will have options to run with it, put in a manual signal generator or fit a transducer. I would see what the after market systems do and copy them as they have some form of approval (We hope).
There are quite a few series with various power steering systems on so you will not be alone.

Thanks for the input Rob, any idea how I would go about getting an engineers report, would this be as simple as presenting the parts to a local garage and getting an OK from them or is there some king of body that oversees this sort of thing.

I dont think this will mod will effect the tax exemption status or the more recent MOT exemption status, the steering system is essentially unchanged, just an electric motor has been spliced in.

I'm going to buy an off the shelf pulse generator first and see how it goes, but as you say there remains an option for a speed sensitive system if necessary.

I think the qualfications for an engineers report are a bit vague. I've done them for people on here when they are straight forward such as an engine or fuel change and the DVLA have been happy, yours is a bit more complex. Ideally you need a "motor engineers" but when did you last see one of those? You could try a Land Rover specialist and simply pay them for 1 hours work, take your photos, any calcs (more to show you did some than anything) and ask then write a simple letter on company paper confirming it has been done safely. In my expereince offerning to pay for an hour (or 2) is better than asking for a price as people often don't know what to charge and just say no rather than work it out. If you are struggling PM me when the time comes as I'm in Slough and I'm a C.Eng MIMechE. I converted my diesel car to run on cooking oil and got it reclassified as dual fuel, I was aiming to get it exempted the emissions charge (its now sold so I never found out). I wrote my own report but then got the local MOT station to run the emissions test and paid them for 30 mins on their rig. Copy went to the insurers who were happy which got rid of all the potential problems that could cause as it meant I could declare the modifications and get insured with no extra premium.

Got a bit further on with the steering.

I need to fit the top end of the Series column to the EPS unit. To make it slightly easier to get everything lined up I decided to allow for a small amount of angular adjustment. These are the two parts, a flange with the slotted holes and a boss to take the Series outer column tube.



The two parts are welded together, I'm not worried about distortion as all the important machining will be done after all the welding is complete.





The boss in then bored out to fit the column, shown here with the old Corsa one.



Next on the list is the other side of the EPS. The current idea is to fit a tube to the steering box side, this will locate the unit to the foot well, additional metal work will also be required to tie it all into the bulkhead but I still haven't figured out the best way to do that.