Test fit prep — Power steering upgrade

This post completes the previous post (Test fit prep — front suspension) by describing the process of fitting the power steering upgrade to the front cross member. Originally this description was planned to be part of the previous post, but I decided to split it into two parts as I felt the original was getting a bit long-winded.

Reference Lin Rose’s excellent coverage of this topic:

Being a 2.4-litre, my car was not fitted with power steering. The standard Mk2 steering is based around a Burman F3 recirculating ball type Steering Box where a “nut” (4) runs on a continuous train of steel balls (6) along a worm gear (3), as the worm rotates (via the steering column) the “nut” moves along the worm which then forces the rocker shaft (18) to rotate. This steering system gets a lot of bad press due to supposed vagueness.  My memory (which is also prone to vagueness) is that the standard steering wasn’t all that bad.

Notwithstanding all the above, I decided early on in my restoration to fit power steering to my car as it’s years since I’ve driven a vehicle without power steering and I doubt I would enjoy the experience.

I researched a range of options; including sourcing parts from XJ6 and other Jaguar models, I also had a last minute opportunity to buy a complete front end from a Jaguar 420,  which (I believe) fits straight into a Mk2 and comes with the Marles Varamatic power steering which was introduced in March 1967 on the 3.4, and 3.8 L Mk2s, and in the later Jaguar 340. (Original Mk 1 and Mk 11 by Nigel Thorley)

I decided to purchase a power steering kit from M & C Wilkinson Ltd. The benefit of this approach (to me anyway) is that I get something set up and ready to go, without having to buy parts that will almost certainly need refurbishment. The power steering upgrade will need to be certified by an engineer before the car can be registered for road use here in NZ as it’s a modification, but I’ll cross that bridge when I come to it. At least I’ve made a decision! Additionally, I’m able to benefit from all the hard yards others have put into this topic, namely Lin Rose (link at the top of this post), Richard Oliphant and others in the Jaguar Lovers forums where there is a wealth of information on this conversion.

I found M & C Wilkinson very helpful in all my correspondence with them, I chose the double pulley for the alternator to match the pulley on the 3.4 L engine I’m fitting. This was more of a guess as I’m not sure of the exact cooling options I’ll be going with at this stage. After placing the order the kit arrived into NZ customs within six days. Due to the value, I had to pay GST and some other fees on arrival.

Here are links to the parts list and the fitting instructions for the kit.

After refitting the hubs, with the original bearings (for now), I stripped the front brakes down to the calipers by removing the cylinder blocks, pistons and disk pads. I then fitted the calipers and the tie rod levers to the stub axle carriers.

Next, I fitted the mounting brackets for the power steering rack using the bolts provided in the kit. The brackets bolt to the front cross member where the original steering box and idler fitted.

The instructions state that 10mm is to be removed from each outer tie rod. I carefully measured this and used a hacksaw to remove the required amount from the tie rods. I then fitted the tie rod ends by screwing them all the way in and then backed them off by two full turns, as per the instructions. Actually, this was more like two-and-a-half turns when allowing for the correct orientation of the ends.

Next, I assembled the rubber bushes into the mounts on the steering rack. The final step, for this stage of the process, was to fit the steering rack to the cross member. I found I needed to loosen the bolts on the mounts to allow the rack to fit, re-tightening these bolts was slightly awkward with everything in place, but this was a minor issue.

With the steering rack now attached, the final job was to strip, clean and check the state of the anti-roll bar components. I replaced the washers, bushes, and the two link arms which were both quite badly bent. I also discovered that additional, clearly non-standard, spacers had been fitted under the aluminium packing blocks. I’m not sure what the purpose of these were.

After attaching the anti-roll bar to the cross member both the front and rear suspension units were ready to be loaded onto a trailer and delivered to The Surgery for the test fit. This all turned out to be a bit of a rush (as per normal) which is why there are no pictures of the anti-roll bar fitted. However, here are the front and rear suspension assemblies ready to be attached to the body once more.

This completes this phase of the project, when the front suspension is refitted to the car, we will then fit an alternative steering column, and make the modification to the chassis rail as detailed in the instructions.