Apr 302013

The building of the two 5 leaf spring packs for the boot hinges leaf by leaf was difficult enough, so I wasn’t looking forward to prospect of trying to open up the full five leaves to extend from the mounting point over the receiving pillar on the boot lid arm.

My first attempt was to clamp the hinge unit in a vice, mount the spring pack on the hinge and use pliers to try to open the springs. It was a huge difference between extending a single leaf and the full spring pack! The problem I found was to get sufficient clamping needed to secure the hinge in the vice to withstand the forces needed to open up the springs. Often the hinge would move in the vice in preference to spring opening and, once the paint finish started to show signs of distress, I gave up.

After a few further searches I found an alternative method where the hinge pivot bolt is removed. The spring is mounted to the bracket half of the hinge and the receiving pillar on the hinge arm positioned in the centre of the spring pack. The idea being that the latter could be used to extend the spring pack to a point where the pivot bolt could be replaced. Again all this achieved was to further damage the paint.

Like most problematic issues encountered, I put it off to have a ponder how best to tackle it. Recently someone posted a video on the internet of a rather wacky, counterintuitive way of tackling the problem. I’d not had much joy with the accepted methods so I thought I’d give it a whirl. Nothing ventured, nothing gained.

The hinge was securely screwed to an old 4×2 wooden frame I’d lying around as I still haven’t got round to mounting my vice on a workbench. Essentially the building of the spring pack, covered previously, has simply arranged the leaves in order on the mounting bolt so the spring pack can be fitted onto the hinge bracket.

Inserting the bolt was very fiddly

The individual leaves are then pulled out from the spring pack with pliers, working out from the inner most leaf. The leaf being pulled clear pivots on the mounting bolt and is then extended and placed over the receiving pillar. The process is then repeated for the remaining leaves.

The securing nut on the spring pack bolt only needs to be put on a couple of turns to allow the leaves to pivot. Pulling out the individual leaves with pliers was quite difficult but obviously gets sequentially easier.

I had to use a screw driver to lift each spring to be able to get some strong pliers sufficiently on to the leaf to pull it out. Once a leaf has been partially pulled out, it was occasionally necessary to tease it out further using a screwdriver. The leaf can then be extended using some thick protective gloves and pliers.

1st leaf on! Next leaf pulled out Extending the leaf

I would thoroughly recommend this approach over trying to extend the full 5 leaf spring pack.

 Posted by at 7:03 pm
Apr 122013

The separate wiring loom for the starter solenoid relay was sent off to Autosparks so they could have a look and use it as a pattern to make up a new loom.

In the meantime, I’d posted my wiring dilemma on the E-Type forum to see if others could shed light on the relay wiring. A fellow S2 owner kindly pointed out that there was a change to this area of the wiring during the S2 production run. As it happens, at exactly the same time my car was passing through the factory. I guess that it hadn’t been reflected in the service manuals because the modification had been made mid-production run.

Around the end of ’69, a ballast resistor was introduced into the ignition circuit with the aim of improving cold starting. The original 3 ohm coil was replaced by a ballast resistor and coil wired in series, both being around 1.5 ohms. When the ignition switch is turned to start the engine, the starter relay activates, delivering power to the starter solenoid but also bypassing the ballast resistor.

Therefore when starting, the full 12 volts is applied to the coil. The spark energy is increased over the original setup as the current flowing into the coil is greater due to the lower coil resistance.

Once running, the ballast resistor is introduced back into the circuit. As the coil and ballast resistor have a similar impedance of around 1.5 ohms, the voltage drop across each is roughly the same. Therefore a voltage of 6v is applied to the coil during normal running.

I found the wiring diagram above on one of the American Jaguar sites which shows the wiring connections for ballasted cars. Autosparks also confirmed that they stock this ‘ballast resistor’ loom. Although I think I’ll get the car running before I cut and tape the unused wires in the main loom!

It was a good opportunity to get Autosparks to make up the additional wiring, using the correct colour coding, that I needed for the few upgrades I’d planned – the mechanical brake light switch to supplement the hydraulic switch and the boot light.

There was also a number of wires that I believe are missing from the sundries wiring pack, such as earthing wires for the rear light clusters and a beefier jumper wire between the two brown fuses. Touch wood, I’ve now got everything to complete the wiring.

Alas, it was again a case of one step forward and two back. Very early on in the work on the bodyshell, the LH outer pedal side panel had been replaced where the main loom comes out behind the voltage regulator bracket. The panel was from one of the main suppliers of panels so I foolishly assumed it would be spot on.

It was only once I came to fit the voltage regulator bracket that I found out that its mounting holes had been punched in the wrong place. They were about 5-6mm too close to the sill closing panel so that the bracket doesn’t fit. The bracket did change for the S2 cars so it might be that the panel also changed and I was supplied the wrong part.

Either way – not happy! I should have checked it well before it had reached the paint shop. It’s not the end of the world but it will always niggle me as I’ll know it’s not correct on the car. The annoying thing was I’d spent ages sourcing and refurbishing a replacement bracket, as the studs on the original had all sheared trying to remove it.

The first replacement was purchased from SNG but the fitting was incorrect, using bolts rather than attached studs. Some time later, I managed to get a rather tatty one on eBay which was covered in a mixture of black and green paint. It took several applications of Nitromors and wire brushing before it was good enough to be re-plated.

The problem I find with zinc plating is it’s too blingy (although I’m sure the brightness would dull slightly once exposed to the elements). I decided to experiment and sprayed it with a two-pack clear satin lacquer. The results were even better than I had hoped/expected. The satin finish obviously tones down the brightness but it also has a softer, smoother to the touch feel and a more uniform metallic finish.

After all that effort I didn’t really want to start butchering a perfectly good original part to fit. instead I planned to trim the original bracket to fit and then repair the welded studs but SNG Barratt now supply the brackets with the correct studs relatively cheaply. So I’ll adapt one of their repro parts rather than an original part.

I think I’ll also spray most of the plated parts in the engine bay with the clear satin lacquer. Hopefully it will also provide a more durable finish.

Apr 012013

The benefit of having the chassis on axle trolleys is that it can be rolled out into the open to provide much better access as well as natural light. So the car has been wheeled in an out at every opportunity, weather permitting. So much so that I’d become rather blasé about moving it around.

The Easter weekend gave an excellent chance to make some more progress with the wiring. As I was wheeling it back in for the night, catastrophe nearly struck ….

… stones had worked their way between the ply boards being used as a base creating a much larger step than normal. Not realising what had happened, it was given the usual extra push needed to get the wheels up the step. However the extra height was too great and it almost brought the whole rear end crashing down onto the axle trolleys.

The sooner I can get the car back down on its own wheels the better!!

 Posted by at 9:01 pm
Apr 012013

As I’d spent many days meticulously labelling the new wiring looms using both the service manual and Coventry Auto Components diagrams and all the connections were accounted for, I foolishly assumed everything was correct. All that would remain would be to connect up the looms to each other and the corresponding components.

However I hadn’t checked back to the original loom … until now. The two looms are completely different for the connections to the starter solenoid relay, mounted on the engine bay bulkhead.

The relay connections on the new loom end close to the join between the dash loom and the RHS body loom, circled in Red in the photo. The ends are terminated with female spade connectors suggesting the relay is attached at this point.

However 1) there’s not sufficient length to route into the engine bay and 2) there’s no suitable exit hole near the relay into the engine bay.

So I can’t see how to route the new loom to the relay mounted on the bulkhead.

Where the new loom ends with the relay connectors, the original loom has both the larger current carrying wires for the relay (White/Red and Brown) wires cut, only the switching White/Yellow wire remains. The other end of the brown wire exiting the loom near the ignition switch is similarly cut. As both cut ends appear to be properly taped it could quite possibly be a factory modification, made retrospectively to looms that had already been delivered to Jaguar.

Current carrying wires cut

Brown ignition wire cut

I’ve not located the other end of the White/Red wire yet due to a slight mishap with a Stanley knife while cutting away the taping on the old loom. I’ve found the braided wires to be quite absorbent and the claret colour of blood does a splendid job at hiding the colour coding! Lesson re-learnt: cut away from fleshy bits, not towards!

The relay was connected via its own separate loom, which also appears to be original (right). The routing of the White/Red and Brown wires, cut in the original dash loom, is directly between the bulkhead relay and the starter motor, ie doesn’t enter the dash area.

The switching White/Yellow wire is contained in a spur with sufficient length to reach the dash area from the engine bay via the hole high in the transmission tunnel panel.

So my current thinking is that this was a factory modification to keep the current carrying wiring away from the dash. Only the relay switching wire carrying a low current is routed into the cabin area.

I suspect this change may have been made during the S2 production run as I’ve not found any of the usual suppliers who sell a separate starter solenoid relay loom. I will have to ask Autosparks to make up a loom based on what remains of the original. The other issue is the original loom had a White/Blue wire connected to a central terminal on the relay. There’s no reference to a White/Blue wire in any of the wiring diagrams so I’m stumped what it is for at this stage.

I’ve subsequently found out that it was a factory modification after all. From chassis number 1R1393, just 28 cars before mine, a ballast resistor was introduced and the relay moved to the engine bay bulkhead.

The starter relay was changed so that it could switch two circuits – delivering power to the starter solenoid and bypassing the ballast resistor. The white/blue wire enable the ballast resistor to be excluded from the circuit on start up, increasing the current delivered to the coil.