Living with Lady Penelope in the Wild Wild West

[Rok_Dr]

Seeing Dstary’s recent post of starting woe reminds me it’s time for a brief update.

In December we had yet again another reappearance of the cooling fans not kicking in at low speed. I again fitted a new new relay which didn't fix the issue. By now I had a good collection of relays (2 new, the original and the X300 one fitted 3 years ago) and refusing to believe that all were faulty, did some diagnostic digging over the Christmas break.

So out with the electrical circuit diagram and a magnifying glass.

• First checked the fuses which looked good, but changed them just in case. No change.
• Next checked the operation of the radiator thermo switch with a multimeter (earth pin beside the LH air box and positive on the relay plug base and monitoring the temp using an IR thermometer on the top radiator hose. The low temp switch in the sensor closed bang on @86 deg.
• Checked the fan operation by carefully stripping the cover off the original relay, plugging it in and manually activating each relay. Both fans worked in low and high speed.
• Using this relay I then hooked up a 12v battery and checked the relay operation. All clicked as they should and then checked one of the new relays which also clicked away.
• By now I was thinking dirty connectors or a voltage drop and so proceeded to clean what connectors I could easily get to and the earth point with no success.

At this point I had to go back to work and so decided it was time to farm the problem out to my mechanic. A couple of days later it was traced to a burnt/oily connector deeper in the wiring which when repaired, resolved the issue, so fingers crossed that will be the end.

On a more positive note Lady P now has new shoes!

The Bridgestones she was wearing still had a good depth of tread, were evenly worn and had no cracking, but decoding the date stamp in the sidewalls revealed they were over 15 years old! I ended up fitting a set of Michelin Sport Pilot 3 tyres in the original 225/55R16 size.

The change in ride and handling was immediately apparent. The ride is noticeably more compliant, steering a bit lighter and I can get an extra 20kph going round my fast test corner near home. I could have gone faster but the pucker factor kicked in and it was double demerits season here. Previously I would be feeling the old tyres starting to loose grip and squealing at far lower speed.

Cheers

Steve

[donkeyotty]

I had a similar situation when my fans would not cut in. I eventually traced it ( more by luck than judgment ) to the relay wires which had been crushed leaving the outer insulation intact but the copper wires snapped inside. No idea if this happened when it was first built or during servicing but it certainly foxed me for a few months
Good news on the tyres, it shows the amazing difference decent new tyres can make to our cars.

[Rok_Dr]

Well we've just passed 4 years of ownership and another 2,500km travelled, so just shy of 126,000km.

Only event of note was taking Lady P to a local Jaguar track day at Barbagello raceway. I had my learner wheels firmly applied and elected to run with the slow group, mainly comprising MG's. Not surprisingly she was rather ponderous on the tight circuit, but i managed to keep things tidy with no spins, skids or detours.

Maintenance wise again not a lot to report, but last week the air-cond condenser decided to leak so its going to be interesting finding another.

Cheers

Steve

[Rok_Dr]

Well I've finally sorted the Air Con out and can confirm that an X300 Condenser does indeed fit. Original ones for the XJ81 are rarer than rocking horse poo, ditto good quality second hand items and custom builders here in Perth. X300 V12 condenser part Number is MNA7390BA and its still available from Jaguar.

Its slightly slightly smaller than the original XJ81 unit and the top left pipe comes straight out along the side of the airbox rather than exiting to the LHS parallel to the radiator. Nevertheless it bolted straight up and apparently only needed a bit of modification to the sealing around the unit and a slightly smaller gas charge. Rather surprisingly I didn’t need a new hose from the compressor. A slight bend towards the driver’s side for the top LHS condenser pipe and rerouting the existing compressor hose, from under the air box to across the front of the engine was all that was needed! See the following pics.

Crossed fingers it stands the test of time, but on Sunday it worked nicely during a 32 deg day in the Swan Valley.







And finally Lady P at rest yesterday in the Swan Valley. You have to love the Jacarandas at this time of the year.



Cheers

Steve

[naki_k]

Good info Steve. Thanks for sharing.
I think this is the reality now of running an older car now. You have to get creative about parts, to find a solution.
Did you consider having a custom condenser made up? That would have been the other option?

[newyankee]

I had posted an XJ12 repro condenser source in another thread:
https://www.xj40.com/viewtopic.php?f=33&t=998442&p=184981#p184981

No need to go through the hassles of having a custom unit made. This one fits and works.

[Rok_Dr]

I had posted an XJ12 repro condenser source in another thread:
https://www.xj40.com/viewtopic.php?f=33&t=998442&p=184981#p184981

No need to go through the hassles of having a custom unit made. This one fits and works.

A belated thanks for that link. A lot of googling here turned up a number of links on this site but not that one. Useful to know for next time but thankfully the X300 condenser is working very well in the mid 30 deg days we're having here. Plus getting it from the local Jag dealer means warranty support is much less painful than dealing with suppliers on the other side of the world.

Cheers

Steve