After inspecting the fan I noticed a few hairline cracks so I decided to change the fan, fan clutch, drive belt and pressure tested the cooling system. Took her for a little ride and put her back in the garage.

 

Very nice. Is there an argument to be made to switching to an electric fan? It's on my mind for my future baby. Modernizing and improving is a good thing I would think.

 

There isn't.

Modern, high RPM, super effecient cars with sturdy alternators need electric fans. Older cars like the XJS with marginal wiring, older alternator technology and smaller condensers often cant handle the sustained and momentary high draw of electric fans. Adding electric fans without other foundational changes will lead to a less reliable car over all with worse performing A/C.

 

Nice work!
apart from siezed bolts (hence torch) was it straightforward?

 

extremely easy.

 

never gave much thought to it the factory set up cools just fine.

 

There's a tradeoff to electrical fans.

Mechanical fans are fool proof. Work all the time. Even when the clutch fails, it will fail slowly, over a long period of time, giving you months to spot a slowly rising coolant gauge needle to indicate something is afoot.

Electrical fans can fail, and when they do, it's instantaneous. Something in the circuit, whether its a connection, a transformer, most anything, can cause it to immediately fail and you'd never know it unless you noticed your gauge moving up.

I'm sure you're aware of the pros to electric fans, you just have to decide whether that's worth the effort. Personally, I like the foolproof option.

 

Having done an (experimental) Electric Fan Conversion on my 1990 XJS V12 using the Twin Fan Set-up from an XJ40

I took it out and then went back to a Mechanical Fan, as not only did my Car sound like a Sewing Machine but if you're idling in Traffic it can run your Battery down, regardless of the Output of your Alternator

As icsamerica says, if you're using a Mechanical Fan, there is a lot less too go wrong and in the event that that it does go wrong it usually happens quite Slowly, as was mentioned by Vee and so that can give you plenty of time to get yourself a New Fan Clutch and also a New Fan if you should need one

 

Glad I asked lol. I do like cars to remain stock so this will save money in the future. Thanks.

 

I do not disagree with the reliability point (as long as you carry a spare belt and tools)!. However there are points to place in the balance in favour of electric fans too:

• slightly better MPG
• far better traffic cooling (which is why I changed to electric fans).
• noticeably quieter
• better front of engine access.

The key points are

• to buy SPAL fans (or other equally good quality ones) and have the two biggest you can fit (one 12 inch and one 16 inch) and the highest amp draw in those sizes.
• ensure they are mounted close to the radiator and securely so
• ensure the large one comes on automatically on temp rise and also has a separate manual cabin switched relay circuit
• ensure the smaller one comes on with the aircon
• ensure the wiring is top notch and use 70 amp relays.
• ensure you have a 120 amp alternator.

Under these circumstances I believe that electric fans will be as reliable as new-car ones are.