Has anybody fit an electric fan in a AJ16 XJS to replace the Clutch driven one?

If I do this I would want it to fit in the original shroud. If anyone has done this, how did you wire it? How large a fan can fit in that cowl?

Thanks!

 

Mark
Unles you really want to for OEM-look reasons, there is no need to keep the shroud as all electric fans come with their own moulded outers, which are, in effect a shroud that prevents air recirculation. Dumping the shroud also allows the biggest possible diameter fans to be mounted very close to the rad, which is a big plus for effective airflow. If the shroud is kept, 11 inch and 16 inch fans are the size limit. Without it 12 inch and 17 inch are possible, maybe not much in it? The only point I would make is that fixing an electric fan into the OEM shroud is not that easy to do, if the fan is to be as close as possible to the rad. Basically, 1/4 inch from the fins is the best place, with a bit of foam at three point under the fan outer rim to stop it hitting the fins.

I am not a fan of clipping the fans to the rad fins, though lots of people do without any problems. Otherwise rigging up some sort of a fan-supporting chassis has to be done if you do dump the shroud, which can use the OEM shroud fixings.
Greg

 

I would slide outside the square for a minute.

The X300, AJ16, came with twin factory electric fans, and I reckon the radiator of the AJ16 engined XJ-S, and the X300, would be so close as to not count.

The X308, next model up, also has twin thermo fans.

The X300 has the thermo switch in the LH lower corner of the radiator tank, and yes, they run a rather complicated 2 speed arrangement, that really would not be required as a retro to another model.

A simple ON with a/c ON, and the the thermo switch for non a/c times.

 

The fan blade is identical in all XJSs, so the shroud opening size must be close to the V12's one. At least it will accept a 16" fan, but I doubt 17" or more.

The X300/X308 fans are the same, and the shroud is too square to use in XJS.
Of course they are powerful enough, but it would be PIA to installing them.

Wiring is really simple.
When you decide what fan to use please let me know, I can draw a simple diagram for you.

 

Thanks for you replies.

If I would do this, I would want this:

A1 Electric Online Store: Spal 30102803HO 16" High Output Fan

And I would definitely want the OEM cowl in place

Would this entail removing some of the existing mechanicals for the clutch fan?

I also understand that there are some guys who think that the clutch driven fan is more efficient.

Decisions, decisions!

 

HA, decisions are simple, open teh FRESH JD, sit back, ENJOY the moment, and all will be as clear as mud in no time.

This attached write up I did some time ago, so I would NOT forget, goes thru teh basics of what you want to do sort off. I went a tad further, coz I can, and our summers are HOT.

If something is unclear, simply ask, as at the moment I do still remember.

Cooling system upgrade.doc

 

Grant, most interesting observation regarding the t'stat bypass not being closed when hot.

Seems like it should be checked on all and make sure a hot stat seals the seat. Have you had any more experiences since or observations of others. Will have to go check mine.

 

Removal of the existing mechanical fan hub etc will depend upon how much clearance there is to get the electric fan into place. If there is enough room without removing it, it can be left there. If it has to go, I do not know what is entailed on the 6 cylinder engine.

That Spal fan 100% good choice. BUT check there is enough depth to get it in place between the engine and the rad. On the V12 this is a big consideration, I do not know about the 6 cylinder engine.

Keeping the cowl is fine, but I think removing it to fit the Spal properly is a must. Mounting the Spal so it is asc close to the rad as ôpssible is all-important to realise the gains. Plus, if you can get a bigger one into the Aux fan hole, that is also a real plus.

Greg

 

Greg, the fan on the 4.0 is mounted on the water pump, not like the V12. In addition, there isn't a aux fan in the engine side, on 4.0 the aux fan is a pusher type and sits in front of the car.

Mark,
If believing in the specs they write, this fan draws too much current(40 amp is crazy)
If you are in a hot area and use AC so often, this fan will be a big load to your alternator, especially in the evening.
Mine is a facelift XJS 5.3 and has a 115amp alternator, and my fan system draws over 30amps numerically at most(main:25-28amp, aux:6-8amp).
Sometimes the voltmeter drops around 12V, which means it starts to draw current from the battery. I do believe the amperage should be under 30amp in total.
Your car has a more powerful 120amp alternator, but yours also has an aux fan which draws 10-12amp at most, so the electric fans draw 40-50amp in a full load, which might drain your battery.

Therefore I am planning to change my system too.
As Greg says, the best option is installing a twin fan setup including a shroud. But if you want to use the original shroud you will have to consider a lot of things.

If you want to use the spal fan, you will definitely need a PWM controller to reduce current usage.
Or you can choose OEM fans from Ford or GM cars.

 

OOPs.

I got that SOOOO wrong.

My apologies for that major brain fade. I need some sleep.

I have replaced soooo many of the V12's with the electrics, and down here the XJ-S is a V12. The 6cyl is rarer than a LHD car.

 

Yep.

That bypass closing is possibly more important than proper bleeding of the system.

I had one here a few days ago, a PreHE, and apparently it had been "everywhere" for hotter than normal running issues.

The receipts totalled waaaay too many $.

When I saw Genuine stats, the light flickered, so out they came, and 38mm fully open was all they gave. That port is 41mm deep.

Fitted 2 of the mentioned stats, new gaskets, bled it out (the preHE is simple to bleed), and sweet as.

That makes #12 sorted to date, and none have reported any issues.