So given the excellent information that exists re the cooling of the V12 I still have a number of questions.

In the excellent write ups by Grant it is mentioned to use Ford fan packs -

Q1 : which Ford and how controlled - I don't want simple ON/OFF. - the warnings about of the fan disintegrating are the only reason I'm even thinking about this - I've never had a problem like this.

Q2 : Would owners of such cars present here recommend the 3 row aluminium radiators that seem to be available everywhere - since the block is aluminium I don't think it would be a big deal - would it ? -

The current radiator doesn't seem sludged though, I'm tempted to throw some flush into the cooling system, run it a spell but I don't know if I really want to run it long enough for the flush to do its job just in case - I have no desire to turn the car into a basket case and a destroyed engine followed by a five figure rebuild is just not somewhere I'm in the mood to go.

Q3 : If I am purging the entire cooling system why wouldn't I go to an OAT type coolant which offers much better corrosion protection than the stuff the car had from the factory.

Reading all the fun people have with bleeding air out of these

Q4 : Is there any reason why I shouldn't use my vacuum fill system that I use on more modern systems - doesn't seem logical to impose old school bleeding tricks whilst I have that in the toolbox

I want to recommission the cooling system in the best way possible but I also don't want to be burning funds needlessly - there are deep pockets and bottomless pockets, I do not have the latter ...

 

Experiences with the aluminum radiators are all over the board. And the quality of said units seems to be all over the board as well. I've never used one, as the original design always worked fine for me. But, others will chime in with some feedback based on first hand experience


With a V12 especially, "doesn't seem sludged" ain't good enough

The radiator (and the rest of the cooling system) has to be 100%. At 97% you'll have all sorts of woe and misery

Cheers
DD

 

I see no good reason, off hand, to avoid giving it a try! Report back, please.

Of course, avoiding the mess, misery, and bother of bleeding doesn't garner any "Jagman" points but some people place more importance on that than others

Cheers
DD

 

I bought an inexpensive vacuum fill system. It works well on the XJS and other cars I have.

 

Ben,

1) I used the 1996 Ford Falcon (Aussie car) Taxi Spec fan pack. The latest and greatest back in 1996, when I did it. These days there are very few cars with engine driven fans, so the choice is much better than I had. The Ford fans slid in, as I said, and that surprised me, but a bonus is a bonus. Greg in France will chime is with his useage, when he wakes up.
They are controlled by relays. and the Thermo fan, RH, is switched by the Factory switch already present in the water pump Inlet, and ours is 85C.
The LH, is A/C only.
Thermo fans are a waste of time is the cooling system is not 100% as Doug already said, and that, I cannot stress enough.

2) Never had the dis-pleasure. Others have, and that is fine. The factory radiator is just fine, and as I said, we get 45+C Summers., and no issues at all.

3) No reason at all.

4) Never used one. I have never really had issues bleeding a V12, as long as you fill it SLOWLY.

The cooling system is the most neglected on these cars, basically from fear of PO,a nd caretakers. Take the time, sort the radiator, and a factory style recore is fine, flush all the system, many times, heater core, engine block, then do it again. Do the banjo mod, clean out the metal header tank and the hidden overflow tank. Last one I did, years ago, took a week, and that was in a MESS.

 

It is very unlikely that you will entirely purge the system, and IAT and OAT type coolants sometimes don't play nice together. Generally, you're better off using what has been used since the car left the factory, and today's IAT products are significantly better.

The OAT coolants were advertised as "lifetime", but remember that a car's lifetime is defined as "the warranty plus a day" not how long a classic will last.

 

Recore'ing the OEM rad is more than sufficient provided the rest is up to spec.

There is an entire Saga on thermostats that many here will go on at length about, and rightly so because the wrong Tstats will defeat any other improvements right off the bat.

I used MetalRescue (ph neutral rust converter) which suspends rust as a black silt - coolant filter helps here. A professional flush or even using a wet shopvac to violently suction things is a good step, you'll be amazed the crud you pull out.

I use mostly water and some CAT ELC (industrial grade) coolant or other ec1 spec semi truck stuff which is good for a million miles...just dont mix brands it becomes a slime in the system.

 

I already have a full compliment of hoses although I'm now considering getting the same but in silicon, I've ordered a pair of Gates 33188S thermostats - I posted some of my 'stuff'' perhaps inapporpriately in the welcome forum and replicated it below, I do plan to pulll the radiator out, and do all recommended mods, I will be painting that bleed pipe, ensuring that it is cleart, the other metal pipes I will also attempt to inspect internally and clean up manually or replace if needed.

I do intend to pop the block drains out (assuming I find them) and assuming that they aren't corroded in place (if they are there is no hope for them because they will strip the block thread when you remove - judgement call). I have experience with aluminium blocks where anticorrosive coolant hasn't been deployed or a car has sat for extended periods with no coolant movement or changes and it is all bad.

The aluminium returns to nature and clogs things up, it creates a kind of sand, based on that experience there is nothing a flush will do to shift the 'sand', sure you get the rust out but nothing will shift the sandy substance - the only real way to clear it is to dismantle and pull the liners - then be prepared to cry as you see how badly pitted the aluminium is (I've had blocks go porous because of it - good luck finding that leak !!) - cathodic / galvanic corrosion caused by disimilar metals - it is a protection method used to protect ships - the least noble metal is sacrificed (usually zinc) but this protects the higher noble metal - steel.

Thermostats for the XJS I've already had to buy from the USA .... £20 each here, £4.95 each in the USA ... (Gates 33188S) ... applied Grant's advice. Unfortunately the Stralian suppliers are pretty creative when it comes to shipping, like not combining shipping and charging per item, this may not sound like an issue but when HMRC charge tax even on shipping costs it can make things stupidly expensive. I also found a site describing a similar issue on E-Types and it has a neat table at the end for those trying to identify alternatives, it also reviews consistency and standards of various suppliers E-Type V12 - Thermostat assessment

I shall at some point be ordering two of all service spares for the shelf - and any other 'future' needs such as door seals, hoses, window rubbers and anything else that is obsolete and necessary for function - I can't buy donor cars as I always end up fixing them - I just don't have it in me to harm cats of any kind - including furry ones.

 

Ben,

The gathering of "stock" is getting important now. Greg and I were discussing this the other night on the Batphone, the parts that are going NLA is scary.

Our Aussie suppliers are "special" for sure. Even local parts are bound to come separated, an dfor no good reason.

SNG UK have always looked after me well, Simon is my usual contact.

 

As the Great XJS Prophet of the Southern Cross predicted, I set out my experience:
First, for absolute trouble free cooling the OEM setup, once right will be the easiest option. "Once right" means:

• Rebuilt rad
• New fan clutch
• New hoses (all 14)
• New thermostats
• Replace OEM electric fan with a more modern SPAL fan
• Aircon up to scratch, new condenser and dryer, interior controls working properly.
• Maybe replacement water pump, but you should not need it.
• New drive belts throughout
• ensure the electric fan is wired to always come on with the aircon compressor

I have removed the engine driven fan and replaced it with an aftermarket SPAL fan the largest I could get. I have a 12 inch diameter (replacement for the OEM electric fan) and a 17 inch diameter (for the mechanical OEM) fan, which are a squeeze to get in, 11 and 16 would do. The advantages of doing this are:

• one less drive belt
• far better access in front of the engine
• a noticeable MPG increase
• slightly better more responsive cooling, especially in traffic; but not, repeat not, worth it for that alone; BUT note the point above about replacing the OEM electric with something better.
• noticeably quieter car

The disadvantages are:

• I could never get reliable main electric fan control until Grant explained his method to me and I adopted it. Believe me the V12 EATS aftermarket electronic fan controllers
• I had to build a chassis to hold the electric fans, but they can be mounted in the OEM shroud, but without it access to the front of the engine is far easier. With my system the fans can be removed in about 15 minutes as a unit.
• My main electric fan draws 26 amps and fitting a 115 amp alternator is a must.
• Most aftermarket electric fans are poor quality, SPAL are the best brand you can buy and are used by many OEM makes.
• You need to build and install a wiring loom, relays, fuses, cabin manual control switch, etc.

If you can find a breaker with cars fitted by their manufacturers with electric fans, they will be better quality and cheaper, than 90% of new aftermarket brands. My advice is to get the OEM system working properly and then once everything else if fixed and you need a job to do, look at installing a large electric fan in place of the mechanical one.

 

I can find loads of fans, the VW passat / golf rad pack is almost perfect but it is computer controlled - you can't just throw power at it - I absolutely do not want a fan that is simply On/Off - Silence / huge Noise / Silence / Huge Noise .... I'd kind of like to get the thermostat fully open and keep it there (which is why I went for an 82 degree thermostat not an 88). Based on what I'm finding almost all later fan packs are managed in the same way so I may end up buying a bespoke from KWE, finding anywhere in the North West UK to do a radiator rebuild is challenge.

I do want to remove the engine drive fan for sure - I've done this on everything I've owned that came with such a fan (Landrover, VW Crafter, early Range Rover)

MPG I couldn't give a rodents rectum about - not a very green statement I suppose but anyone that buys a V12 and then complains about economy perhaps made the wrong choice - in fact anyone that thinks running a classic is possible on a limited budget needs a reality check or two - this will start hitting home when parts get rare !!

 

We've had it too easy for too long, compared to many other hobby cars

I'm not so worried about mechanical stuff. But body parts, trim pieces, unique electrical 'stuff'....that's another story.

And I worry that Roger Bywater will someday retire....he's surely overdue by now.....leaving us with nobody to repair ECUs. Which reminds me: I have a good spare that I've been meaning to send for a freshen-up, more sooner than later.

Cheers
DD

 

New radiator ordered - a proper one not an alloy one, water pump also now ('she' would not be impressed) ... I'll recore my old one and put it on the shelf. I still can't figure this electric fan route though.

 

Is it possible to replace the lower radiator hose without removing the radiator and/or fan belts?

 

Yes, but you will curse and contort.

 

Hi Doug... Is this a real thing? I think I have a spare ECU for my XJS... I have worried about what might happen,,, should something happen. This Mr Bywater,,, he can rework an old XJS ECU, and renew it in the sense that one can have a SPARE ECU in the event one fails? Is that so?

 

Hey Ben.... Is there a model year associated with the Passat or Golf you're talking about that fits???? and,,, are you saying that there is no way to bypass all the electronics that would control a variable fan speed to just have it run wide open? I don't care so much about sound... Actually, on the XKR I've been working on, the variable speed gizmo is a cartridge sized box that screws/bolts right into the shroud its self. What's the VW version look like?

 

Yup.

Plus, if desired, he can "Super Enhance" the ECU for better performance. He has done two for me with good results.

Cheers
DD

 

Ben,
Efans have "Power" and "Earth", thats it. It matters not what supplies that power, ECU, Thermo switch, Human Switch, the fan runs at the designed speed. BUT, The ECU fans usually supply power via a controller module ($$$) and they are a stepper of sorts, based on the temp the ECU gathers from the engine etc. Reliable, maybe. My later Jags have this, and it works, so I am not tempting anything, just clean up the earths (here we go again), and dont re-invent the wheel. With the system "spot on" the fan/s rarely come on, fact.

The stats. They are constantly opening and closing, that is their design, and that is why they wear out. If any stat gets to wide open and stays there, it has lost control of the cooling system it is supposed to control.

As I said, my Efans rarely come on, and when they do, they are NOT noisy. My sons Commodore (Google) V6 S/Charged has a NOISY fan, and that is how it came from GM, the Daughters EVO (hack car) is noisier, so I see no issues with the V12 set up I have. If you want a "mud map" of how I wired mine, ask, it is somewhere here on the laptop., or I draw another, simple.

Fuel usage, I encourage alternative fuels (HAHAHA), BUY ANOTHER V12.

I need a coffee, with add ons.

EDIT:

This Doco might help a tad, over and above the "sticky: at the top. A lot of this you already know, and some you will not need, or do.

 

Agred.

I needed an exterior mirror cover the 2010 X Type. NLA.

A spare shed, just for the stash in paramount if you want to "keep" the Jag, any model and year.