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Would cutting a small hole in the frame be crazy talk?
or, you could cut some thread off that insert. that may bring it in enough to get away from the frame. or just a different insert altogether.
the local hydraulic shop prob has something that is a sharper angle and does not stick out as much. NOT this exact fitting but you get the idea!
Another solution would be to fit the correct radiator and avoid the need to bodge other stuff.
When l sourced my aluminium radiator l fitted one without trans cooler end tank and instead fitted a separate trans cooler to the front of condenser.
I'm sending the radiator back for a refund. I finally found someone to do a recore at a more reasonable cost, but it was nearly an hour drive to his shop.
I'm sure you guys have gone through this, but the other recore quotes I got, the minute I told them it was for a Jaguar the price went up to over a grand, plus I didn't get a lot of confidence they knew what they were doing in the first place.
So while I was at this shop he gets a phone call from one of the shops I'd gone to earlier to get a quote, and turns out that anything out of the mainstream or difficult they sub-out to him.
Now regarding the aluminum radiator, if you are still interested in making it work, I think the best solution would be to take it to someone who knows how to weld aluminum properly. They should be able to remove the transmission cooler fittings and the welds holding the cooler in place. Then the cooler could be rotated enough inside the tank for the connectors to point in the proper direction, then have them weld the proper fitting for the existing cooler line flare nut fittings.
You'll still have to sort out the proper banjo bolts and spacing, but that should be doable.
I fully understand the XJS cooling system and cooling systems in general. The XJS V12 is a factory bodge job to get into production that was never sorted out.
Originally Posted by Greg in France
Because the rad is lower than the heads, there is an inherent air bleed difficulty in the installation. One Texas-based poster on here has changed his header tank to the bulkhead (firewall) and fed the system into the heater return, doing away with the radtop stuff completely, with no problems. This is possible because the air can now naturally rise to the cap. I understand that this is the system on the latest X300 V12 saloons as well, but I have never seen it myself.
Because the XJS has an inherent airflow problem into the radiator stack, the cooling is far less effective than it should be given the size of the radiator. This is also, I believe, the principal reason the gap between the oil rad and the water rad gets full of rubbish, as a relative low pressure area builds up there owing to the poor airflow. Anyone who disbelieves this should unbolt their front bumper and take their V12 for a spin. I guarantee the temps will be lower and that the temps will reduce much much faster after a hot stop and restart such as in a traffic jam on the motorway. In aero terms, the installation practically guarantees dirty airflow into the radiators when you want laminar flow (clean air). On a 5.3 HE, moving the horns out of the airflow and the second coil, makes a difference also. I believe the fact that the XJS installation entails inherently poor airflow to the radiator is the main reason the cooling is marginal and has very little surplus capacity if not in perfect shape, and is the reason the bleed system is so important.
I agree and Rob Beere Racing sells V12 racers a special gizmo that fits to the thermostat housings that automatically does just that.
I fully understand the XJS cooling system and cooling systems in general. The XJS V12 is a factory bodge job to get into production that was never sorted out.
The basic V12 cooling system has been in existence since 1973 in the XJ range with only minor changes along the way. My own experience with it started with a series I XJ12 in the late 70's and continues today in an '89 xjrs. I have never had an engine overheating problem in all those years.
It may not be perfect and it does require regular maintenance and certain procedures need to be adhered to, but it does the job until owners try to save a buck by cutting corners.
The basic V12 cooling system has been in existence since 1973 in the XJ range with only minor changes along the way. My own experience with it started with a series I XJ12 in the late 70's and continues today in an '89 xjrs. I have never had an engine overheating problem in all those years.
It may not be perfect and it does require regular maintenance and certain procedures need to be adhered to, but it does the job until owners try to save a buck by cutting corners.
What is the regular maintenance required and procedures that must be adhered to? I am a new XJS owner and don't really understand what I should be doing to maintain the radiator other than flush it?
What is the regular maintenance required and procedures that must be adhered to? I am a new XJS owner and don't really understand what I should be doing to maintain the radiator other than flush it?
Welcome to the elite. There is a book called XJS: Experience in a Book by Kirbert Palm. If you google it you can download it for free. It is a really good plan to read it ALL. You will then have a very good idea of the maintenance requirements of the entire car.
This site has some, or even all, of the most knowledgeable and, more importantly, sensible and experienced XJS owners and maintainers regularly contributing to it, who have been and still are being immensely helpful to me and others. Also they are not scornful of new owners needing help or not understanding a particular point. Any particular problem you come up against lots of help will be at hand.
The cooling system needs to be well maintained on a Jaguar XJS V12 because the engine creates lots of heat, and the air path into the radiator stack is a tribute to the victory of styling requirements over engineering requirements! The most important thing to do if it has not certainly been done in the recent past, is to remove the radiator and clean out the gap between it and the oil cooler and aircon condenser, and the blow out all the debris between those items cooling fins. Inspect the rad very carefully and see if it is clogged up inside, etc etc. If it is, it must be replaced or you will cook the engine.
Depending upon the previous owner's knowledge and dedication, there will be a number of things on the car that you should fix; eg radiator and coolant hoses lots of them, injector loom brittle with heat, plug change, HT lead change, dizzy cap and rotor check, rubber suspension bushes. If your car comes from a salty road winter area, rust can be serious. Once done, the car will be reliable, but will always need careful maintenance, which only you will do properly. The main difficulty with the XJS is NOT the apparent complexity - although when you look under the bonnet for the first time it is very daunting! The main problem is access, in that you have to remove lots of bits to get access to the bit you need to fix! Resign yourself to that, take your time, get the tools, and enjoy the car!
Greg
The system is ridiculously complex with no need for it to be so, and is a hodge podge of solutions for a simple fundamental issue of the radiator being lower than the top of the engine's cooling system and the need to join the coolant outlets of two cylinder heads.
The simple solution Jaguar should've used was a pressurised header tank up high with a simple bleed line from the top of each head.
The radiator is another design flaw, most every other vehicle works quite fine with a simple, single pass radiator and merging the coolant outlets before they reach the radiator. Designs that were well thought out actually do this on the engine with castings, eliminating many weak links and leak points.
As for the XJS having some sort of airflow issue that hampers cooling, rubbish. Why do so many conversions use much, much smaller radiators and never have any of the issues the V12 system has? why do modern vehicles, with much smaller cooling air entry area and much higher output per litre manage to stay cool?
The simple answer is the system is far too complex when there are much simpler solutions.
Using "regular maintenance" as an excuse for the system requiring constant attention, maintenance and replacement parts due to the myriad failure points designed into it is not a valid argument.
The sign of a mature, well engineered design is simplicity and minimal failure points.
Your statement about the V12 cooling system being the same for so long says it all.
Originally Posted by baxtor
The basic V12 cooling system has been in existence since 1973 in the XJ range with only minor changes along the way. My own experience with it started with a series I XJ12 in the late 70's and continues today in an '89 xjrs. I have never had an engine overheating problem in all those years.
It may not be perfect and it does require regular maintenance and certain procedures need to be adhered to, but it does the job until owners try to save a buck by cutting corners.
Using "regular maintenance" as an excuse for the system requiring constant attention,
No, not really. I think you're getting a little caught up in your own ballyhooing. You'd make a good political commentator
Experiences vary quite a bit.
My experience is to go thru the cooling system complete, do it once, do it all, make it right....and forget about for years. Except the every 2-3 year coolant change, of course
My gripe is that the system doesn't seem to have enough capacity for very hot ambient conditions, ie; Las Vegas in August
The system is ridiculously complex with no need for it to be so, and is a hodge podge of solutions for a simple fundamental issue of the radiator being lower than the top of the engine's cooling system and the need to join the coolant outlets of two cylinder heads.
The simple solution Jaguar should've used was a pressurised header tank up high with a simple bleed line from the top of each head.
The radiator is another design flaw, most every other vehicle works quite fine with a simple, single pass radiator and merging the coolant outlets before they reach the radiator. Designs that were well thought out actually do this on the engine with castings, eliminating many weak links and leak points.
As for the XJS having some sort of airflow issue that hampers cooling, rubbish. Why do so many conversions use much, much smaller radiators and never have any of the issues the V12 system has? why do modern vehicles, with much smaller cooling air entry area and much higher output per litre manage to stay cool?
The simple answer is the system is far too complex when there are much simpler solutions.
Using "regular maintenance" as an excuse for the system requiring constant attention, maintenance and replacement parts due to the myriad failure points designed into it is not a valid argument.
The sign of a mature, well engineered design is simplicity and minimal failure points.
Your statement about the V12 cooling system being the same for so long says it all.
You should not use part of my statement out of context. I also stated l had never in those 35 odd years had a cooling system problem, that might indicate it was doing it's job.
[QUOTE=Typhoon;1319060]
As for the XJS having some sort of airflow issue that hampers cooling, rubbish. Why do so many conversions use much, much smaller radiators and never have any of the issues the V12 system has? why do modern vehicles, with much smaller cooling air entry area and much higher output per litre manage to stay cool?/QUOTE]
I do disagree with your point that the XJS does not have an airflow issue. It does, both getting air through the radiator and out of the engine bay. This has been demonstrated very clearly, and dealing with getting hot air out of the engine bay was a big factor to be overcome in the TWR racing XJSs, as was well documented by Allan Scott, the TWR engine builder and designer, in his book on the subject. It is also the reason why the Series 1, 2 and 3 XJ saloons with a far less cramped installation of the same engine and an identical cooling system, except for the air path into and out of the engine bay, do not suffer from this problem to anything like the extent that the XJS does.
Engines with higher specific outputs generate less waste heat than the v12, because their fuel is producing more motion, and less heat. Modern cars have very efficient air paths into their radiators and out of their engine bays and a great deal of attention is paid to these aspects by their designers, for a number of reasons including aerodynamic drag reduction. Additionally, modern radiators are better transferers of heat than those of the XJS era.
Your criticism of the complexity of the XJS cooling system is one thing, maintaining that when functioning properly this complexity causes the radiator matrix to transfer heat to the air from the water less efficiently is quite another, and is patently not true. After all, as the water pump is pushing coolant through the radiator, what other explanation can you give for why the water is not getting sufficiently cooled in the process?
Last edited by Greg in France; 10-01-2015 at 02:57 AM.
Is it all 'Tig Welded' or has the Core been glued in with Epoxy.
BTW, I think I can explain the price difference on these between the UK and the US. After corresponding with the seller, I noticed that the timing of replies are consistent with them being based in the UK, and eBay listed them as being in the UK. Plus when they gave me the ship to address for the return, they referred to it as "our US agent".
So, they are probably bringing them to UK by the container from China, then shipping a portion to the US. So, that doubles the shipping costs, which is probably the highest single cost in the unit.
Your observation seems spot on, as it looks like they are Imported to a Central Clearing House in the UK, where various sellers all seem to obtain their supplies and then drop ship them to various parts of the World.
From what I can tell most of these Sellers dispatch from a Warehouse in Portsmouth (UK)
With those kind of prices it does seem a shame that there seems to be problems, in trying to fit one in an XJS, as they are less than half the Price of a New OEM.
If only they had fitted Screw Connectors for the 'Tranny Pipes' then it may well have been a different story.
Sorry it didn't work for you, as I was very tempted to order one myself.
what I really do not understand is the fact that the radiator for the 'up to 87' is much cheaper than the radiator for the 91.
the only difference I can see is the tank is on an angle. some slight differences.
do these differences really require an extra $200. is it that much more labor intensive or requiring that much more material. most other cars (including corvette v8) from the same manufacturer are around $150.
what I really do not understand is the fact that the radiator for the 'up to 87' is much cheaper than the radiator for the 91.
the only difference I can see is the tank is on an angle. some slight differences.
do these differences really require an extra $200. is it that much more labor intensive or requiring that much more material. most other cars (including corvette v8) from the same manufacturer are around $150.
I give this info Just for some perspective.
I bought and fitted a new aluminium radiator to my car about 12 months ago. Made by a specialist maker with motor racing background here in Australia. Core is a US made unit furnace brazed not epoxied. Very high quality job and perfect fit with all threads as original, BUT it cost me close enough to $1000.00 AUD
If somebody is selling radiators for $150.00 there may be a reason they are cheap.
I am so sorry you ran into these problems...
I just bought one as I purchased my XJS knowing it was a leaky mess...
v12performance provided it but I found they are just a re-seller for WIzardCooling High Performance Jaguar Aluminum Radiators
they do do more than Jaguars
and mine was simply bolt it in... I was concerned that it was thicker, but even with the stock fans it was just bolt in...
Oh that thanks goes out to whom ever point out that my orgl. fan was cracked and not to put it back in... upon closer inspection you were right so I followed your advice and ordered the BLACK fan and now she leaks not and warms up a lot faster...
my MPG has increased... yeah....
Last edited by Jonathan-W; 10-08-2015 at 10:54 AM.
Hey, mine leaked 1.5 gallons / 4mile drive...
never over heated because I always checked the level and topped it off...
never had to burp it when topping off because the holes were at the top of the radiator where the electric fan was... top run and three wonderful little pin holes... 2 would **** through the fan opening... when the radiator was full...
I had to burp the radiator for the first time after putting the non leaky new one in as there was no way for it to self burp...
been 2 weeks now... I will check the coolant level this weekend...
Wish I'd have known of those brass pipe to barb 90 degree fittings when I dd my lump.
I did find straight pipe and flare for trans coolers use. I used my tuboing bender to make them 90's. Look good, work fine.
I did need 90 flare fittings down stream. A friendly parts place let me search their Dorman cabinet. I found them. Plumbing for the in radiator trans cooler works and looks just fine, sans leaks as well.
Almost back on the road with my '88 XJSC. I got one of these pretty ebay radiators six months ago and made my banjo bolt from a stainless bolt by drilling it after careful measurements. My problem come into play with the transmission lines also. Same as the beginning of this thread, fit...pre'87 ... My issue at the moment is learning threads to get the fittings to fit the radiator which is 1/2-20 inverted flare BUT I'm being told that I need AN fittings. There is no adapter for the 5/8-18 o-ring style transmission lines to a 1/2-20 inverted flare to us the existing hoses. Summit racing offered to make the lines for me from the transmission to the radiator using stainless braided hose from the tranny to the rad. Hate having that much rubber involved but don't think I have a lot of choice at the moment.
I couldn't find anyone relatively local to recore my oem radiator at any kind of reasonable price, so I ordered a new aluminum one off FleaBay.
It's a nice looking unit, but it has different threads for the banjo bolt and the height of the radiator where the banjo bolt goes is higher than the oem radiator. The supplier includes two new aluminum banjo bolts with the radiator.
However, the threaded portion fits through the air bleed piping/banjo bolt hole, but the non-threaded shoulder does NOT fit through. Attached is a picture of the banjo bolt and how much higher the hole on the radiator sits, a picture of how the bolt sits in the air bleed porthole, and the air bleed fitting interior.
If I can find the proper sized spacer and copper washers, could I drill the air bleed fitting open enough to accommodate the larger banjo bolt without wrecking the fitting or defeating it's purpose?
Please help, thanks guys.
Find a reamer tool for perfect reaming out the hole.
09-28-2015, 06:20 PM
