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You are correct, works well in the saloon. If you buy thermostats with jiggle pins ( like the ones Doug mentioned in another thread) then no modification is needed. Fit them as they are.
You have a 1992 Daimler? Very nice, I had a 1992 Jaguar version, made only for Canada and they only made 100 cars. I had #53 /100. These cars already have a Bosch 115A alternator, so you're probably ok there.
Those cars were specially marketed by the Canadian importer, I read on wikipedia. I find the shapes of Jaguars truly beautiful. As elegant, poised and quick as cats ... Anyway, your car seems to be a cousins of mine and built the same year! Why did you sell it?
If you can find it, can you refer to me that car's alternator part number, please?
Why did you sell it? If you can find it, can you refer to me that car's alternator part number, please?
Alternator par number is DAC5224. I sold the car because it was my daily driver at the time, and it wasn't that great in winter. I bought an AWD X Type for the winter and that was much better.
I sold the car because it was my daily driver at the time, and it wasn't that great in winter. I bought an AWD X Type for the winter and that was much better.
I was not aware that Jag went 4WD! I guess that it is progress.
Update. Alicool (below) went upside down but, apparently, the people who incorporated it, came from https://www.radtec.co.uk/ who offer the same assembly, and that's the one that I am going with. Both Radtek and Alicool are located in Cannock (Staffordshire) not far from each other, but are competitors.
Anyway, I am still undecided for the thermostat. Kindly, would someone help and recommend me which of the two (please see below) is better? Please remember that the OEM ones are faulty from the onset and many recommend to NOT used OEM but one of these two that I list.
This is the list of what I will replace:
> Radiator. (Alicool)
> Fans. (SPAL)
> Water pump.
> 2 thermostatic valves (*)
> Hoses (high and low pressure)
> Alternator (*) will be replaced with 110 Amp to power the fans
> Expansion tank
Tommaso, Thank you for the second link. Sorry I missed it first time. I think you have a good plan and have received a lot of good advice. I'm not sure how my system will work as I'm still waiting for the body shop to finish with the sunroof (meanwhile I'm working on my Mk2 - fortunately my other 2 cars actually seem to function, at the moment). The Gates thermostats sound like a good option. Making a small hole in the top is fairly easy - you don't need to treat it as high precision. I favour the lower opening temperature especially with electric fans to give a little margin between opening the stats and switching the fans on and off - no point in running the fans unless the thermostats are full open.
As to what you should see on the temperature gauge: I think yours is like mine with 90°C in the middle and a green range to it's right. My view is the green should be red and if the needle goes in there I slow down (or stop). Our engines aren't fragile (look at their racing record: Le Mans, World Sports Cars, European Touring Cars, SCCA ... In their day, they won everything. A pleasure in the old British sportscars championship was seeing an ancient V12 E type making then current Ferrari F40s look slow.), but don't like being overheated. That applies to pretty well all engines with aluminium blocks. My experience is that the recurring problem has bee blocked radiators. I'd thoroughly flush the engine before installing the new radiator. From then on, keep the coolant 50% anti-freeze. Change the coolant every 2 years, thoroughly flushing the system when you do. Never, ever put Bar's Leaks in the system. If you absolutely feel obliged to use it once, because Jaguar advised it in 1970, leave it in only till the engine warms, then flush the whole system very thoroughly.
The link above is to some interesting work on a an XJ12. He used an electric water pump. I discussed it with him a few years ago and he said it wasn't really necessary, but something he wanted to try.
PS Oil and gas trading must be interesting at the moment.
I have been using the Gates thermostats for several years in an XJS, and they work fine. I'm sure the Stant would be fine too, buy whatever is easier to get.
One of the experienced contributors to the XJS forums carried out some research on the overheating problem. He discovered that he "foot" on the standard thermostat didn't extend far enough to block off the recirculating port when hot. He measured the length required and found the original equipment T/stat was 2mm short, so found an aftermarket thermostat that was the correct length. Unfortunately I cannot find his article, but the new 'stat fixed the overheating problem.
Good evening, Peter, Jagboy and Fred. And, again, thank you all for your precious help. The thermostat choice is important and it seems that both will work.
Peter, regarding keeping the alloy V12 cool, I am replacing the whole assembly, so I should be ok... I only hope that the previous owner did not overheat it! As for O&G trading is... hectic and non-approacheable at the moment! Only big players can afford these risks (volatile prices) so we paused the O&G trades and focused more on other physical commodities as cocoa, coffee, crude palm oil, ground nut oil, etc from West and East Africa.
My Daimler is being repaired in Italy, but I recently moved to Hampshire, England. I am now seeking a Jaguar specialist in the UK. Can anyone recommend a few (more than one, if possible)? I was referred to this one but, alas, he is never available to answer phone calls, or communicate via email.
Tommaso, I've never heard of the one you've been recommended. If you are going as far as Nottingham, I'd use David Marks. He knows as much about that generation of Jaguars as anyone. I go to him. A bit closer to Hampshire are XJ Engineering in Farnham, Surrey, Tom Lenthall near Reading and KWE in Thatcham, Berkshire. Though I've had no personal contact with them, the last three are all well known and respected in Jaguar circles and have good reputations. There used to be someone in Bournemouth, but I can't remember their name or find them on the net. A final suggestion is to join the Jaguar Enthusiasts' Club. Good luck with the move.
I met Chris Knowles, of KWE, in Newbury (Thatcham) last year, after you recommended him.
I can't recommend him enough. He was very helpful, knowledgeable and freely offered excellent advice.
I bought a few small bits and bobs and had my fuel injectors completely overhauled at KWE. His wife made a mistake with the shipping documents, and I ended up paying VAT on my own injectors, being overhauled there, once they went back to Italy. But overall, not a big deal, I loved all the staff and mechanics working there.
... and you should see the cars that he's with on!
The purpose of the jiggle pin is an air bleed. Suppose you have drained the coolant for either a fluid change or thermostat change. Without the pin or hole, when cold the thermostats form a seal and no air or fluid can go past them. If you then fill up the radiator and header tank, you will have lots of liquid in the radiator and relatively little in the block, as the thermostats block the flow of air out of the block. Even if you started the engine, the coolant level will never get high enough to get the thermostats immersed and cause them to open.
Could you show me an image of these bleed holes, please?
I bought 2 OEM thermostats from KWE and Chris Knowles checked that they were opening at the right temperature before shipping them. But I forgot to ask if they had a bleed hole.
I will now ask my mechanic in Italy to check, but he will need an image.
Tommaso, see the little thingy set into the disc at the front top of this photo? This is a jiggle pin (or a hole will do as well). The thermostat, which is fitted with its axis horizontally, must fitted with this pin at the 12 o clock position. I am sure KWE would have supplied the correct ones, but they may have been fitted without the pin being at the top. If he stats have no pin, just drill a 4mm hole in the disc.
Last edited by Greg in France; 12-20-2023 at 12:45 AM.
Thank you, Greg, I just called Dave (at KWE - Knowles), and he confirmed that they sent me 82C thermostats with the "hole". However he was unsure if their thermostats lifted 42/43mm or less. He will check and revert tomorrow.
One point few realize about the Jaguar radiator,
It’s a double pass radiator. Thus forcing the coolant to flow back and forth across the radiator. Thus increasing heat extraction over aluminum or even brass radiators that lack that feature.
It also slows coolant flow in the radiator part while allowing it to move quickly through the engine.
One final point. Assuming good filling/ and other components. If the engine still seems to run hot. Check the engine timing. The distributor is supposed to be regularly oiled. Rarely if ever actually done. Thus the advance weights freeze up and timing gets stuck in the wrong spot.
Don’t just check the timing at an idle , make sure it advances and retards properly.
That green zone is illogical. I've never understood Jaguar's rationale in having it.
The middle on your gauge is 90ºC. Your temperature reading should remain just below the middle in most driving situations. By that I mean about one-needle-width below 90ºC. If your coolant system can't maintain the temperature in most driving conditions then you have a problem that can and should be repaired.
In some driving conditions the temperature might creep up a bit. Climbing a long hill or prolonged driving in heavy city traffic. Maybe a needle-width or two, or a bit more when ambient conditions are over 32ºC or so. This slight increase in temperature is no cause for alarm. It does not indicate impending doom or repairable fault.
Most gauges are marked so that a middle or normal reading occurs at about the point where the thermostat would open. Many, many years ago a notion took hold in the Jag V12 world that any increase in coolant temperature beyond thermostat rating (and thus any movement beyond the middle of the gauge) was overheating. As a result many owners nervously and constantly watched for that movement of the needle....almost like an obsession.
This level of concern is not warranted.
All that being said.....
This ^^^^^ is not good and not normal. Your cooling system has a fault or faults in need of correction. And you're obviously on a path to address the situation.
Cheers
DD
The location of the needle has very little to do with actual temperatures. Water boils at 212 F coolant boils at 240 F. A pressurized system won’t boil until over 250F
As long as coolant is circulating it’s extracting heat.
I understand with all the horror tails you’ve heard about over heating. The reason for your concern. But don’t forget some heat is required. Too cool and the engine won’t boil off acids etc.
07-16-2021, 06:48 AM
