My 12 has A/C. I have had the cooling system flushed and I live in Florida. The temperature gauge goes to just beyond normal or about 3/4. Is this normal? Does anyone have any ideas on getting the temp down? I know there are aluminum radiators available, and was wondering if anyone had any experience in this realm and also putting an additional electric fan in front of the radiator? I am running 160 thermostats, and have tried 190's, but that left it at 3/4 all the time.

Submitted by NE52-32043 on Mon, 09/26/2005 - 17:45

Echoing some of Pascal's comments, you need to take a systematic approach to dealing with heat in the V-12 E-type. Do the basics first, then go on to bigger or more complex parts of the system.

1. Check all the hoses and make sure they are in good condition, especially the return hose from the bottom of the radiator to the pump. That bottom hose is the most neglected one on that car, and if it is soft, the suction from the pump will close it down, restricting water flow. Ask me how I know.

2. Next, check the termostats. Make sure they are correct and that the jiggle valve is installed on top (12 o'clock position). You can't just buy any old thermostat at Auto Zone. It has to be the kind with the by-pass cut-off. Don't assume because the stat is new that it works. Check them by dangling them in a pan on the stove with a thermometer to be sure they both open at the correct temperature.

3. Make sure you are running a 50/50 mixture of water (preferably distilled) and anti-freeze, with a bottle of Red Line Water Wetter added. Then check your timing and set and balance the carbs according to the shop manual. A lean running engine can cause serious overheating.

4. Once all that is done, check the running temperature on both sides with an infra-red thermometer. Those gauges in the car are notoriously inaccurate, so you need to know what the actual temps are. It may turn out that your gauge just reads high.

5. If you are still actually running hot, the next two things to consider are the water pump and the radiator. Over time, the water pump impeller car corrode or deteriorate, and you may not be moving enough water. Also, the radiator is marginal, IMHO. I replaced the radiator in my former '72 2+2 with an aluminum radiator from Ron Davis Racing and it made all the difference in the world -- no more overheating. In my opinion, rodding the old radiator or even recoring it are not worth the time, effort or money. I believe that CoolCat Express Corp. (www.coolcatcorp.com) is making them now too. And I think Terry's Jaguar does a water pump rebuild that includes a more efficient impeller.

Hope that helps. Let us know what you find.

Steve Weinstein
'70 XKE FHC
'69 XKE OTS

Submitted by pascal@jcna.com on Mon, 09/19/2005 - 21:47

frank

first, you need to make sure the gauge is accurate... they often are not and maybe your 3/4 is actually the same temperature as my 1/2... an other quick check, don't laugh, is to make sure both fan run and that they run in the same direction! pulling air thru the rad...

i doubt Tstat will make a difference, once it's open, it's open and the issue is the capacity of your cooling system.

is the temperature the same stopped or at speed. If the temp remain the same at 40 or 50mph then adding a pusher fan isn't going to help.

the cooling system on the V12 shouldn't have any problem in so florida. riginally mine had the stock radiator which i had to replace after an accident. I installed an alloy rad from www.classicjaguar.com and the car runs a little cooler, by something like 2 needle width on teh gauge.

maybe your rad is just dirty and clogged up, redcing efficiency.

also, timing may have an effect on temp. and make sure the lower hose doesn't collapse under suction.

i can't say the car runs warmer with the A/C on.. maybe just a little. FWIW, and again gauges are inacurate, i run with the needle on the O of normal at highway speeds, and at the A in traffic.

Pascal Gademer
72 E-type 2+2
00 XKR Coupe