The owner needs to ensure the cooling system is purged of air. xxxxxxx

Jaguar radiators block very easily due to the small diameter tube design and due to Jaguar recommending the use of sealers in the coolant. Don't do this! If the previous owner used a sealer you will probably have to rod the radiator. If the owner has overheating problems I suggest you check for debris in front of the radiator prior to rodding the radiator, both of my cars were running hot prior to me removing all the garbage between the radiator and air conditioning exchanger.

If cooling problems persist check the thermostats by boiling water in a pan and check the thermostats open at the correct temperature. The correct specification is 88C (190F). Many owners think using a lower temp thermostat will solve overheating problems, but I can assure you it will NOT. Check the radiator. Running an engine with cooler stats is a poor choice for fuel consumption and engine efficiency.

 

the fan clutch was seized on one of my cars. More cooling at idle but too much cooling at higher rpm's and also absorbs a lot of power from the engine. Either replace the fan clutch or better still fit an electric fan. I have not chosen an electric fan as yet because a want to buy a dual fan with a cowl as one unit that fits a Jag, any ideas?

The Yellow fans crack, both of my cars had this problem. Replace it unless you want to risk major damage under the hood. The replacement is a black fan, see Kirby's book for details.

If a fan shroud is not fitted the cooling fan will not function correctly. Ensure foam is installed between the car body and the radiator.

The front spoiler contributes to the cooling effeciency and vehicle stability. If your spoiler is missing, get a new one. It's expensive! One of my cars does not have a spoiler fitted.
Welsh Jaguar (Tel 1-800-875-5247) now supply a replacement for $180, item BD-45624

 

Only use long life coolant. The cheap stuff sold in the US eats gaskets and can cause severe corrosion. Who wants to change coolant every 12 to 24 months anyway!

Replace them all, the hose only cost a few dollars and may prevent a future overheating problem. Who wants to replace a dropped valve due to overheating! Welsh sells a kit with all radiator and heater hoses for about $100.

If it leaks replace it. If water is leaking you are letting air into the cooling system creating local hot spots. More dropped valve seats!

The heater valve has a poor reliability record due to internal corrosion. Forget the Jaguar replacement, go to Pep Boys and buy a GM substitute for less money and get a better product.