I'm getting a "Low Coolant" message on my '98 XK8. Is there a way to know how much coolant I am low? Does the car require a particular type of coolant or can I buy something off-the-shelf and fill it myself?

 

Just search the forums. There are a lot of threads that hold this info. I wouldn't worry as much as how much you are low but more WHY am i low. I am having my 2nd thermostat housing replaced for my " Low Coolant" this week. Have a mechanic check that area. There are a lot of hoses that these cars have to find small leaks in. Best to leave it to someone familiar with your Jag!

 

Usually, you can just refill with water. This is assuming that your anti-freeze protection is enough. You will find that your coolant is either green or orange. The auto parts store can sell you the right stuff.

The coolant should be about an inch and a half below the radiator filler neck. Refill it warm it up and look for leaks. The radiator cap can be bad too. The cap should hold the coolant in.

 

Use distilled water, not tap water, assuming it is just a very few ounces.

 

Here are some info TSBs for you to read.

bob gauff

 

Yeah distilled water won't hurt. Down through the years, there have been a lot of arguements both ways. Supposedly the tap water kills off the anti-corrosion stuff in the anti-freeze.

I used to run the antifreeze recycler at work and here is what I found. The anti-corrosion additives were still pretty good even after being run with tap water.

In rebuilding engines, I would see a film of very slight corrosion, but not a lot. Damage seemed to be most in engines that were part cast iron and part aluminum. The water outlet seemed to get it most.

The biggest damage to cooling systems was from cavitation damage. Air bubbles under compression would hit the cylinder liners and put little holes into the metal. The holes were always in line with the water jacket ports. The overflow coolant recovery tanks were supposed to stop this by taking all the air out of the cooling system. The baffles in the Jag tanks may be trying to do this without having another tank added on.

 

The other concern with tap water is mineral build up in the cooling system, but obviously that depends on the hardness of the water in any particular area.