1995 Jaguar XJS Where are engine block cooolant drain plugs

Hi jrmandella. You're making this too involved. First let me say I'm not an expert in your specific brand of car, but the maintenance is the same. I'm happy to read you are doing this to take care of your car. There have been some problems with some radiators supplied to various manufacturers that use plastic drain cocks in the radiator tank. There is a rubber o-ring on the end of the plug. Something happens when removing or reinstalling that plug to the sealing surface in the tank. Once that plug is removed, there will be a leak in the form of a drip about twice per minute. We saw so many of those after servicing cars for the winter that we no longer used the drain cocks. Instead, we just disconnected the lower radiator hose. It made it easier to flush the system too. The cause of the leak was inside the tank. A new plug with a new o-ring never fixed it. We replaced a couple dozen radiators one winter for leaking right after the system was flushed.

Instead of hunting for plugs on the block, it is far more effective to just drain the old coolant into a drain pan, then remove the heater hoses from the block and flush water from a garden hose through the system in both directions. Some cars, GMs in particular, have plastic nipples on the heater core that snap off easily. That's why we always removed the hoses from the engine. The main thing you're after is to flush out all of the old coolant because acids build up from combustion gases sneaking in.

The only problem with this method is there will always be some nice clean water left in the heater core and a little in the block that won't drain out. If you premix your new antifreeze and water, the resultant mixture will be too weak due to that remaining water. My solution was to add straight antifreeze and a little water, then run the engine until it had circulated and mixed for a few minutes. Then I checked the freeze point and added water or antifreeze as necessary to the reservoir. It will take a few warm up / cool down cycles for what's in the reservoir to mix in, so wait a few days before double-checking the freeze point and topping off the reservoir.

Caradiodoc

Calm down already. No need to get excited at me for trying to help. Being rude will not get you any further responses from any of the other people who waste their time trying to help. If you don't care to know how us professionals do this common maintenance procedure, why in the world did you ask? Warning you about potential problems would earn me a "thank you" from most people, even if it didn't apply to their car.

Your donation is considered a tip, not a requirement. Isn't it neat that you don't HAVE to pay for an answer? I can't understand what I did to set you off, but I will gladly not accept your donation. I have too many appreciative new friends to try to keep up with already. You need to find a Jaguar site where you will find your experts, then see how far you get. Better yet, visit the dealer and ask a mechanic to tell you how to maintain your car. He will love that. Don't be surprised when he tells you they don't remove block plugs. That is not normal procedure on any brand of car.

You will have to contact the owners of the web site for a refund. I'm just a stupid volunteer. In case you can't make your request known to them, e-mail me directly and I will contact them on your behalf. If you would like to ask a question in the future, be sure to specify you only want to have a conversation with a Jaguar expert, and no one else is worthy. There's no need to ruin anyone else's day. Wouldn't hurt to learn some manners either. You'll get a lot better results.

Caradiodoc
caradiodoc@verizon. Net

I understand your disappointment, but please understand I don't "take" your donation. I have no control over anything that has to do with dollars, so I want to be sure you understand it's the owners of the site you must contact. I don't know what the procedure is because I never tried to do that. That's why I included my personal e-mail address in case the process is confusing.

You can be disappointed or unhappy with my reply, but please don't be angry. That takes the fun out of trying to help people.

Caradiodoc

Hello.

Hope you don't mind me adding 2 pennies worth caradiodoc !

There are NO drain cock for the engine block. You can drain the coolant the way caradiodoc described or you can struggle under the vehicle and pop out the block PLUGS. Buy new plugs and struggle to put them back in place. (Not advisable). The easiest way is to remove radiator bottom hose from under vehicle. It is very easy to do I have done it hundreds of times. Follow the flushing procedure below or caradiodoc's advice !

DRAINING
Remove radiator cap and open heater control valve to maximum heat position. Open drain cocks or remove plugs in bottom of radiator and engine block. In-line engines usually have one plug or drain cock, while "V" type engines have 2, one in each bank of cylinders.

FLUSHING
CAUTION:Some manufacturers use an aluminum and plastic radiator. Flushing solution must be compatible with aluminum.

Radiator
Connect flushing gun to water outlet of radiator. Disconnect water inlet hose. To prevent flooding engine, use a hose connected to radiator inlet. Use air in short bursts to prevent damage to radiator. Continue flushing until water runs clear.

Engine Block
To flush engine, remove thermostat. Connect flushing gun to water outlet of radiator. Use air in short bursts to prevent damage to radiator. Continue flushing until water runs clear.

REFILLING

To prevent air from being trapped in engine block, engine should be running when refilling cooling system. After system is full, continue running engine until thermostat is open, then recheck fill level. Do not overfill system.