Coolant leak on 97 Sovereign

Sovereignstuart · Postby **Sovereignstuart** » Wed Dec 04, 2013 7:25 pm

Second post on the forum! It's a 97 four litre sovereign and there is a minor leak spraying over the pulleys at the front of the engine. The reservoir needs topping up with a litre every 1000 miles, or when the warning light comes on. Any advice appreciated.

Regards

Gary220262 · Postby **Gary220262** » Wed Dec 04, 2013 7:47 pm

If yours is a 4,0 V8 this is for you , if its a straight 6 your in wrong place, you need X300 posts

Both water pump and thermostat housing are at the top / front of engine, can you be a little more specific about were its spraying from ?. On the positive both are cheap to replace and easy to fit, thermostat housing should be replaced anyway if you still have the original plastic one for the later metal oneand the plastic impellers on the original water pumps have been known to break up over time (changed mine at 70,000 ish but looked ok when removed) . Just one thing, if your changing thermostat housing you will need a ' Jenner Joggler' but im sure someone will be along later to explain what that is

. Gary

Postby **J44EAG** » Wed Dec 04, 2013 8:01 pm

90 degree bent spanner! Allows you to get to the back two bolts on the thermostat tower without lifting a V8 inlet manifold.

This link details fitting a new tower to a V8 S-type. The procedure is the same for XK and X308 models.

http://www.jec.org.uk/forums/viewtopic.php?f=201&t=4685

Mike k

Sovereignstuart · Postby **Sovereignstuart** » Wed Dec 04, 2013 8:21 pm

If yours is a 4,0 V8 this is for you , if its a straight 6 your in wrong place, you need X300 posts

Both water pump and thermostat housing are at the top / front of engine, can you be a little more specific about were its spraying from ?. On the positive both are cheap to replace and easy to fit, thermostat housing should be replaced anyway if you still have the original plastic one for the later metal oneand the plastic impellers on the original water pumps have been known to break up over time (changed mine at 70,000 ish but looked ok when removed) . Just one thing, if your changing thermostat housing you will need a ' Jenner Joggler' but im sure someone will be along later to explain what that is . Gary

Hi Gary,
It is a 4 litre V8. A LWB Sovereign from 1997. I don't know the mechanics of the car that well, I've got that to look forward too. All I know is that it has been losing a bit of water and the distinctive smell of coolant/ steam was coming off the front pulley set.

Gary220262 · Postby **Gary220262** » Wed Dec 04, 2013 8:41 pm

If your not comfortable with doing the job yourself you could do worse than find a good independant in your area and let him have a look and quote you for the work, im sure someone on here will point you in the direction of one in your area. If your new to the marque you could also attend your local club meet (not my cup of tea but it would help you meet simular minded people) and gain from there no doubt wealth of information. Gary

Sovereignstuart · Postby **Sovereignstuart** » Wed Dec 04, 2013 8:55 pm

Thanks For the advice Gary

I'm not shy of picking up a spanner. Not wishing to blaspheme , but I've mended plenty or two BMC 1100's in my time. There is very little about them I don't know how to fix, or indeed decide to discard. This Jag has landed on my doorstep gratefully. However, II have no idea what to look for, common faults, rust spots etc.

My dad owned it from 2 years old but recently upgraded to an XF. Now it's mine! I have fallen for it but have to go with my head rather than my heart. Always garaged, well maintained, but really rusty, all four wings gone. That's Devon salty air for you.

phirouyer · Postby **phirouyer** » Wed Aug 01, 2018 4:08 pm

I noticed a leak on the thermostat housing cover of my X308. (This is the old plastic type). I have ordered the new all-aluminium tower, which I should receive to-morrow. Though it does not seem to require high skills, I can't change it at home and my local shop may not be able to to it before next week.
I must urgently leave next monday, and do 300 miles (including 150 miles on motorway). My question is : can I do it with the leaking cover ?
Since I noticed the leak, because of the smell a couple of days ago, I have added a little coolant, but I had nol lost enough to get a "low level message" . I believe that there is a minor crack at the bottom of the recession for the Allen key. From your experience, do you think it would stand a 5 hours drive ?
I am afraid the pressure would expand the crack. Thank you for your advice.

Andy P · Postby **Andy P** » Wed Aug 01, 2018 5:06 pm

Hi phirouyer,
If you mean the cap on top of the tower change the old cap for the aluminium one you have from the new tower,
I wouldn't risk it otherwise but it's your call at the end of the day.
Hope that helps mate.
Enjoy the luxury.
Andy

phirouyer · Postby **phirouyer** » Thu Aug 02, 2018 11:29 am

End of story : the plastic housing was still in good shape, the problem was with the cover (or possibly the cover seal. I ordered an aluminium unit yesterday at 2 pm. I received it this morning at 9.30 ! I was able to fit the new cover with the new seal : the thread is identical. No leak ! But I shall have the aluminium fitted as soon as possible. It looks much more durable.
It is a shame that Jaguar tried to save a few pounds with this plastic housing.

BrianG · Postby **BrianG** » Thu Aug 02, 2018 1:12 pm

Glad you have the leak fixed. When I had a '99 4 litre X308 I found other places leaks can occur unexpectedly: 1) at the thermostat tower base gasket to the block, 2) unless you intend to fit a new top hose soon make sure that the top hose spring clip is backed up by an additional jubilee clip. The spring clip does not grip tightly enough on an older hose and can allow it to blow off the stub and then you REALLY will have a coolant leak! (ask me how I know!)