When i drive a few miles My xj8 appears to boil and then leak out appearing on the ground just beneath the radiator at the end of it on the passenger side, I don't know where it is originating from , right now it is more water than antifreeze because I have to top it up, is it safe to drive a a bit as long as I keep it topped up? There are products claiming to seal leaks ..are they to be avoided? I have no idea if it is leaking when I drive along.... Is a leak simply aleak or a symptom of something else? Many thanks

 

How long have you had this problem and how long have you had the car? Has any work been done recently?

The reason I ask is it sounds like the small lines from the pressure tank may be connected wrong. They should cross each other.

 

This.
If your lines are correct have a pressure test performed.

Also avoid "stop leak" products as they will gum up/corrode the whole system in the end.

 

I forgot to mention that the thermostat can fail in the closed position, resulting in overheating which could destroy the engine. Likewise, the water pump vanes may have crumbled and it's overheating. This is all guesswork, as we don't have all the details.

 

I have had it a few months and it has started happening recently , would you have an image of the pipes you mean so I could check , thanks again

 

hi I have attached a couple of photos of my pipes are these correct or wrong??? Thanks

 

They are wrong.

I bought an XJ8 a little over a year ago and noticed I had to add coolant every week or so, not a lot but still...it was losing some. The reservoir connections were put on backwards by the previous owner and I didn't know the difference. The folks on this forum informed me of the correct arrangement of those lines and after I switched them I never lost any more coolant. I have no idea where it was leaking though, I just got a "low coolant" message every week or so and topped it off.

 

How do yo swap them around?I am not a mechanic but I would be willing to do it if is simple. Thanks

 

Hi Trevor,

Those connectors are notoriously annoying to disconnect. Once you figure out how they work it's not too bad, but many people have broken/snapped the fittings or hoses trying to figure out how to disconnect them. Re-connecting them is easy, just push them until they snap.

There is a small plastic tool that many have said came mounted somewhere in their engine compartment; either on the throttle body or on one of the connections itself. Check the part load breather fitting on the valve/cam cover. That's a similar style connector coming out of the front section of the LHS valve/cam cover.

I could never find this elusive plastic tool on any of my cars. I use two small flat head screwdrivers to spread the fitting such that it can be twisted off. With a little patience and practices you'll figure it out and it'll be easier in the future. Just be careful. Don't break them.

 

If you do, you'll have the pleasure of finding out
how special Jaguar thinks their plastic parts are.

 

Hi thanks for the great advice I have swapped the pipes around and so far no sign of leaking ..using the little plastic tool thingy which was attached to soime other pipe thing... Can I continue to drive the car OK for a few days until I get the correct mix of water/coolant back in at the minute it is more water than coolant because I had to top it up a bit a few times the weather is mild so no worries about freezing but I don't want to damage anything??? Thanks again for the advice

 

My only concern would be that a predominantly water concentration will have less resistance to boiling. Monitor your coolant temperature very closely and you will probably be fine.

If you did not use distilled water when you were topping it off then there could also be various cotaminants that have been introduced to your system. Again, in the short term probably not that big a deal.

Drive it enough to confirm that the switched hoses were in fact causing the leak and then flush and re-fill. That's what I would do...

 

Hi thanks for your help I have a thread on here about an intermittent start problem,would yoiu be able to shed any light on the reason why my car sometimes takes 2 or 3 turns of the key??? It cranks fine , new battery in place recently but doesn't fire, I have gone into a bit more detail on the thread, can't figure it out and mechanic got no error codes starts fine then other times just can't fire, on the plus side it hasn't failed entirely !! But I would like to sort it, it seems to happen in waves a bit but I'm stumped so any advice would be great

 

Did you eliminate the fuel pump and/or filter as the problem? If there are no codes and a starting issue then I would investigate fuel pressure first.

I know many consider fuel system cleaners to be "snake oil", and maybe they are right; but, I have seen improvements using them before. Most notably the Redline brand fuel system cleaner. If you have a clogging injector or something then, in theory, running a cleaner through it could help. Cheap and easy to try.

Speaking of injectors, if you have a leaking injector that is just starting to leak (intermittently), then that could be causing raw fuel to accumulate in the cylinder occasionally resulting in hard starting.

I always replace the fuel filter on any used car I buy, just to establish a starting point. It's SO often overlooked by previous owners that the likelihood is very high it's the original filter that came on the car. Just my experience. Plus, it's relatively easy to replace.

As a more obscure possibility, the coolant temperature sensor has given me starting issues on a few cars over the years. That's generally only an issue with cold engine starts though, but again...it's a cheap part and easy to replace. I usually replace the CTS on any used car also, just to be sure.

As usual I'm all over the place, but those are my first thoughts.

 

Where exactly is the connector tool located @, my associate just acquired a new to her XJ8 & of course the lines are crossed.

 

Crossed lines are correct!

 

I meant to type backwards there lol. Her low coolant light flared today as well.

 

Factory placement for the 'pipe tool' is at the front end of the Part Load
Breather hose wich is fitted to the l/h driver side US cam cover.
Look at the forward end of the cover and you should see it as a small 'U'
shaped device.
When using this you press it downwards so it 'spreads' the two little
tangs attached to the pipe connector and then pull directly upwards to remove the pipe ;o))

 

Kudos sir !

 

Anyone got a photo of this tool !
Be nice ...lol