Hi all -

This is my first time asking a question of the group. I have a 2004 XJ8 that has had a few problems with coolant leaking. First the dealer replaced the thermostat gasket. They however neglected to notice the coolant overflow nipple had cracked as they seem to do. Due to this the coolant overflow hose came off and caused an overheating incident which may be relevant. A new coolant tank was installed, then the coolant overflow tube had a small leak, which was then replaced as well.

Now I am getting a coolant smell, only when I stop and start the car, never when driving. It is a very slow leak as I haven't had to add coolant since the other leaks were repaired (a month or more) and the level in the coolant tank has barely changed. I decided to look into it myself and it seems the leak is coming from the ends of the coolant distribution block (not sure what the formal name for this part is, maybe the whole thing is the thermostat housing). I put a photo and circled the problem areas below:


It apparently drips directly onto the drive belt, which I'm sure is contributing to a cold squeal I am also experiencing. It is worse on the right of the photo (drivers side). Has anyone ever experienced this; and is there a simple fix? I have an extended warranty so I can get it taken care of for just my deductible but I'd like to see what the forum thinks as well.

Thank you. Love the insightful posts here.

 

Is this not the same part that cracks in various places due to its being made of plastic ? And isn't there an aluminium replacement made by Welsh Enterprises Inc of Ohio costing $66 ?

 

Not for the 4.2 and yes you need a new thermostat housing. Easy to do and dont replace the neck that goes under the intake. You have to pull the intake and you will have to replace the intake steel shim gaskets(they always leak vacuum when loosened) just take off the oring from the new neck and put on the old neck. The laeking part is the plug on the end of the housing. You can be real cheap and epoxy cover it after you clean real well if youre into shade tree repairs

 

Thank you all for the information! I shall relay the info to my shop next time I take her in if I don't epoxy it first

 

jagman... aka


don't do it man...

 

Thanks Jagman619 for the detailed description and the great photo. I started smelling coolant, just as you had, from my '04 XJ8 and your post led me right to the problem.
Also, thanks to BRUTAL for spelling out what is needed as well as the time and labor saving tip on the neck o- ring replacement.

 

Looks like Welsh Enterprises Inc need to get busy on an aluminium manifold for the 4.2 then !!

Interestingly this same thing is plastic on my Rover 75 V6, and that also cracks. Trouble is it is buried under the inlet manifolds. I have an aluminium replacement produced by a chap in South Africa sitting in my garage waiting for it to fail, except it seems strangely durable on my engine !!

PS If you're wondering why I post on a Jaguar site when I have a Rover, I am looking at getting a Jaguar again, I had them in the past.

 

I consider Land Rover and Jaguar cousins... distant, and only related by marriage.

 

@SleekCat - I am happy to help. Since these cars and those that can care for them are relatively scarce, helping each other will keep them on the road, where they belong!

@Fraser - The plastic parts meet the manufacturer testing in the lab, which is why they use them. I think in some real world situations, they don't hold up as well. For example, my car was purchased in Phoenix, AZ and was likely subjected to city traffic in temperatures approaching 120F or almost 49C. I personally have seen the display read 117F or 47.2C during a trip taken to Las Vegas last year. That plus dry, dry air is hell on plastic parts.

Good luck with your Rover. I had for a time a 1990 Rover 800 with the Honda/Acura 2.7L drivetrain (sold in the states under the Sterling brand). I purchased it for only $1100 USD, and with a little simple troubleshooting it went close to 50K miles in comfort and economy before the transmission failed. There are probably still a dozen or so puttering around San Diego that I've seen.

That said, the Top Gear episode that featured parts falling off and other matter of malaise with a similar sedan was in some ways very accurate

 

Here is a question regarding the availability of an aluminum replacement. Can anyone here look at this and make an educated guess (based on placement of outlets, bolt-holes, etc.) as to whether this might possibly fit the car? I have spoken with a representative at FCP Groton who assured me that it would fit a 2004 Jag XJ8 4.2L. Here is a link to the Ebay listing: (just in case the link is not live, it can be looked up on Ebay as Item# 280243785761:

http://cgi.ebay.com/ebaymotors/Jagua...Q5fAccessories