Good day fellow Jag mavens. I have not posted or commented of late here mostly due to time constraints. I have been exceedingly busy. The other factor is that I find what I need by searching the archives and don't need to ask many questions or make many suggestions. That said, I think it's good "best practices" for me to give back a little of what I've been given regarding a repair I recently made.

Many here are well aware of the failure rate of the coolant recovery tanks on our X350's (pretty much 100%, mostly within 80K miles of service) and mine has been no exception. At around 75K miles, my 2005 XJR been leaking at the notorious nipple, the one that exits the tank for the return hose outlet. I found a link where our old friend "MK82" had repaired his tank by removing the offending nipple, drilling out the tank's entry hole and replacing the nipple with new plastic tubing, glued in with adhesive and reattached to the outlet hose.

So, I did that. It took a whole lot of JB Weld to seal the joint between the new tubing and the tank, but I finally got that sealed up.

However, somehow in the same general area, leaking continued. Finally after around a week of head-scratching, I found a pinhole leak on the top of the tank right near the nipple area, where coolant was slowly seeping out when the motor was running. SO, here's what I did: I slathered JB Weld all over that area as well. Picture attached to illustrate.

Today, NO LEAK! I understand this is probably stopgap, that this tank will eventually fail in a more dramatic fashion as I've read others doing. But for now, I'm good to go at a total cost of around $10.00, for JB Weld, plastic tubing/connectors and coolant.

Here's my question, folks. The "Coolant Level Low" warning continues to come up. It clears in the morning first thing, then comes back after the car reaches operating temperature. Do you believe I'll need to clear that code with a code reader, or is also possible that I may have now have a faulty sensor, or the magnet has been displace? Keep in mind that I had no warnings or issues before my leak occured.

 

Are you sure there is no air in the cooling system? Did you check the coolant level with the engine cold by removing the radiator cap? I would be concerned about the expansion tank repair, since the glue may not adhere well to the expansion tank after temperature cycling over time and I would expect the leak to come back.

 

Why not just buy a new tank? The price of doing business.

 

Ryejag, Yes. I've made sure that there is no air. I've cycled the heater several times, per Jag's instructions, letting the car cool down, and then unscsrewing the expansion tank relief valve. And yes, the car has the correct level of coolant. BTW, the car has never so much as hinted of a change in operating temperatures from normal during this entire saga.

It has been almost 2 weeks since I made the repairs, and there are no signs that the adhesive is not adhering well. IMO, JB Weld will not exhibit such characteristics. It forms a highly reliable seal to plastics. I will be keeping an eye on it. If it does give out, I will try to note it on this thread.

Jag XJ8 Red, Why not just buy a new tank? To save money. I am on a VERY tight budget. I have 4 kids between the ages of 3 and 12, and was laid off as of 7/31/12. Times are tight.

My original question remains, but I believe I'm correct in concluding that the "Coolant Level Low" code and warning will have to be cleared through the computer, as it remains to this day.

 

I'd suggest replacing the tank to prevent overheating and destroying the engine. Jaguar of Greenville (877-906-2117) has taken over the discount parts sales from Nalley. Just bought my tank last week for $125. Don't know what shipping would be. Don't know if you have to clear the coolant low level with a code reader, but you do if you get the check engine light for temperature mismatch (air bubble at sender). Venting is the pain. Can't seem to get all the air out even with brutal's suggestions of squeezing the top radiator hose while the vent is open. Will keep trying though. If anyone has any other suggestions for the venting, I'd appreciate it.

Dale

 

It's not just the tank that leaks, all the plastic 'Y' pieces/elbows etc are prone to failing. Just fitted a generic aluminium expansion tank and made all new connectors from T6 aluminium. Hopefully the car will be cured of future leaks now. If there's much interest I may start making more pipe connectors to pass on. My x350 had a faulty connector between the header tank and thermostat (joins several large and small water pipes). Cost at Jaguar Ł85, cost to make...... Just Ł60!

 

That's great thinking, JagX350. I'd love to see photos of your installed aluminum tank, as well as the metal connectors. I wonder if I could adapt this solution to my XJR, as the tanks are different than the normally aspirated XJ's.

 

Trav, i would have recommended permatex 2 part plastic epoxy for plastic repairs. I have a jb weld mixing palate to mix jb weld. Its plastic and after it dries i just flex it alittle to seperate the hard epoxy off the plastic, it doesnt stick
not to **** on any parades........I agree otherwise in many cases. save where you can, spend where you need or want to

 

+1

 

Good to know about the Permatex epoxy. I am aware of plastic-specific epoxies and thought of going out and buying some for the job, but I had the JB Weld hanging, so I just slathered it on. So far, so good. Brutal, I am now going to look at the repair areas more often since you came in and commented on JB Weld and plastic. But to this point, there have been probably over a hundred heat cycles by now, and the JB Weld is holding a seal and staying adhered.

 

Well, Brutal, you called this one. I was under the hood on Friday and lo and behold, coolant was visible ( mere drops mind you) collecting on the seam area of the recovery tank below the patched area. It is such a small leak now, that it would take months to lower the coolant level noticeably, but surely it will increase over time. Looks like I'll be buying some Permatex plastic epoxy pretty quickly. Thanks.

 

When you get the low coolant warning is the tank still full ?
There's a Biblical thread on this - due to the float losing buoyancy.

 

I'd like to see a post of your aluminum tank also. I live in Texas and my 05 x350 tank when out last spring. It only lasted about 40k miles. So having an non plastic option would be nice.

Even better would be to have a aluminum upper thermostat housing. Mine went out about the same time as the coolant tank. I'd love to see an after market part (like the one for the older models). These plastic parts are a joke and nothing more than a money maker for the parts distributors.

 

You do not have to clear a OBDII code to make the coolant warning light go out. It comes on and off as the coolant level rises and falls in the coolant tank. It simply has a floating trip sensor in the tank.

At times when mine had a leak, the low coolant low light would come on and go off while driving and stopping at traffic lights.

When the system cools, the excess coolant is automatically drawn from the reservoir back into the radiator. This type of cooling system is known as a closed design because coolant that escapes past the pressure cap is saved and reused.

 

The discussion on fixing the tank is kind of funny. This is serious penny wise and pound foolish activity. The few bucks you save will go away when you are in Tucson on a trip and the thing dumps your coolant. The ones with the generic tanks that develop a coolant leak on a trip and the low coolant light never comes on may lose their engines over this dumb move. Sorry, had to say it!

 

I had the same issue in my 06 Super V8. The Low Coolant light would come on intermitently, eventhough the coolant level was correct. After some head scratching, I checked the sensor that plugs into the bottom of the tank and found that it was loose. Apparently, it is the plug in and twist type. It had worked its was loose and caused the issue. You've probably checked this but its worth a shot if you haven't. Good luck

 

Fundamentally I agree with you. My situation is a bit unique in a couple of ways. Number one, I'm cash-strapped and have lots of little mouths to feed, and number two, it is seldom my car sees freeway use, especially of any long distances (over 20 miles one way). If I were to plan a trip in the XJR, I would change the recovery tank straight away before leaving town. So for the moment, I'm content to tool around town as-is.

 

Whether its a patched tank or the original tank... the OEM plastic tanks are going to fail. The fact is we are riding around on an accident waiting to happen on both the plastic upper thermostat housing as well as the coolant tank as per the original OEM design. Time will tell on the JB weld option but it is conceivable that a patch job may even hold better than the original plastic.

So while I agree it is an area of concern I would not automatically discount the value of an epoxy patch. I have used products such as Marine-Tex on metal and plastic repairs that are indeed stronger than the original design (Compressive Strength 13,000 PSI, Tensile Strength 4,000 PSI).

If you have never used a product like Marine-Tex you should check it out. I use it all the time on lots of things (cars, boats, pools… you name it)... also note its primary application is for fixing boats. There are tons of people that have used it for in water repairs, cracked engine heads and blocks, etc and tons can testify its value. These products are not gimmicks’ and they have stood the test of time in real life and challenging situations.

As for the generic tanks... are you referring to the aluminum tank that was mentioned in this thread? Are you suggesting the plastic is superior to aluminum or is there another concern? I would assume the replacement aluminum tank would have the sensor and all the fittings that are on the original but it was not clear... that's what we asked for a picture or more details. Do you know something about the tank that was mentioned?

Thanks for your feedback...

 

Interesting info on Marine Tex. I see they make a poly grade specific for plastics. I am sure I will have a use for it someday!

RyeJag

 

Ya... They have lots of great products... but the one I have the most experience with is the "might repair kit" (original 2 part epoxy kit). Once cool thing about it you can apply it, and then heat it with an infrared heat lamp. I do this for a few minutes and then let it set for a half and hour or so and it is hard as a rock.

You can also add coloring agents to change the color when you mix it. Once cured, Marine-Tex can be machined, drilled and tapped as well as filed, sanded and painted.