Ticking Time Bomb
 

Went to a Lambo event this weekend, and met the owner of a VR Racing establishment. He was telling me how they just lost their 2011 Range Rover Sport that recently purchased used. He said the first sign of trouble was a low coolant warning. They just added coolant and kept driving it with plans to take care of any small leak later on. Few days later his wife was driving it, and the engine was blown in what seemed an instant. Clearly, whatever plastic pipe was leaking finally let go in a big way and the engine overheated immediately and then warped the heads and coolant was sucked into the cylinders. These engines just can't take any overheating and as soon as you lose pressure in the cooling system from a blown pipe, the heads will warp. This is unlike the days of the old Chevy 350 iron block and heads that could take it, so most people don't believe it's possible.

He was quoted $18-20K to fix what was a blue book $21K car with a used engine that would not be fully warrantied.

He sold it for $5K in scrap and walked away.

Ask yourself how you would feel if you lost $15K tomorrow because a plastic pipe blew out. It's hard to stomach, and you think it won't happen to you, but if you have these 5.0L engines with their original plastic, it's a ticking time bomb if you don't replace it. There's going to be a lot more of these stories in the years ahead, and it will happen most to the people that aren't on these forums to know about the problem to fix it before it happens, and they won't be on here to tell their story when it does happen. The $1500 in parts and the DIY or paid labor to replace all the plastic is just the price to pay to own these cars now. If you can't pay it, you better sell it before you lose most of your money in the car.

This is probably due more to the fact that the Low Coolant and Engine Overheating warnings come on much too late coupled with drivers thinking they can make it to the next exit or gas station. It's so important to have some sort of OBD app or something with an alarm to warn you when the temp is BEGINNING to rise.

When those fused together plastic pipe halves let go, there's no app that's going to save you. If you lose pressure in the cooling system, the boiling temp drops right away and the car overheats almost immediately. The heads on these cars just can't take it like other engines. I had a car that my daughter drove for 3 days with no coolant. It would sputter on her, and gave her warnings and she ignore them. Fixed the cooling leak, and it was fine for 3 more years before we sold it. The 5.0L just can't do that.

Change your plastic and give up on silly apps!

Just curious...
I assume that the bulk of the plastic in the cooling system is the same on the V6 3.0 as the 5.0 V8....Especially the big crossover at the rear of the heads. I work with a seriously talented 3D printing guy and have been thinking about 3D printing a scanned crossover pipe in wax and then high pressure investment casting the part in bronze or aluminum, he can do either.In the process the part could be cleaned up design wise a bit, but it might have to be cast in two parts and have a union in the middle....I was thinking about redrawing the cross section in the middle round instead of rectilinear and adding circumferential barbs so a simple hi temp hose and clamp set up could be used the join the two halves of the part. The hose would also dampen vibration some, which would be a good thing.My buddy is a serious car guy, he gets it.

It seems to me if this part, and select other weak sisters in the cooling system could be rendered in metal they would become much more reliable , thereby getting a nasty monkey off our backs for both the six and eight cylinder motors.For those of use who want to enjoy our lovely XF's over the long haul this could really be a blessing.

Thoughts and advise are welcome, I am crazy about my XF and would like to enjoy care free motoring for years to come...

Paul

I don't think it's fair to label the apps as silly - there are lots of pieces of useful information available on the CANBUS that Jaguar chooses to not make available to you - coolant and oil temperature are just two I can think of in this situation. Why not both? Change your plastic and the apps can give you a useful idea about what's going on with engine temps and everything else.

I think Paul's right, the only true fix for this in my opinion is to have a rear crossover pipe made that's better than the original - I mention this pipe specifically because it's really the only one you can't easily monitor the condition of with the engine/supercharger/chargecooler in situ. When I rebuilt and refitted my engine I fitted a new OEM crossover pipe but this obviously still has the plastic-welded seam so still has the potential to fail in the future. I wonder how expensive it would be to have the crossover pipe laser-scanned and then 3d printed as one piece plastic that's strong enough? Or alternatively have one fabbed up in aluminum? I don't think a simple hit temp hose setup would work as there's also a rear temperature sensor mounted in the crossover pipe.

What percentage of these engines are being driven by a woman? What percentage of these women are going to fire up an app and watch it non-stop while driving just incase the plastic that you didn't bother to change goes boom?

And even if you are going to watch an app while driving, your engine will be toast before you can pull over.

So its a silly idea to monitor plastic that should have been changed with an app. It won't save you. Still don't believe me, ask the dude that was monitoring his car with an app why he's pulling off his heads now.

There are apps and OBD readers that will alert you to whatever temp you choose, without even having to open the app and monitor it at all. For example, the one I have is actually a small LCD screen tucked away under the dash that is always connected to the OBD port. It comes on automatically with the car and reads the engine temp digitally, amongst other things.

Plus there have been numerous overheating stories recounted where the engine was not destroyed because the driver pulled over right away.

I'm not saying that replacing aging plastic pipes is not important...of course it is. What I'm saying is that there are additional ways to prevent catastrophic damage when an overheating event does occur.

Oh NO! Not.... (dun dun dun) a WOMAN?!!?! Driving a car? Whatever next?

News just in, the 1950s want their gender stereotypes back

Stereotype, or freaking reality?

Reality.

You are smoking dope if you think the solution is for all Jaguar and Land Rover owners with these cars to set up supplementary instrumentation with an OBDII connector set up to wirelessly transmit either through Wi-Fi or Bluetooth to a smartphone running an app that was downloaded and specifically configured for extra sensitive alerts on certain parameters.

LOL, doesn't that sound stupid if you read that out loud? Maybe you can go to the dealer and run that idea by the women looking at cars in the showroom.

Seriously, were you born this supercilious or do you have to work at it? You're twisting what people are saying, and very specifically ignoring salient points of multiple people's posts solely to create an opportunity to talk down to everyone else.

Nobody on this thread has suggested using an app as a solution, and multiple people have acknowledged that the plastic pipes on these cars deteriorate and could do with being swapped out - but you're ignoring all that because then you get to infer how stupid everyone but you is for even considering the idea of using an OBD2 app.

Wind your neck in and give it a f**king rest.

Speaking of plastic cross-over pipes, the big one across the front of the engine is also a weak link and has been known to split at the seam.
On the 2009-2011 XFR this was an alloy pipe and never caused any problems, but then in their infinite wisdom JLR changed it to a plastic pipe on the 2012 XFR, and all AJ126 (V6SC) have the same plastic pipe.
To make matters worse the plastic pipe is not backwards compatible with the older alloy pipe.

Is it our fault that Jaguar (and most all other manufacturers) decided to ditch actual temp gauges long ago? Go yell at them instead of us.

Even if all the plastic was brand new under my hood, I would still keep the OBD reader hooked up.

There's the front crossover, the rear crossover, the thermostat housing, and those thin hard plastic hoses that go to the reservoir and the reservoir that will all ruin your day. Even if those thin hoses break (and my crumbled in my hands while I was removing them), the system will lose pressure and the coolant will turn to steam in the heads and warp the heads.

It all needs to be replaced. It's not cheap, it's not easy, but it's either change them or play a version of Russian Roulette with your XF.

The cooling system is the biggest weakness of these vehicles. If any coolant message pops up, its best to not drive the vehicle at all, until the issue is dealt with. Last year mine had water pump replacement and pipes replaced.

So what's your point? The engine will be damaged before you can do anything from that ODB reader. Just ask this guy: https://www.jaguarforums.com/forum/x...cement-214153/

"Luckily I have been running the Torque app ever since I tuned the car, so it helped when the pre-set alarm went off telling me my coolant temps were too high. I purposely set the PID to warm me if coolant temps go above 205 deg.F so I think I had plenty of warming before the engine overheated too bad. I never got any engine temp warning from the dash, I pulled over and opened the hood and saw coolant running out from behind the water-pump. I had another water-pump leak (second time this has happened!). Towed the car home.

I replaced the water-pump...this time I shelled out the cash for a dealership sourced water-pump (looks the same as the cheaper versions, but figured it may last longer)

But, I am now losing coolant over the course of my daily drive. I would say I probably lose about a 16 oz of coolant over a 100 mile trip."

You think you're better than him? You think you can shut it off faster than him? Maybe you can shut it off faster than him, but your engine will still be damaged. But hey, you'll still have your precious app to look at even though your car is in the junk yard.

Here is a question more on point...

From all the pipes in this world, that have been used for cooling... there is absolutely no metal pipe out there that can be used to replace this plastic thing?

Even a hose... can't we modify a hose to make it fit!?
"Like" for example... have the end connectors made out of metal and then a hose going from one end to another!?

If anyone has a broken part, send it over - I can 3D model one and then we can send it out for 3D printing.
But, I would honestly still find a different solution where a hose can be used rather than plastic again... hoses are more flexible and they can last longer than a plastic pipe.

I have an alloy pipe on my engine - in fairness, that joiner piece with two O-Rings on it is a bit of a PITA, but you're right in that at least it doesn't split like plastic pipes. I assume that while the alloy and plastic crossover pipes are not compatible, you can presumably change them as a group: the plastic crossover pipe & Y pipe it connects to, or the alloy pipe, joiner, and Y pipe.

The problem is that the rear crossover pipe isn't just a hose bridging the two heads together, it's a pipe bridging the two heads with an additional hole for the rear coolant sensor, as well as T-piece for the hose that connects to the throttle body. There's pics of them all over the internet, the part number is AJ812458:

https://cimg1.ibsrv.net/gimg/www.jag...f568a43dc6.jpg


It would be entirely possible to have one made out of aluminum or similar, and I'm sure you could also 3D print one as a single piece much better than the plastic seam-welded original. However, despite the rather alarmist title and tone of this thread, I don't think there's enough call for someone to do a decent run of them worth selling. I'm sure the vast majority of these crossover pipes haven't failed. Over time they become brittle and more prone to it, sure, but how many owners do you think are willing to go through the veritable ass ache of changing it? It's not exactly a 1-spanner rated Haynes job.

Yep, the only coolant line/system problem or leak I ever had on the XFR or F-Type was one of those thin plastic expansion tank tubes across the top/front of the engine.
The day I got my crank pulley fitted on the F-Type the mechanic pulled me over and showed me signs of dried coolant and said he had traced it to a very slow leak right at the far end (away from the expansion tank) of one of those thin tubes. He explained that they are crap quality plastic which goes brittle with age and heat cycles and eventually they crack, and I needed to get mine replaced before a small leak turned into a gusher. The part itself was not in stock but he cobbled up a replacement tube from some silicone rubber coolant hose. As he was cutting the old tube off he showed me how brittle it was, it was just like uncooked spaghetti and crumbled into little pieces! This on a car with only around 25,000 miles on it! Then about two weeks later I got the dreaded "low coolant" warning so I immediately pulled over and checked the temperature gauge which was reading normal, ie smack on half way. I popped the hood and checked the expansion tank and it was way low, about 1/4 full. There were also obvious signs of a coolant leak right at the end of that replacement piece of tubing, ie in the same spot the original tube had cracked. As a precaution I had put a 5 litre bottle of pre-mixed coolant in the hatch two weeks earlier so I topped up the tank and drove home carefully, keeping an eagle eye on the temp gauge. The "low coolant" warning came up again just as I pulled into my garage.
Long story short this time the leak was caused by the mechanic using the wrong type of clamp and then over-tightening it, which caused the clamp to cut into the end of the replacement rubber tube and make a small split. It was also apparent that I hadn't lost much if any coolant pressure, there was still plenty of coolant in the system even after the warning was triggered, and the leak had stopped once the coolant level dropped to about 1/4 of the expansion tank. My guess is that once it got to that level there was not enough pressure to force any more up to the top of the tank and into and along the main expansion tank tube. I bought a couple of new clamps, pulled the hose off of the leaking end, cut the last cm of it off where the split was, put the hose and a new clamp back on, and it's been good as gold ever since (over a year now).
I bought a new expansion tank hose in any case (you can only buy the whole thing right from the expansion tank but it was fairly cheap, around $40 AU IIRC) but I am yet to fit it as I couldn't figure out how to release two of the connectors. Next time I need to see a mechanic I will get it fitted.
Moral of the story - even on a "young" Jag you should keep an eye on these damn plastic coolant tubes, and not just the big ones but the little skinny ones as well!

Funnily enough, me too. The connector in the middle of the alloy crossover pipe that goes to the expansion tank. They get brittle and the pieces of plastic that lock the tube in suck. Which is to say nothing of the little plastic tube that goes into the water pump :icon_screwy: