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This is a Real Puzzler-we need to think about this for a minute.
GM has had this very same problem for at least 2 decades- across the board on many engines. And many engine revisions. For instance the 1997 truck 350 had it, the 2002 engine had it, the 2007 engine had it. And it was a real common problem. Note 2 things- these were all heavy duty engines and a stainless part would actually be less money. Its a simple t-fitting.
Posting a video of a guys t-fitting breaking in the part store parking lot. BTW I replaced mine with a metal one I fabricated almost out of the factory.
The crossover pipe that is under supercharger and the corresponding piece on top and in front of the throttle body used to be made from aluminium. Check out the pre-facelift
XF supercharged cars. On those, the only plastic part was the heater core coolant crossover pipe in the back. You could use one of those as a template!!! Keep us posted on the progress. This is definitely something that I would be interested in. I just replaced the entire system (water pump, hoses, thermostat, and the %(^*^#@ plastic crossover pipes !!) It's not something I would want to do on a regular basis. I asked the dealership about replacing the plastic pipes with the old aluminium pipes, but htey do not make them anymore and the plastic pipes are a replacement.
Where is the truth? The only original parts, or for that matter factory parts on my 77 Harley are the engine cases, the heavily modified heads and the frame, also modified. Did Harley design all the those discarded parts, some of which left on their own accord, to fail at certain and deliberate intervals. I wouldn't believe that even if the empirical evidence suggested it. Were many of those parts designed and manufactured in a complex matrix of cost, duration, usage expectations, ride-ability, laws and regulations? Absolutely. Were some defects learned after production began? All the time, and many small companies look to the warranty period as a time to retrofit.
And of course the big question, did I improve on almost if not every replaced part and system. Always. Was I smarter than HD engineers, or have better R&D, or more sophisticated tools? Nope. But I had the hindsight they did not. They had to design and build a running model which I could then troubleshoot for weakness.
And, as is common in most complex machines, it takes time and distance. It was five years before the de Havilland Comet came apart over the Mediterranean, and it's unlikely the result of designed obsolescence by an engineer or bean counter.
And then there are common manufacturing practices, which spreads costs across multiple manufacturers and not just models. Think of our sticky buttons. A good idea which disintegrated in practice and affected a host of luxury brands. Does anyone believe it was intentional as a way to top off a dealer's coffers?
I have a son who works for Tesla. There is probably not a single component that hasn't been rethought on the Model D, and yet **** still breaks. The latest victim being frame fatigue, not unlike what the glorious de Havilland Comet experienced. Too much torque too often at zero momentum for existing automotive engineering formulas.
My 86 635CSI came from the factory with a radiator that needed replacement at 90K, at plastic impeller water pump needing replacement at 120K, and a long block good for 300K as long as the oil was changed regularly and the valves made right every 20K.
One might ask, what should be the expected lifespan of a complex machine, many time stressed to its engineered limits. I don't have that answer. But I do have a ton of one off vastly improved Harley parts.
A better example would be the 1999 to 2007 GM trucks and truck-based SUVs (I bought a new Sierra in 2005) which had a noisy steering column. GM's first solution was a lubrication kit (I bought one) which required you to remove the intermediate steering shaft from the truck, take it apart, inject some grease into it and put it all back together in the truck. Not a hard job, maybe 45 minutes but you had to do it about every 3-5,000 miles or it'd start making noise again. Then an aftermarket part manufacturer came up with a vastly improved design and other aftermarket manufacturers followed suit. Eventually, GM came up with a new design themselves and issued a new TSB calling for replacement of the intermediate shaft with the new design, but not until a couple of years after superior parts were already available in the aftermarket.
Regarding British cars in warm climates (someone mentioned it early in the thread), this is something I can completely agree with. I have to be careful when and where I take my Lotus Esprit (2001 twin turbo V8) during the warmer months because I get real skittish when I see the coolant temperature start creeping above 100C and hover around 110C and sometimes move near 120C (the top end of the gauge). I've replaced one of the cooling fans and if I still have the car next year, will probably look at flushing the radiator and adding more cooling fans. Just as a shark has to keep moving to breathe, so too the Esprit needs to be moving for enough air to cool it.
I loved that car, but was it ever a nightmare. You will particularly love the XKR. Because it will truly impress you how far the industry has come. Think reliability of a Lexus, comforts of a Rolls, soul of a Jaguar. You wont get the Formula one soul of an Esprit, well you can if you ingest some spirits. You know what price that F1 soul comes at. Still take it any day over a countach.
Busy week at home and at work! Let me see if I can catch up here...
PA66 is compatible with antifreeze, but it is not compatible with the corrosion inhibitors present in OAT coolants. From what little reading I've had a chance to do since my last post, Zerex G05 and the OEM Jaguar coolant are HOAT and won't deteriorate the plastic. I still want to read the links you guys have posted... things just got really busy for me, so it might be a while. Thank you guys for posting them, though; I've learned a few things since starting this thread.
As for why not just replace the part every seven years? Well, why? For some, OEM is great. For others, OEM is a great starting point. I've never tried to convince anyone that what I'll be making is right for them. The whole purpose of this was to see if anyone else wanted one while I was making mine. It's a free market; buy whatever you want.
My ratings... well, I got my A&P cert back in the mid 90s and never really did anything with it. I was an ASE Master Tech but let that expire ten years ago. I'm a CFII in rotorcraft and am single piston engine rated in fixed wing. My work with the C130s is on the electrical and avionics end of things, and believe it or not, they didn't require me to get an avionics rating. Seriously. When I was in the military, I worked with explosives, but that has no bearing on any of this. I am not a machinist and while I've farted around with lathes and endmills, I've never taken a class or been paid for it. That's why I'm subcontracting this out to guys that do it for a living... they're better than me, and have the time to do it that I don't. What's the one saying out there... something about surrounding yourself with people smarter than yourself?
OK, what else? I'm posting from my phone and the mobile site doesn't let me scroll up to reference posts. Oh yeah, something something Rolls Royce... I *love* those engines and how much more advanced they are than the Allison T56 they replaced. But, the FADECs and the CANBUS networks associated with them can be a pain sometimes. Thankfully, I don't work on the flight test side of the house.
I'll post back when I get the first pieces.
Sorry to dig up an older thread, I'm trying to find out if DEXCOOL in fact does eat away at the plastic parts in our jags,
i'm running Prestone DEXCOOL, and willing to swap it out with something better (G05 it looks like you are suggesting?)
I've read through numerous threads and articles, but you seem to be the most knowledgeable.
If you guys want to really get into the nitty-gritty of it, Dupont has tons of tests on PA66 (nylon 6,6 the plastics used in our cooling parts)
and dex-cool vs other coolants,
Check the plastic code on your cooling system parts. Jaguar chose to use just about any style plastic and they are not fully compatible with any one coolant... Bean counters won over the engineers.
I also have a leaking plastic coolant piece... the heater manifold (part #AJ814007 on a 2010 XK NA). Fortunately it's seeping and not gushing. I noticed my coolant was low when changing my oil this weekend. It was easy to spot the general area of the leak... onto the transmission below the firewall and along the top ridge of the heater manifold. I got a loaner pressure tester from Pep Boys, cleaned off the heater manifold and put up to 20 psi on the cooling system (the cap is rated 140 Kpa = 20 psi). The pressure slowly decreased and I found a bit of seepage on the heater manifold near the throttle body heater hose connection but not a lot (the last picture below). I didn't see any leak on the throttle body heater hose itself or where it connects, so I'll replace the heater manifold and see if that cures it. I'm just trying to decide if I should replace the other coolant hoses and plastic bits around the front at the same time, even though they all look fine. I have 62K miles on my 2010 XK.
We have to be completely honest with ourselves.
Has Kathy Bates lost her looks or have we lost our libido?
Truth is that for all of us there was a time that absolutely anything would do.
So here is the engineering question: if its lasted flawlessly for 8 years in the most extreme conditions; without unknown side-effects, such as added weight, decapitation in impact, heat-soak- why would you not go with a tried and tested commodity?
From the perspective of a manufacturer whose products go around the globe, I want to see them outlive me- thats the way we sell more. The engineers want to see them last forever (its not their nickle) the folks who want to see it last the shortest is the consumer- who is unwilling to pay for more upfront and even less in maintenance.
Not that long ago, it was customary to replace all the rubber hoses at the 8 year mark.
Are there any good products one can spray or otherwise apply onto these stressed plastic parts to maybe help prolong their survival under the hood?
Are there any good products one can spray or otherwise apply onto these stressed plastic parts to maybe help prolong their survival under the hood?
Its not the elements that cause the failure. Its the coolant running through them that the plastic was no well tested for.
So no nothing can be done externally unfortunately. But one should not worry about it either.
Just be vigilant on the coolant levels and get a temp monitor, you may never have a problem.
Mandrake, did you ever get around to making better coolant fittings over the cheap plastic ones? Sorry for resurrecting an old thread.
I was drenched in antifreeze today as I found my problem with codes P0171 and P0174. The plastic intake pipe was cracked resulting in an air leak.
Just barely touching the plastic fitting on top of the throttle body housing resulted in breakage due to it being extremely brittle.
I ordered a new coolant return hose assy. with all plastic fittings from my local Jag dealer and new intake pipe from Harper Jaguar. Harper has a very nice online ordering website and are very aggressive on the best price possible. Dealer wanted $253.00 for the intake pipe and their price was $135.00 for the same oem part.
Unfortunately, you can't just buy the plastic fitting itself. What a cheap design... Looks like over the winter I will be removing the supercharger and replacing the coolant hose under the sc along with any other brittle hoses/fittings.
I only have 41k on the car but the heat and years did a number on the coolant hoses/fittings. Stainless fittings would be nice upgrade over these cheap plastic ones!
No worries! Hope it helps, if not try the 'related topics' box at the bottom... I'm new here and finding the search returns LOADS of results to sift through, but once I find one thread about what I'm after the rest seems to come from that 'related topics' box.
Mine were replaced in warranty and crumbled to dust after just 3 years. So I tried the aluminum versions. Lasted about 3 months and they began leaking intermittently at the fittings. They’re as tight and flush as possible but I reckon the o-rings included might be at fault.
For the second time in three months, I've gotten a coolant shower after barely touching the plastic pieces in the cooling system when hot. By barely touch, I mean literally put my finger on the under side to see if there's any weeping at a fitting. This garbage is more fragile than a millennial's feelings, and I am D-U-N done screwing around with it. I spent about two hours cleaning up the garage and the engine bay and boy howdy, am I pissed off.
The short and curly of this is that over the winter, I'm going to begin to build some stainless pipes and fittings to replace this PA6 GF30-50 crap that the cheap bastages at Jag went with. The first piece will be the plastic overflow/burp pipe and its tees and fittings, followed by that plastic manifold in the back of the engine as well as the rubber pipe that runs under the blower. These three items are the three that I see fail the most. I already have a metal supply house, a machinist and a welder all lined up, and my question to you guys is this: should I make jigs to replicate these parts for anyone else? Additionally, can anyone think of any other plastic pieces that commonly fail?
The cost is going to be what the cost is going to be. To me, the piece of mind knowing that plastic has been replaced with stainless steel in a cooling system on an engine as expensive as these is priceless. I haven't crunched the numbers yet because at this point, it's all going to be one off stuff. If you're as frustrated as I am and refuse to replace old with new that's just going to fail again, keep an eye on this thread.
I'm here to tell u that you got millennials and Gen Z mixed up when it comes to feelings cause millennials grew up in the 90s and we all know how the 90s roll.
09-17-2017, 11:25 PM
