Suspicious Thermostat failure
#1
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2000 XJ8 59K miles.
Had Radiator flush at Jaguar this week. (Last radiator flush was 6 years ago.) Drove 42 miles & had breakdown! Red light, Low coolant message, smoke from under hood! Pulled over immediately. Coolant all over the engine compartment & under car. Called Jaguar & they arranged Tow. Now I’m told it was the thermostat. Housing failed causing the hose to come off & dump fluid. Unrelated to my radiator flush service. Bill will be $700+
I don’t believe in coincidence. I personally replaced the original thermostat 7.5 years ago when the car was 4 years old with a genuine Jaguar thermostat I bought from Jaguar. I suspect the mechanic made some error during the radiator flush that has caused this. The temp gauge did NOT move up. Was right in the middle when the red light came on
Any thoughts?
Thanks,
Steve
Had Radiator flush at Jaguar this week. (Last radiator flush was 6 years ago.) Drove 42 miles & had breakdown! Red light, Low coolant message, smoke from under hood! Pulled over immediately. Coolant all over the engine compartment & under car. Called Jaguar & they arranged Tow. Now I’m told it was the thermostat. Housing failed causing the hose to come off & dump fluid. Unrelated to my radiator flush service. Bill will be $700+
I don’t believe in coincidence. I personally replaced the original thermostat 7.5 years ago when the car was 4 years old with a genuine Jaguar thermostat I bought from Jaguar. I suspect the mechanic made some error during the radiator flush that has caused this. The temp gauge did NOT move up. Was right in the middle when the red light came on
Any thoughts?
Thanks,
Steve
#2
#3
#4
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From Invoice: “Sticking Thermostat. Brass Insert in Thermostat housing loose. Replaced Thermostat & Thermostat Housing. ” Service advisor says the housing was brittle.
I’m still wondering if the pressure of the power flush caused this. Maybe it would have happened in the next year anyway but perhaps it was the age & brittleness that could not take the power flush? Or the thermostat stuck closed & the build up of pressure would have busted open any housing? How many times must the thermostat in XJ’s be replaced? I knew at 4 years regardless of mileage they often failed. When mine did in 2004 literally 1 month after warranty expired, the symptoms were the radiator fan began to run a few minutes after shutting the car off.
So my 1st one lasted 4 yrs + 1 month, 2nd one lasted 7 years & 5 months.
I’m still wondering if the pressure of the power flush caused this. Maybe it would have happened in the next year anyway but perhaps it was the age & brittleness that could not take the power flush? Or the thermostat stuck closed & the build up of pressure would have busted open any housing? How many times must the thermostat in XJ’s be replaced? I knew at 4 years regardless of mileage they often failed. When mine did in 2004 literally 1 month after warranty expired, the symptoms were the radiator fan began to run a few minutes after shutting the car off.
So my 1st one lasted 4 yrs + 1 month, 2nd one lasted 7 years & 5 months.
#5
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Question - is the housing bakelite or aluminium? I suspect by the comment 'housing bushing loose' that it is bakelite. They are part of the Ford ownership crap. And yes, they do fail, usually by warpoing and leaking, and because it is down in the valley, it often isn't noticed until the damage is done. Having said that, the dealership should know this, and after all, it is that knowledge which you pay them for. Here in Australia (Brisbane) we can get full aluminium housings (top & bottom) - my Business partner stocks them. If you want I'll ask him for a price after Xmas (I'm not sure which days he will be working), and we can airmail them to you. Mail won't be expensive, because they are not heavy, and you could pay on my PayPal account which would also save time and give you protection, since you don't know me from a bar of soap.
Aus Post website about $30 Aus for up to 2kg Airmail.
At a guess, someone overtightened the housing bolts.
cheers
Languid
Aus Post website about $30 Aus for up to 2kg Airmail.
At a guess, someone overtightened the housing bolts.
cheers
Languid
#6
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$700 is a bit excessive. The housing is $90-120, the thermostat shouldn't be much, the r&r can be done in approximately an hour but probably bills out at 2 hours, and coolant doesn't cost much. Bill out should be $300-400 from a shop. $700 is way too much.
I've seen the odd things with the thermostat housing, but nothing connected to a flush. However, it is a Jaguar and they do very odd things sometimes. I've seen the retaining tabs break off and make their way to the water pump and the ruin the pump. I've seen them crack/leak after fixing another coolant leak. Etc.
When you replace the house be sure to get the aluminum. As for life of the housing. I had my plastic one make it 110k miles before r&r, and that was in 4 years. I've never had an aluminum one go bad. I would base the life of the coolant housing on miles and quality of coolant rather than over time.
I've seen the odd things with the thermostat housing, but nothing connected to a flush. However, it is a Jaguar and they do very odd things sometimes. I've seen the retaining tabs break off and make their way to the water pump and the ruin the pump. I've seen them crack/leak after fixing another coolant leak. Etc.
When you replace the house be sure to get the aluminum. As for life of the housing. I had my plastic one make it 110k miles before r&r, and that was in 4 years. I've never had an aluminum one go bad. I would base the life of the coolant housing on miles and quality of coolant rather than over time.
#7
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i guarantee you have a rotted plastic housing. Dealers and shop I know of do not do a power flush, but drain and refill with flush, run and flush and fill again with 50/50 mix. Its a coincidence. Those hoses(lower radiator where it connects to the t stat housing) blow off alot and thats one reason I replace the hose barb(t stat cover) with the t stat housing too because the retaining ribs go away and an old hose is soft and tends to not hold welll like when new. They just work themselves off right there. I would replace the crossover pipe too since its plastic and when hot you can break them apart with your hand when theyre rotted. Thats why the hoses start looking swollen, they get soft and expand and contract.
$58COOLANT, $115 HOUSING, PLUS BARB AND 2.5-3HRS LABOR AT $125 PLUS SHOP FEES AND TAX. DO THE MATH
$58COOLANT, $115 HOUSING, PLUS BARB AND 2.5-3HRS LABOR AT $125 PLUS SHOP FEES AND TAX. DO THE MATH
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#8
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Thanks for the replies/info; Languid, Digiorno & Brutal!
I have only 59,000 miles on my 2000 XJ8. I’m the original owner.
To be clear, my Thermostat & thermostat housing have already been replaced by Jaguar yesterday. I assume my factory original housing from 2000 was the bakelite/plastic. I will email Jaguar to ask if the replacement was, in fact, aluminum.
Overall the respondents who appear more knowledgeable are saying it was a coincidence. My best guess at this point is I had a brittle, original plastic T-stat housing which was going to leak or crack soon anyway. Since I personally replaced the T-stat in 2004 following instructions from one of the forums & am not a mechanic & have no torque wrench, I may have overtightened it. Not sure if I was warned to not overtighten, I think I was. I cannot find my step by step instructions that I used in 2004. But, the fact that it lasted 7.5 years suggests I did not overtighten. If my Thermostat failed in the closed position, the pressure could not only pop off a lower hose but burst the brittle, weakened housing. Now WHY did the t-stat fail again? Do these Jaguar T-stats need regular replacements as maintenance?
Has Jaguar modified this part since 2000? I know when I had the fans running after shut down & searched forums I learned many need to replace the t-stat at 4 yrs. regardless of mileage. I had to do this in 2004. I had thought once & done with new t-stats. Now 7.5 yrs, later it failed even worse that the 1st time. Hope it was a fluke & I will have gradual warning if in 4-8 years I again need a new t-stat. Slight overheating or intermittent problems with fans running after shut down once again. Prefer to not have hoses pop off <GRIN>
My old top small hose (3-4” long?) did appear ballooned out to me.
Exactly like the one in this photo:
Jaguar thermostat housing 4.0 xk8
I noticed that after yesterday’s repair they have a new small hose there & new, worm style hose clamps & I was told the old Jaguar original hose clamps should never be reused & don’t hold as well.
Is the “crossover pipe” just past the small hose? Moving from the T-stat to the front bumper, 1st you have the small top hose & then 90 degree bend in both directions is the “crossover pipe?” (See pix in the link I gave)
If so, it looks like original equipment & feels very firm, not at all rotted. My other hoses look good & feel firm too. Jaguar said I did not need new ones. Twice. Once when I asked with the flush & 2nd time when I asked after the breakdown & replacement of the T-stat & housing.
BTW, on a different forum I was told to flush system, replace t-stat every 3 years. Seems like overkill to me, especially if you do not DIY.
Merry Christmas & Happy Holidays!
Steve
I have only 59,000 miles on my 2000 XJ8. I’m the original owner.
To be clear, my Thermostat & thermostat housing have already been replaced by Jaguar yesterday. I assume my factory original housing from 2000 was the bakelite/plastic. I will email Jaguar to ask if the replacement was, in fact, aluminum.
Overall the respondents who appear more knowledgeable are saying it was a coincidence. My best guess at this point is I had a brittle, original plastic T-stat housing which was going to leak or crack soon anyway. Since I personally replaced the T-stat in 2004 following instructions from one of the forums & am not a mechanic & have no torque wrench, I may have overtightened it. Not sure if I was warned to not overtighten, I think I was. I cannot find my step by step instructions that I used in 2004. But, the fact that it lasted 7.5 years suggests I did not overtighten. If my Thermostat failed in the closed position, the pressure could not only pop off a lower hose but burst the brittle, weakened housing. Now WHY did the t-stat fail again? Do these Jaguar T-stats need regular replacements as maintenance?
Has Jaguar modified this part since 2000? I know when I had the fans running after shut down & searched forums I learned many need to replace the t-stat at 4 yrs. regardless of mileage. I had to do this in 2004. I had thought once & done with new t-stats. Now 7.5 yrs, later it failed even worse that the 1st time. Hope it was a fluke & I will have gradual warning if in 4-8 years I again need a new t-stat. Slight overheating or intermittent problems with fans running after shut down once again. Prefer to not have hoses pop off <GRIN>
My old top small hose (3-4” long?) did appear ballooned out to me.
Exactly like the one in this photo:
Jaguar thermostat housing 4.0 xk8
I noticed that after yesterday’s repair they have a new small hose there & new, worm style hose clamps & I was told the old Jaguar original hose clamps should never be reused & don’t hold as well.
Is the “crossover pipe” just past the small hose? Moving from the T-stat to the front bumper, 1st you have the small top hose & then 90 degree bend in both directions is the “crossover pipe?” (See pix in the link I gave)
If so, it looks like original equipment & feels very firm, not at all rotted. My other hoses look good & feel firm too. Jaguar said I did not need new ones. Twice. Once when I asked with the flush & 2nd time when I asked after the breakdown & replacement of the T-stat & housing.
BTW, on a different forum I was told to flush system, replace t-stat every 3 years. Seems like overkill to me, especially if you do not DIY.
Merry Christmas & Happy Holidays!
Steve
#9
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I heard back from my Jaguar Service Adviser re my questions.
I have a replacement Plastic t-stat housing. Jaguar has improved this with thicker plastic. Aluminum t-stat housing is NOT a Jaguar part, rather it is an aftermarket part that does not line up correctly & causes problems. T-stat cover was replaced along with t-stat. Yes, air/water reverse cycle flush was done.
He said no need to change t-stat every 3 years.
I have a replacement Plastic t-stat housing. Jaguar has improved this with thicker plastic. Aluminum t-stat housing is NOT a Jaguar part, rather it is an aftermarket part that does not line up correctly & causes problems. T-stat cover was replaced along with t-stat. Yes, air/water reverse cycle flush was done.
He said no need to change t-stat every 3 years.
#10
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Yes the crossover pipe (crosses) from 1 cylinder head to the other and the stub hose off the t stat connectos to it.
If it were mine i would have replaced the heater hoses under the intake aat the same time as the t stat housing if theyre original. And replaced the lower hose that blew off along with a why not upper hose. Other than that your okay. T stat every few yrs, no but if never had 1 stick or surge on me again after popping the brass check ball of the t stat.
If it were mine i would have replaced the heater hoses under the intake aat the same time as the t stat housing if theyre original. And replaced the lower hose that blew off along with a why not upper hose. Other than that your okay. T stat every few yrs, no but if never had 1 stick or surge on me again after popping the brass check ball of the t stat.
#11
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However, if I owned a shop or where a mechanic on track hours, then I would probably agree with $700.
#12
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Iconoclast ,
Of course the Jaguar Service Advisor was going to tell you that: he has a vested interest. The truth, however, is actually a little different. Bakelite was urbanized in the early ‘20’s after being developed around the turn of the century. It is the original ‘thermo-set’ plastic, developed and used for its electrical insulating properties, and used predominantly for electrical appliances including light fittings, radios, home appliances etc. It is by nature a ‘brittle’ form of plastic, which even in that environment becomes more brittle over time. Down in the valley of a V engine, which is a very hostile environment, simply exacerbates it weaknesses. Increasing the thickness doesn’t resolve the problem: it may increase the lifetime between failures.
The aluminium substitute is indeed an aftermarket product. It is my understanding that it is made by a German Engineering company that makes other components under licence for Jaguar. My business partner assures me that it is suitable for use on S & X Jags where it fits perfectly and causes no problems. He has been supplying & fitting them for some time because of the warping & disintegration problems which occur with the Bakelite units. I am also led to understand that there is a minor difference in the (outlet?) pipe angle when used on X-Type Jags, which is not a major problem.
He also raised his eyebrows when I told him of the ‘2.5 to 3 hours’ to fit. He observed that 1.5 hours is more than enough time to do the job, as Digiorno calculates. Greed is not good, it drives good customers to look elsewhere for service. (and I read that on a sign in an LA petrol (gas) station in 1978).
The retail price of the complete kit here is Aus$230 which includes seals etc, excluding only the thermostat itself. Once installed, unless one is silly enough not to use ethylene glycol based coolant, it will last as long as the engine block itself. If Forum members want the kit, my partner will supply them at a 10% discount + the airmail postage of $24, or Sea mail @ $17..
It seems to me that ‘Service’ has changed from “looking after the customer” to “looking after the dealer’s bottom line”.
If anyone wants a kit, email me at euroselectvehicles@hotmail.com PayPal payment accepted.
Cheers guys,
Languid
Of course the Jaguar Service Advisor was going to tell you that: he has a vested interest. The truth, however, is actually a little different. Bakelite was urbanized in the early ‘20’s after being developed around the turn of the century. It is the original ‘thermo-set’ plastic, developed and used for its electrical insulating properties, and used predominantly for electrical appliances including light fittings, radios, home appliances etc. It is by nature a ‘brittle’ form of plastic, which even in that environment becomes more brittle over time. Down in the valley of a V engine, which is a very hostile environment, simply exacerbates it weaknesses. Increasing the thickness doesn’t resolve the problem: it may increase the lifetime between failures.
The aluminium substitute is indeed an aftermarket product. It is my understanding that it is made by a German Engineering company that makes other components under licence for Jaguar. My business partner assures me that it is suitable for use on S & X Jags where it fits perfectly and causes no problems. He has been supplying & fitting them for some time because of the warping & disintegration problems which occur with the Bakelite units. I am also led to understand that there is a minor difference in the (outlet?) pipe angle when used on X-Type Jags, which is not a major problem.
He also raised his eyebrows when I told him of the ‘2.5 to 3 hours’ to fit. He observed that 1.5 hours is more than enough time to do the job, as Digiorno calculates. Greed is not good, it drives good customers to look elsewhere for service. (and I read that on a sign in an LA petrol (gas) station in 1978).
The retail price of the complete kit here is Aus$230 which includes seals etc, excluding only the thermostat itself. Once installed, unless one is silly enough not to use ethylene glycol based coolant, it will last as long as the engine block itself. If Forum members want the kit, my partner will supply them at a 10% discount + the airmail postage of $24, or Sea mail @ $17..
It seems to me that ‘Service’ has changed from “looking after the customer” to “looking after the dealer’s bottom line”.
If anyone wants a kit, email me at euroselectvehicles@hotmail.com PayPal payment accepted.
Cheers guys,
Languid
#13
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I believe the thermostat housing is made of fiberglass reinforced plastic, not bakelite, which is not used in auto applications anymore.
The use of aftermarket parts in a dealer environment is usually avoided due to fit and warranty issues.Most customers take their cars to a dealer because they want manufacturers parts installed on their vehicles for piece of mind. This is not to say that aftermarket parts won't work correctly, but they usually are not tested as rigorously as manufacturers parts, and they usually will not pay for labor when they fail.Customers get sick of that pretty quick. The new plastic housings should be fine.
The prices charged seem excessive to me though.
The use of aftermarket parts in a dealer environment is usually avoided due to fit and warranty issues.Most customers take their cars to a dealer because they want manufacturers parts installed on their vehicles for piece of mind. This is not to say that aftermarket parts won't work correctly, but they usually are not tested as rigorously as manufacturers parts, and they usually will not pay for labor when they fail.Customers get sick of that pretty quick. The new plastic housings should be fine.
The prices charged seem excessive to me though.
#14
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