Thanks for this Bob - I am now confident enough to refurbish my injectors, hoses and paint the fuel rail (I have even bought the paint you recommended). I just need my car back from the shop where I am getting an aluminium radiator and twin electric fans fitted - to help with my own car’s hot running...
I have had a similar issue with a pre-HE Vanden Plas, it turned out to be the thermostats, someone had fitted incorrect ones that did not have the feet to block off the internal bypass once the engine warmed up. I replaced the thermostats and the temperature dropped to normal and stayed stable. I later found that a major parts reseller had the incorrect listing in the catalogue used by the counter staff.
This is a common story with these cars. The correct thermostats are hard to find. Gates brand works for sure. Many other thermostats listed as correct are in fact not correct.
I’m having the exact same problem and am following all your attempts right along with you! Checking fuel pressures and injection operation was on my to do list but now i will check those things sooner rather than later. Thanks!!
I use two ear clamps on the fuel lines of our 5.3 cars, including the injectors and fuel rail. The purists will hate it, but they are neat, super easy to remove when you need to and they never leak. Years ago I made a custom tool to be able to install them on the injectors whilst still on the car, nowadays though you can even get a pair of crimping pliers that lets you do that too. Hope you get to the bottom of the hot running issue soon - always a scary proposition with these engines.
Just a quick question, have you verified your temps with a thermocouple? The XJS water temp sending unit fails in such a way that they begin to over-report temps. This usually gets worse fairly quickly though eventually reporting correct temps as close to overheating.
My radiator caps aren’t sealing. That can’t be helping my overheating issue. Have you checked yours, @TCCC? They’re both fairly new, but it wouldn’t be the first time I ordered parts for the XJ-S that turned out to be wrong. 😠
@@thecampchaoschronicles9567 That might be good general guidance but in my particular case I think it is pretty likely that my filler necks are a bit messed up and/or one or both of my caps are incorrect. But for the sake of diligence and completeness, what might cause excessive pressure in my cooling system?
Hi, Mohammed here from the UK. I'm considering doing a harness change, would you know the connector part number / type I need please. Great vids keep up the good fight. 👍🏻
The rear 4 cly. On the V12 retain the most Heat thats whyI think the stock radiator Can’t handle it especially in heavy Traffic an aluminum radiator with Twin Electric fans flowing 3500 cfm Is the answer
I just swapped out Waxstat thermostats for Gates. The Gates ones are noticeably longer, both open and closed. In my case it didn’t matter - my car still over heats - but it’s good to know the Waxstat ones are unlikely to close that bypass port.
head gaskets....a combustion leak test on the coolant system would make a quick diagnosis but beyond that... mls gasket replacement (if there is such a thing) or....a laser cut copper sheet head gasket (fab required :-) the horror in situ for the head removal/replacement.
@@thecampchaoschronicles9567 question. remember the 2.9l that used the single v12 head? i am looking for a pair of those intakes. there is a plot afoot. ;-)......
So that's what you look like without a hat! I was wondering 😁 Out of curiosity why didn't you just rest the AC compressor on the radiator? Wouldn't it have been easier than using the engine cradle?
Good news, bad news. Cars running smoother, but still no joy with the cooling issues. Great increase in fuel economy. Is that a HE engine? At this point I'd back flush the radiator, flush the engine and heater core, and new coolant. Good luck.
Bob, you are a machine.. lol.. keep up the great videos.. I've worked on so many of these British cars throughout my career,, you sometimes run to a corner and start crying while sucking your thumb.. lol.. I've learned long time ago, right bank always runs warmer, I always grab my very accurate temp gun, or if you're rich buy a thermo image camera... I would start reading temps at plug bases, than as close as possible across the water jackets.. than remove the heat shields and verify exhaust temps across each cylinder.... you would be surprised how much of a difference and a diagnostic aid it would result from. From misfires, lean conditions, flow problems, etc.. i teach my students to this day on new vehicles.. You already know this, but help others,, I don't know if it cost alot out there, but you can have a shop with emission equipment quickly test exhaust, printout for less than $100 here in Canada.. You should show everyone a quick test with your volt meter reading on the O2,, .1v lean,, .9v very rich, but unfortunately you have to have it gear... Or jump the 2 wires near ECU, into adjust mode... Good luck and may the tool gods be with you.. lol
Nice video great tip on using the engine bar to raise compressor! Keep doing what your doing. Thanks again
Thanks for this Bob - I am now confident enough to refurbish my injectors, hoses and paint the fuel rail (I have even bought the paint you recommended). I just need my car back from the shop where I am getting an aluminium radiator and twin electric fans fitted - to help with my own car’s hot running...
Great program
I have had a similar issue with a pre-HE Vanden Plas, it turned out to be the thermostats, someone had fitted incorrect ones that did not have the feet to block off the internal bypass once the engine warmed up. I replaced the thermostats and the temperature dropped to normal and stayed stable. I later found that a major parts reseller had the incorrect listing in the catalogue used by the counter staff.
This is a common story with these cars. The correct thermostats are hard to find. Gates brand works for sure. Many other thermostats listed as correct are in fact not correct.
I’m having the exact same problem and am following all your attempts right along with you! Checking fuel pressures and injection operation was on my to do list but now i will check those things sooner rather than later. Thanks!!
Hey did you ever figure it out? I'm in the same situation lol
I use two ear clamps on the fuel lines of our 5.3 cars, including the injectors and fuel rail. The purists will hate it, but they are neat, super easy to remove when you need to and they never leak. Years ago I made a custom tool to be able to install them on the injectors whilst still on the car, nowadays though you can even get a pair of crimping pliers that lets you do that too.
Hope you get to the bottom of the hot running issue soon - always a scary proposition with these engines.
Thanks for the info.
Just a quick question, have you verified your temps with a thermocouple? The XJS water temp sending unit fails in such a way that they begin to over-report temps. This usually gets worse fairly quickly though eventually reporting correct temps as close to overheating.
Another interesting and informative video, enjoying these troubleshooting episodes as well as the various other topics you cover. 👍
My radiator caps aren’t sealing. That can’t be helping my overheating issue. Have you checked yours, @TCCC?
They’re both fairly new, but it wouldn’t be the first time I ordered parts for the XJ-S that turned out to be wrong. 😠
Both of them not sealing would be odd. More likely too much pressure in the system.
@@thecampchaoschronicles9567 That might be good general guidance but in my particular case I think it is pretty likely that my filler necks are a bit messed up and/or one or both of my caps are incorrect. But for the sake of diligence and completeness, what might cause excessive pressure in my cooling system?
Caps replaced. No difference.
If your back East could you have salt damage on the brass fins that dissapate heat from the radiator tubes
I am looking at buying a 94 xjs with a 4.0 six in it It is the one with a silver top. Any recomendations of what to look out for.
I'm afraid I don't do much work with 6 cylinders. Sorry.
Just watched one of your videos where you used IronTite on the XJS, a possible contributor to your overheating issue?
No chance. The particles are minute, stay in suspension and keep moving.
Hi, Mohammed here from the UK. I'm considering doing a harness change, would you know the connector part number / type I need please. Great vids keep up the good fight. 👍🏻
Hi Mo. This is the part you need. Available from a number of sources. www.summitracing.com/parts/rnb-85850?seid=srese1
These are the boots. www.ebay.com/itm/224074630043
Many thanks 👍🏻
The rear 4 cly. On the V12 retain the most
Heat thats whyI think the stock radiator
Can’t handle it especially in heavy
Traffic an aluminum radiator with
Twin Electric fans flowing 3500 cfm
Is the answer
I Had this odd issues once, it ended up being the incorrect thermostats, they weren't closing the front bypass port all the way.
The cooling system flush is next and checking the thermostats will be part of that video.
I just swapped out Waxstat thermostats for Gates. The Gates ones are noticeably longer, both open and closed.
In my case it didn’t matter - my car still over heats - but it’s good to know the Waxstat ones are unlikely to close that bypass port.
@@lebojay Flushing and thermostat inspection will be the subject of the next video.
head gaskets....a combustion leak test on the coolant system would make a quick diagnosis but beyond that...
mls gasket replacement (if there is such a thing) or....a laser cut copper sheet head gasket (fab required :-)
the horror in situ for the head removal/replacement.
The gaskets aren't leaking. It's the material betwqeen the fire rings and perimeter seal that turns to junk.
@@thecampchaoschronicles9567 question.
remember the 2.9l that used the single v12 head? i am looking for a pair of those intakes. there is a plot afoot. ;-)......
.... thought you might be of help finding a pair as spare parts for jags appears to have a spot in your heart/collection.
=dok=
Will the Jack Plate be available again???
Possibly this winter when things slow down a bit.
That’d be great news. I’m willing to send an online payment for an extra used one.
Uhhhhh...let's see how this one works out.
So that's what you look like without a hat! I was wondering 😁 Out of curiosity why didn't you just rest the AC compressor on the radiator? Wouldn't it have been easier than using the engine cradle?
It's always a bad hair day here at Camp Chaos. The hoses for the A/C compressor are pretty stiff and the engine support IS really easy.
@@thecampchaoschronicles9567 😀Yes I'll be replacing all of mine on Moby as soon as I replace my broken recycler! God forbid I loose any of my R12!
Do you anyone that does the same as your program (which is excellent) but works on the XJS as a 6 cylinder
Thanks. No, I'm afraid I don't know of any others.
Good news, bad news. Cars running smoother, but still no joy with the cooling issues. Great increase in fuel economy. Is that a HE engine? At this point I'd back flush the radiator, flush the engine and heater core, and new coolant. Good luck.
That's the next stop. It would have been the first check to make it the cooling system hadn't been replaced/reconditioned two years ago.
@@thecampchaoschronicles9567 Has there been any coolant loss?
@@jeffharrison5265 None.
It is an HE.
@@thecampchaoschronicles9567 Any chance the thermostat could be faulty?
Bob, you are a machine.. lol.. keep up the great videos.. I've worked on so many of these British cars throughout my career,, you sometimes run to a corner and start crying while sucking your thumb.. lol..
I've learned long time ago, right bank always runs warmer, I always grab my very accurate temp gun, or if you're rich buy a thermo image camera... I would start reading temps at plug bases, than as close as possible across the water jackets.. than remove the heat shields and verify exhaust temps across each cylinder.... you would be surprised how much of a difference and a diagnostic aid it would result from. From misfires, lean conditions, flow problems, etc.. i teach my students to this day on new vehicles..
You already know this, but help others,, I don't know if it cost alot out there, but you can have a shop with emission equipment quickly test exhaust, printout for less than $100 here in Canada..
You should show everyone a quick test with your volt meter reading on the O2,,
.1v lean,, .9v very rich, but unfortunately you have to have it gear... Or jump the 2 wires near ECU, into adjust mode...
Good luck and may the tool gods be with you.. lol