BIG PROBLEMS with the XJR!

We wanted to provide an update on the XJR as we know some content on it has slowed recently. Some problems have reared their head since the major cooling service.
We have a plan on how to rectify everything, but it has delayed our initial plans with the car. Thank you everyone for following along with our trials and tribulations of Jaguar ownership!
Be sure to follow us for more videos on this car as well as others in the Low-Tech fleet!
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[@stephensomersify]

Makes me smile to hear that you "LOVE the car" - My respect to hear your in depth knowledge = subscribed - old git, UK

[@LowTechGarage]

Thank you! Just finishing up the head gasket series. You should check it out!

[@interceptor124]

You have an interesting projekt here. However, if the XJR/X308 is in good original condition, it has a bulletproof engine: Deborah (my XJR) loves the open motorway and she is doing 160 mph with a smile on her face. Greetings from Germany!

[@LowTechGarage]

Thank you!

[@kennethtalbott2233]

brilliant

[@interceptor124]

@@kennethtalbott2233 make sure the previous owner was a true Jaaag lover with a stable bank account bevor buying any XJR/X308.

[@kennethtalbott2233]

@@interceptor124 too late for that, bought my Daimler super V8 a couple of years ago. nice but room for improvement, just removing the tank for fuel pump replacement. made a tool today to get the fuel lines out from under the tank. my xjs was loved by the previous owner, she had it for twenty six years and spent a fortune on the old girl although some of the bodywork left a lot to be desired but i sorted all of that last year. she's close to being back on the road. got a SWB V12 series one a series 3 double six and the holy grail S1 vanden plas.

[@interceptor124]

@@kennethtalbott2233 very nice collection of Jaaags Keep up the good work👍

[@Roscoeverdin5469]

Sounds like you have a good plan. New bolts, proper head gaskets and have the heads resurfaced. Is a valve job in the works as well? I and I am sure your followers are looking forward to your results. As a bonus to us viewers, we get to see the top end tear-down and rebuild along with the further enhancements you had planned. I hope you find a proper work area.

[@LowTechGarage]

We are going to have the valves all inspected and see if a valve job is required while they are off. We recently got our hands on a draggy so we should be able to share the performance gains as well. Thanks for your support!

[@jameswhite9025]

Weird check but pretty easy on the cap, take it off, try to blow through it from the bottom, if you can its shot and allowing the coolant to purge into the catch tank, mine was, tossed it, put on a new one, problem solved. Do an exhaust gas check on the coolant to see if it is lifting the heads before tearing into it.

[@jameswhite9025]

I have the stage 2 kit on my XJR-100, bigger lower pulley smaller upper pulley, had to get the head bolts out and install an ARP stud kit to lock the heads down.

[@LowTechGarage]

Where did you get the ARP stud kit. Would really like to get this on our XJR but cannot source one so far.

[@mikejacobs4727]

This video made me a little nervous . I have a black s type r I just did major service on. I didn't do the pully " yet". The car is back together and the other day I was really driving it hard and when I stopped I had some pressure comming out of the tank. I found the cap wasn't tight and it hasn't happened again thank God. These cars are beautiful but the problem no one can fix my car so I bought a professional scan tool and did the trans , engine everything myself. I have many hours into the car as I blacked out the whole car lights grill , marker lights and wheels. I installed a BORLA exhaust with carbon fiber tips , x pipe and mina gallery intake. I also deleted the cats and just with these small upgrades my car is extremely responsive and really gets up and goes. One thing I'd suggest is replacing the hose that connects the intake elbow to the supercharger . The extra pressure might rupture the stock hose. I used a high pressure hydrolic hose for mine. We did injectors , all the sensors . Glad your making this video as there arent alot of video on these cars . Good luck

[@LowTechGarage]

Thanks for the input, it sounds like you have a really nice S type R! We should be posting an update on the progress soon.

[@nicethatness]

Glad to hear the optimism man keep it going I got the upper pulley and a whole bunch of other parts sitting just waiting to be installed looking forward to seeing yours 😎😎 one question though what is the bypass valve because I’m stumped 😂🤦🏼‍♂️

[@LowTechGarage]

Thanks a lot! All part of the adventure! The bypass valve is tucked at the back of the supercharger on the driver side (at least on my car) and is used to modulate the boost when you snap the throttle shut among other things. If you check out our video on the supercharger removal I point it out in there and it is easy to see with everything removed :)

[@LowTechGarage]

It is connected to the two small hoses at the back of the charge air coolers. I believe it can be seen in our supercharger removal video

[@alekjuskevice]

I’m repairing the supercharger on my 2000 XJR. I’ve found your posts very helpful. I thought you said you were posting a list of parts numbers hoses etc that you purchased? Is that available in one of your posts, and, If so, which one please?

[@LowTechGarage]

The parts are listed in the description of this video. kzbin.info/www/bejne/fWewcqupeZ19iZo

[@santiagohernandez422]

I just orderd all the gaskets for the car and head gaskets for my car. Hopefully the overheating will change after that. I usually drive it and it overheats if i am stuck in traffic or in idle.

[@LowTechGarage]

Good luck and let us know how it works out!

[@brandonherrera2891]

I would 100% get rid of the cats, especially if you do lower pulley as well. Sorry this happened though. On the bright side, the car will be better. I've read on forums that if you have the smallest upper and biggest lower, arp studs are a must. Just keep that in mind, or maybe ask xjr-99 or Avos.

[@LowTechGarage]

Thanks a lot for the tips! I was having a hard time locating a vendor selling the head studs. The new parts are starting to roll in so hopefully can start the project soon!

[@mikejacobs4727]

I deleted my cats on my str . I read a watched a lot of video that basically said the car will lose low end tourque . I personally feel a huge difference in the performance of my car. The car sounds amazing and you can hear it breathing easy. Although not legal , in my state we have no DMV inspections . My car is used for shows and is driven sparingly. Great advice

[@alekjuskevice]

I would not pull the heads off. First re torque them, which may have been the problem, the heads weren’t re torqued, they need to be with stretch bolts. Try it, you might save a lot of time and trouble, and, you have nothing to loose. If you really want to be a stickler, replace the head bolts with new ones, but do one at a time.

[@LowTechGarage]

Thanks for the tip! The car is going into be serviced here soon. I’ll be sure to check.

[@powersliding]

its pretty know as the most reliable jaguar ever though so im sure everything else is ok...it would be so cool if you sort out the power hike issues and have one cool and classy car with muscles to boot

[@LowTechGarage]

I am eagerly awaiting a few parts for the 1959 chevy so I can drive that over the winter and get it properly sorted

[@StanCarrico]

def would recommend having heads machined if you are going to do this much work.. do it once kind of thing!

[@LowTechGarage]

Thanks for the advice. They will be going to the machine shop to be fully gone through

[@lp76100]

Surface the block as well as the head

[@hotmasked1]

Replace the radiator also ! just because your in there already

[@LowTechGarage]

Thanks for the tip!

[@superpeluso1]

In fact this cars are so awesome that people always approach me to see what kind of car it is might not be a Ferrari but it’s an awesome car to have ! … I had several actual real offers but my kitty cat has no price tag 🏷…. No way I could replace at all

[@LowTechGarage]

We feel the same. Adore the car.

[@callumduncan6728]

before you do anything to the cylinder heads get an exhaust gas analisis kit to put where your rad cap goes it will be proof positve that it is the heads, canceling out any other posibilitys . also pressure test the coolant system a crack in the intercooler rads could give similair symptoms , iam far from convinced its the head gaskets

[@LowTechGarage]

Thank you for this tip. We did an exhaust gas test in the cooling system which was inconclusive. Any idea how to confirm damage to the heat exchangers?

[@gregdettling6693]

@ LTG and German Interceptor from Lovely Bavaria. Big update on my 1998 Black and Chrome XJR X308 project/repair/complete engine replacement. The replacement engine with 140,000 original kms just arrived. It was the only one available in Canada! A few completely rebuilt/ reconditioned ones were found in California for between around 14,000 to 16,000 USD We went with this one because in Canada and well within budget and the inspection and amount of kms looked good. They can work with it I think. Ironically the motor came from very close to the same place my car was originally purchased in April of 1998. I understand that it was taken out of an XJR that was totaled off in a crash. We will inspect and use the supercharger that is the very best out of the two. If both are good, we will use the original as it still looks very good cosmetically. I’m curious if this car can compare to a German car? I’ve owned a red 2003 BMW 320i and I was very happy with it. This is my first Jaguar.

[@LowTechGarage]

Our personal experience is these focus more on the luxury touches such as leather, wood, comfort than the M5 of the era. Both cars are fantastic in their own right but also very different. We are glad to see you have located a donor engine. Keep us updated with the rebuild!

[@gregdettling6693]

@LTG I should quickly double check. We will want to find out what color of coolant to use by checking the VIN on the replacement motor as as to determine what color of coolant was originally used in that motor? The color of coolant in my existing engine that is still in the car has absolutely nothing to do with the color of coolant we will want to use? Just to double check and make sure. Also, painting these aluminum engines dark green or black is not such a great idea? From Greg In Canada P.s. thank you for this information about the emphasis on Luxury and smooth soft Ride quality that these are known for. The Owner at the shop I’m using said these cars have been very well thought out and refined. Great balance characteristics engineered into many aspects of the car just by looking at it, he thought.

[@vincentfarri3986]

Sir, Have you worked on a XJ8 Sun roof (repair/replacement)? Of so do you have a video?

[@LowTechGarage]

So far that’s one of the things that has behaved itself on the car. What are you trying to repair with it?

[@jameswhite9025]

Mine was purging into the overflow tank by the wheel at one point, turned out to be the expansion tank cap. $14 fix.

[@LowTechGarage]

Thanks for the info. We have tried a few new caps with no luck so far :( Maybe we will sources an OEM one just to be sure.

[@superpeluso1]

I have a 2001 xjr immaculate conditions with 98k on the miles I got the car from a consignment and the previous owner kept the car in the garage for 13 years and spent over 10 k in maintenance 🤔 my only problem is the suspension! I spent 2500 on everything bushings shocks brakes everything my only problem is that every mechanic it’s escared to change my suspension do annoying 🤔😂 in fact I had to replace the front shocks because they collapsed 😒…. I even offered my help and more money than they charge… huh people…… I still love my car I get lots of compliments every time 😉☝️

[@LowTechGarage]

That is a shame you cannot find people to help you work on the car, they are not that complicated. Great learning experience for you!

[@superpeluso1]

@@LowTechGarage yeah I know but I am very very mechanically inclined and I guess I have to fix my own jag in fact I just don’t want anyone to touch my kitty cat. In fact thanks to you I find out about the supercharger cooling pump didn’t know it had one ☝️

[@bensautter1605]

unfortunate luck, but should make for some great content!! The wife and I have a little camping road trip planned for next month so going to start this weekend on some maintenance. Planning on replacing the water pump and any of the rad hoses that look questionable. I was leaning towards replacing the secondary tensioners using the cheating method by loosening the exhaust cams but im starting to second guess that decision. Do you have any thoughts? Also have new Michelin PS4's that will be going on next week. my car is a 2001 silver over oatmeal with 90K.

[@LowTechGarage]

The chains and tensioners were replaced on our XJR ahead of us purchasing it. With the amount of effort needed to get back to the chains I would get in there and replace everything. Long term I think you will be glad you did that. We are running the same tires :)

[@flyurway]

Well that sure sucks! It's been about 7 months now, where does it all stand now? Adding all that boost, I know at least a couple articles I've read discusses overdriving the s/c beyond it's efficiency and it gets to the point you're just wasting power to make more heat, which costs still more power. I'm thinking you must be pushing that limit by the time you've replaced both pulleys. And yes, I know you've updated the pump and intercooler. Being a 4.0 I'm assuming the timing chains have already been dealt with? So as far as all this heat goes, have you looked at all into water injection? Seen a couple articles on that too and at least one guy that was overdriving the s/c on his 4.2 and he was swearing by his h2o injection, I've been wanting to look into it myself.

[@LowTechGarage]

Yes the chains have been done. The car still runs fine but under boost he issue persists. We are finalizing some work on the 59 chevy and then the proper dive into the XJR will begin. I cant have both cars down at once :(

[@kennethtyree4770]

Do you have a Mark VIII as well. If you love the XJR, you must love the Mark VIII too.

[@LowTechGarage]

Used to have a crown Vic

[@oldasrocks9121]

All this stuff will only make the car run weird unless you remap the ecu, you won't make significant hp gains just from physically changing components. Also, turbos boost, compressors compress.

[@LowTechGarage]

Thanks for the feedback

[@jameswhite9025]

Careful opening the exhaust too much, low end torque will fall FLAT on its face, ask me how i know. OPEN your bypass valve back up!!!!! Not a good idea in the least to not allow it to do it's job.

[@McJagR]

Have you thought of swapping the engine for the 4.2 xjr. I believe you use the bottom end and reuse everything top end from the 4.0?

[@LowTechGarage]

This is an interesting idea! Can we say project creep!!! :) Maybe we can build up a monster 4.2 for the ol girl in the future!

[@McJagR]

@@LowTechGarage definitely doing it to my xjr in the to be soon future! 172k miles the old girls days are numbered 🤣

[@cirquedumike]

I would never take apart my XJR just to removed some dirt.

[@LowTechGarage]

I wish dirt was its only problem! hahah

[@ashveersandhu1537]

I own a 1998 Jaguar Xjr since the car is lowered I ran over a speed bump too fast and put a huge hole in the radiator and I’m looking to get another radiator but another oem radiator is $900 how much is the radiator that powerhouse offer and how can I order one also how quickly can I get one

[@LowTechGarage]

Did you put a hole in the engine radiator or the supercharger radiator? You can get engine radiators from rockauto.com the powerhouse uk items can be seen at powerhouse.uk

[@stevenstern2079]

I know this video is kinda months old..just bought my jaguar but won’t go past 3krpm..any suggestions/help?

[@LowTechGarage]

This sounds like you are in limp mode. I would suggest plugging in a code scanner and seeing what comes up.

[@gregdettling6693]

@LTG this video is over a year old so your coolant issues are likely long since gone. I’m curious where you get your high octane gasoline from? Many people avoid gasoline from Esso up here. Also do you think changing the type of coolant would have helped? I think you have this all sorted out and fixed by now. :)

[@maxlindstrom5435]

Dis you get your water leak fixed?

[@LowTechGarage]

I am getting the Air Conditioning installed in the 1959 Chevy right now (videos coming soon) so I can drive that while working on the XJR. There will be a comprehensive video on removing the cylinder heads and everything involved coming as well.