Jaguar XK8 Vent problems, top coolant hose, dipstick holes and French special edition XKR/X100 V168

[@paulkane6645]

I know the vents are 100% functional because I was there. Under full thermal load (Max output + full A/C), the X100-R test car lost power due to inefficient Intercooling. Whitley designers refused to compromise aesthetics by adding a recommended ‘under-bumper’ grill for additional forced ventilation. It was a guy at Mira in ‘97 that discovered the test car passed when the Bonnet was left on the latch. Jaguar installed bonnet vents on the XKR but refused the same solution for AJ26-S in X308-R and later X204-R. In fact, all other models got ‘under-bumper’ grills. Few know that the first gen XKR had the smallest Grill area of any mainstream car of similar specific power and this is because it had bonnet vents to draw higher flowrates.

[@ODRModurol]

Paul, really interesting information. I stand corrected in my assumption and stories I have heard. Thank you very much for your input, regards Damian

[@paulkane6645]

@@ODRModurol I remember a lot of the back story. The extra grill or 'under scoop' solution was rejected flat by Geoff Lawson himself. The test managers argued that the '96 Buick Riviera was a precedent for an extra Grill/Scoop when adding a Supercharger/Intercooler but Whitley was adamant. There was even rumour of internal discussions that Malcolm Sayer would never have accepted the same 'under scoop' solution on the Series 3 e-type had he still been alive (which needed to cool a larger v12). Ultimately there were new vents fitted to the XKR but also Jaguar allowed some very discrete trimmings to the front bumper skin (in the mouth and above the front mesh) and in front of the oil cooler. This is why a 1997 front bumper actual differs to a 1998 front bumper! I believe that change was carried forward on both models.

[@jonathanslade2358]

Thanks for another interesting video, not sure about the orange mirrors, I've just got rid of my gingicators don't want to go back down that route! Cheers, Jon

[@ODRModurol]

Jon, fully understand where you are coming from. Possibly the mod was inspired by the gingicators.😆👍, regards Damian

[@jonathanslade2358]

Hello Damien, I've just watched the French episode again, I'm thinking of putting an xkr bonnet on my damaged xk8 I bought earlier this year so I'll have to make sure my coil cover seals are in good condition! I'm gradually buying all the parts I need for a front end rebuild just waiting for a front bumper mounting cross member that isn't too rusty! Great video. Cheers, Jon

[@giuseppe4909]

The vents are indeed needed for the supercharged versions due to somewhat higher heat in the bay.

[@ODRModurol]

Giuseppe, the vent are helpful for ventilation but also have a down side in this particular case, regards Damian

[@giuseppe4909]

@@ODRModurol agreed, but there are ways around it….try making an aluminum inner shield, attached with spacers….that will deflect the incoming water and still allow extraction of hot air

[@ODRModurol]

Giuseppe, one has done it yet, still looking, regards Damian

[@SuperchargedShift]

Great video! The vents on the xkr bonnet do seem to expell a fair amount of heat even sometimes a couple hours after the car has been off. I think they are more of an aesthetic feature rather than practical though as they are positioned further to the front of the engine instead of the middle, where the majority of the heat is.

[@Punisher9419]

When their is wind moving over the bonnet it will help draw the heat out from the engine bay I should think. Pressure difference type of thing.

[@ODRModurol]

KADUJI1000, I believe the bonnet press tooling had to have a engineering change after it was delivered to add the bonnet vents. This must have been because Jaguar hadn't committed to adding it at the beginning of the program. I believe the position of the vents was a compromise between the feasibility of the inner and outer panels of the bonnet and their function. Needed to maintain the formability & stretch of the outer skin and not interfere with the support structure of the inner panel. Plus look visually pleasing and are the best way to define the XKR from the XK8, thanks for your input, regards Damian

[@ODRModurol]

Agreed about the pressure difference and drawing out hot air. If Jaguar was looking at air flow etc why did they never add lower engine covers that most new car have today?

[@paulupham9438]

Hi there . I have a leak at the snap lock connector at the joint of the octopus heater hose on the passenger side of my 2004 UK XK8. I have found the part numbers and details of the little u shaped tool to open the snap lock connector . Are there any videos showing how to replace the octopus heater hose please . I can't find any.

[@paulupham9438]

I live in Oxford and looking for a good indie farage to fix .

[@ODRModurol]

Paul, sorry I haven’t done mine yet so I no video from us, regards Damian

[@Punisher9419]

The XKR's do get very hot, the vents do a lot to get rid of some of the heat but even with them the engines do get too hot and they have to retard ignition somewhat. You can see the heat comin gout of them even after a short drive. The intercooler pumps tend to fail as well so when that happens infition is retarded even more which is very common failure. An upgraded intercooler pump and intercooler radiator is a good way to prevent this and keep power up.

[@ODRModurol]

Understand the XKR does get very hot especially when drive enthusiastically. Interested in your observations about retarding the ignition to reduce power and upgrades to handle the cooling. It seems to me that Jaguar probably never intended the supercharger to be used on the XK8. In fact the bonnet press tooling had to have a engineering change after it was delivered to add the bonnet vents. Therefore, wasn't completely thought though at the time as there was a lot of demand and pressure to add the supercharger quickly. Thanks for your input and support, regards Damian

[@Punisher9419]

@@ODRModurol There where some talks on the forum and a person who did it but they improved the design somewhat by extending the bonnet upwards towards the windscreen so the air came in and out very easily although I dont' know what it would be like to drive in the rain or if you washed the car. It was a bit too open. But I think with an upgraded intercooler system mostly just the pump and radiator you shouldn't expereince any power loss. The pumps these days have all pretty much failed anyway but most owners won't realise this has happened because no codes will show up. You just loose power and throttle response isn't as good. The upgraded radiator is just about double or more the thickness. Just changing the pump though is a good enough upgrade which is well worth doing as it's about £120 or so.

[@ODRModurol]

Good info, much appreciate the feedback, regards Damian

[@garyvanremortel5218]

Remember several years ago when you and I went thru this issue together over a few weeks? What a disaster.

[@ODRModurol]

Gary, yes I remember, didn’t think it was a disaster, regards Damian

[@Ridley2907]

As everybody now checks their top hoses....... :-)

[@ODRModurol]

Matt, it was worth checking my hose this week, 😆😉👍, regards Damian