Are these circled ports vacuum ports? Never had the lid off the supercharger but I would assume they could be used for spraying intake valve cleaner into.

 

You can unclip and use the vacuum line I have an arrow pointing to.

DC

 

Probably is already written about, which product you recommend for that service?

 

Seafoam works ok, but CRC valve cleaner works amazingly well on my truck.

 

Yep, I have used that spot three times now with CRC Intake Valve Cleaner.
It's a connection point for the brake vacuum hose and the other end runs into the back of the SC down low.
Dead easy to access and works a treat.

 

I was investigating this some time ago and saw warnings about putting any cleaning agent upstream of the supercharger for fear it would damage the coating on the rotors. I have yet to try the process.

On the V6 that looks to go to only one bank (plus the symposer). Does it go to both banks on the V8?

 

I assume you run the car while spraying?

 

As I said I have done it that way three times now with zero problems and no hint of any SC damage. And the feed into the back of the SC is for the whole SC (ie the main body of the SC) and nothing to do with any particular bank and nothing to do with the Symposer, and the V8 is the same as the V6.

 

Yep, you have to run the car, it can't be done any other way.
I joined up two of the long plastic tubes from my oil extractor vacuum pump, pushed one end over the spigot in the brake booster hose connection (it fitted just right) and fed the other end up into the cabin through the open driver's door window, where I then sprayed the contents of the can of CRC into that end of the tube (again the spray "stick" on the can fitted nicely down into the tube). This enabled me to sit in the car and operate the go pedal while spraying the treatment, as it calls for constant 2,000 rpm and then some 3,000 - 3,500 rpm bursts once the can is empty, and as the spray takes effect you need to give it a little more go pedal from time to time to prevent stalling. Possibly easier with two people, one in the engine bay spraying and the other in the driver's seat operating the go pedal, but I found it easy enough to do on my lonesome using the plastic tubes. Maybe a little more difficult for a LHD car which could need slightly longer tubes but I suspect the tubes which come with most vacuum pumps (eg Mityvac) would be long enough.

 

Is there a reason to use this method rather than adding a product like Redline Engine cleaner to the gas? I would be concerned about a product getting sucked in somewhere that could mess up the engine or one of the other million parts in this compartment.

 

Yes...The reason you are doing this is primarily because the fuel spraying in, is via Direct Injection, so it goes right into the cylinder and does NOT clean the backs of valves or top end of engine. This is actually the main reason to even use this method...Because fuel treatment has NO effect since (unlike port injection) there is no fuel going over the parts that need cleaning.

DC

 

Funny enough, I just did this for the 2nd time since I have owned the car. I like to do this at least once per year as I normally do 2 oil changes per year. You want to do this right before you change the oil as well, so in case there are any contaminants that get collected in the oil, you can flush that out. Most recently, as a one time experiment, while I doubt there will be much benefit to this, seeing I use Liqui Moly oil, I went ahead and used one of their oil flush products too. So basically, first ran the CRC cleaner (as previously described) and then the oil flush, prior to changing out the oil after the one hour heat soak and 10 minute highway run. I will be sending the oil out to Blackstone as well, to see what they see.

As for the process I used, very similar to previously posted. I have a long tube that runs from the brake vacuum line into the drivers side cabin and can spray and hold throttle at the same time. You will get some flashing Check Engine during the process, but it goes off normally. Very common. Also, once done, please make sure to do the heat soak as directed. That is where you see the most benefit from, prior to burning off the remaining during the highway drive.

Also, for the first time, I am switching to the new Liqui Moly Top Tec 6600 series oil. Still meets JLR spec, but added protection for timing chain wear, which unfortunately the AJ133 engine is known for. Thankfully I am out of warranty and never have to put Castrol oil in my car again.

 

I did this first time around a month ago using the CRC intake valve cleaner and the brake vacuum hose, and now that I had to remove the supercharger to replace coolant pipes, I noticed the brake vacuum hose indeed only goes to just one side of the intake. I'm pretty sure it's the same on the V6. Furthermore, when looking at the intake valves, the ones on the brake vacuum hose side are noticeably cleaner, so I'm not sure if the cleaner even made it to the other bank. Here are a couple of examples with ~17k miles:


Less carbon near the brake vacuum hose connector.


More carbon on the opposite bank (note the open valve).

I did some gentle manual scrubbing with the intake valve cleaner and was able to remove some carbon, but in future I think I'll look into spraying the cleaner to the throttle body instead. Or perhaps half a can to each side of the intake now that I deleted the symposer and could just use the symposer intake connection to reach the other bank...?

 

Hmm, interesting!
I may have to rethink how/where I apply the CRC cleaner in future.

 

Did you identify a better place to apply the CRC cleaner? I've been thinking about having a go at this myself, but slightly apprehensive about doing it

These instructions on BG's website seem to correlate with the left of the two ports highlighted by OP. BG instructions

 

See post 19 on this thread

https://www.jaguarforums.com/forum/f...intain-267485/

Two good videos showing BG fuel cleaning. I opted to have the dealer do this, but the process is still the same

 

Funny you should mention that, only yesterday I had a little poke around the engine bay looking for a better place to spray the CRC (as in accessing both sides/banks) but still easy to do).
Best I could figure out was to undo the clamp on the right hand side air intake tube (where it goes into the centre Y piece), pull the tube slightly off, poke a thin tube for the CRC into the gap, then maybe tighten the clamp up.
Dunno if it would work, haven't tried it yet, but will test it out before the next oil change (due in July/August).
On other sub-forums (XF, XK, XJ) some owners have drilled a small hole in the middle of the intake tube Y piece, sprayed the CRC in there, then plugged the hole.
I don't like the idea of drilling a hole in the intake tube as I'm not sure how to properly plug it up again.

 

A screw with an o-ring or silicone should work.

 

I don't like the idea of drilling holes either - if you go ahead with the air intake pipe let us know how it goes

 

I commented earlier in this thread, however having recently had the supercharger out of the car, I was able to get up close and personal with the valves to see how they looked. Car currently has 34k miles on it and as I previously mentioned, use CRC once per year. Other than cylinder bank 1 (for whatever reason) the rest of the valves looked amazingly clean.