Hi Guys

Problem with 'Carmen' my 1995 XJS with 4.0L AJ16 Engine

Having fitted 6 New Injectors and did some other stuff, I finally managed to get the Engine to run but then disaster suddenly struck, as one of the Injectors was leaking round its bore

Sending a spray of Petrol all over the Engine which was running at the time, so very, very, lucky that She didn't burst into flames, while all the other Injectors were Ok

At which point I was starting to think that the Injector wasn't seating properly and that was the cause of the leak and so I took them all out, double checked for any 'crud' although I had thoroughly cleaned the bores in the Inlet Manifold

And then put all the Injectors back in and making as sure as I could that they were pushed home

But unlike the Injectors that are on the V12, where you can push them really deep into the Manifold, the Injectors on the Six still seem to wabble about when they are Inserted

Where since I'm not as familiar with the AJ16 as I am with the V12 engine, I was starting to wonder if I had pushed the Injectors in far enough?

Even though I'm pretty sure I've pushed them in as far as they can go

So please would you look at the photos and let me know if you think that I have done it right, as only the first part of the Injector seems to go in, rather than the Shoulder that is above it





The Injector only goes in far enough to cover the Silver Part from the Tip where the rubber seal is up until the beginning of the first shoulder

The Fuel Rail then goes on ok but in the following Photos, do the Injectors look as if they've gone in deep enough?



The Red 'X' is there to mark the Injector that was Spraying Petrol all the injectors have new rubber seals as shown in the first Photo but should they have any other seals apart from just that one rubber ring round the tip?








Do those Injectors look as if they are pushed into the Inlet Manifold far enough?

 

OB, between the rail mounting spots and the intake manifold should be no gap. Flush fitting. If the screws don't go in far enough, then the injectors aren't in far enough.

 

Hi Daim

The Injectors go in flush with the bottom of the First Step 'The Black Part' but none of the Black Part goes into the hole in the Inlet Manifold

But the Fuel Rail bolts up Ok

So does that sound about right to you?

 

Sounds quite right. I haven't got an AJ16 sitting here as a reference at the moment... But sounds quite ok.

 

Hi Daim

Cheers!

I'll Start her up Tomorrow and then see what happens

 

It's just the rubber oring that got distorted while you pushed the rail in, either on the rail or intake side, very easy to do, you'll need to remove the whole rail again, use a little rubber grease on the orings before you push them in, much easier that way. If you squashed it badly, you might need to replace it with one of your old orings, will be clear when you remove it.

 

Hi Katar

Cheers!

I thought it might be something like that but it was leaking from the Inlet Manifold end and the Rubber Rings on the end of the Injectors haven't had a chance to feel any heat and get bedded down

So I pulled it all to bits and did it again and so if its still leaking Tomorrow when I start her up, then I will try the rubber grease idea

 

you can use o ring grease or even a little bit of Vaseline or a dab of motor oil to lube the o rings. o ring lube is best. there is a bit of concern with using petroleum lube with natural rubber o rings but intake o rings should not be natural rubber. when you pull them out make sure none of the o rings are twisted and there is no nicks in them. you can try inserting the leaking one in a different hole and if the leak follows the injector or stays with the same location then you know that there is a problem with the o ring or the injector causing the problem. or a problem with the bore. make sure the bore is clean and free of any debris corrosion or burrs.

 

Hi Ezrider

Now you come to mention it, when I put my finger down the Bore of the Injector that was leaking, I could feel some ridges unlike the other 5 that all felt smooth but for some strange reason, I didn't think anything of it at the time!

But with the benefit of hindsight 'always a wonderful thing' I can imagine that the Rubber Ring Seal on the end of the Injector was getting hung up on those ridges

Though as the Fuel rail is all back together, with all the Injectors in place I may as well give it a try and see what happens as maybe this time I could get lucky and it won't leak at all

The problem being caused by my lack of knowledge of the AJ16 Engine and how the Injectors Seal inside those bores

If the Rubber Ring on The Rogue Injector gets hung up again, perhaps I can carefully hone it out smooth with one of those Mini sanding drums on the end of my Dremmel

What say you?

 

Try it as it is, don't go with the Dremel there, sounds too invasive for me, you'll get them in eventually. For future reference what you want here is Castrol rubber grease, plenty cheap on eBay and it's a wonderful thing for rubber

 

A dab of washing up liquid will do the job as well.

 

Katar@Daim

Cheers Guys!

It was only that one Injector that was giving a problem last time, so I'll give it a try and hope 'The Jaguar Gods' are on my side and I've also got a mate coming round later on to day who will keep an eye on things when I Start her up

 

 

glad you got it solved. always sucks when they send you the wrong parts.

 

Hi Ezrider

I'm not sure they did send the wrong Parts, as these New Injectors already had the Rubber Sealing Rings on them, where these Injectors were OEM Boxed and also heat sealed in Plastic Bags

Which were Printed Non-Returnable if opened

But the Seals on the Old injectors visibly looked a lot bigger and were a much looser fit round the Silver Probe but a much tighter fit in the bore

Also the New Injectors have made a very big difference when starting her up, as now she fires up with just a flick of the key, not that she was bad before but its instantaneous now

Now for the Bad News!

She has developed a mystery Oil Leak underneath that round Gizmo with the sight glass on it, that shows you Tdc

'The Saga continues'

 

I'd replace those o-rings while youre still messing around in there. I don't know the size, but someone must...

Order a set from ebay perhaps?

 

most likely there is more than one application that uses the same injector but may use a different size o ring and they just bundled both under the same part number.

 

Hi Ezrider

Having never thought of that, I think you could be right but the Seals off my Old Injectors look to be in 'as new condition' and as there is no sign of leaking, I am going to leave well alone