Hi Someday

The Engine in 'Lady Mary' sounded exactly the same as the Engine in 'Cherry Blossom' when the Crank Sensor got hit with the broken Alternator Belt (That sort of lost compression sound)

Not saying it is that but I wouldn't rule it out, as a possible cause of 'iffy' Starting

Also I'd change the Filter to see if that makes any difference, as it might be holding the Flow of Petrol back

 

Where did you source the pump from?

if you try to order it directly from Walbro website they do give this as a warning

 

Definitely changing the filter, but there aren't any broken belts, and I don't know how that would mean the pump itself wouldn't work when powered directly.
But thanks for the tips, as usual.

 

Spikepaga - that spelling error on the site you show doesn't exactly fill me with confidence. Apparently they're "an independent seller of Walbro fuel pumps and accessories." However, the pumps with the "exteremly" high counterfeit rate appear to be the high-flow performance pumps, which I do not need.
Also, that site shows me what appears to be the external fuel pump as fitting a 1992 XJS. That is wrong.

 

SDSD

I would get your mechanic to check connections WHILE he is messing with that tank access lid.

This is the Parts book drawing for your car.

#9 plugs into the lid, on the outside, and the other end plugs into the car loom.

That pigtail on #2, is the connection on the underside of that lid, and that is where the Sedans had major pump issues, as in bad connections.

Not saying your pump is bad, but with tank out, only a few seconds to ensure the integrity of those connectors, top and bottom.

 

I've actually already ordered the pump from eBay, so I guess it's coming, needed or not, but I will certainly ask him to check the connections once he has the tank out.

 

Just an update, or a "situation solved" post, really.
A couple of days ago, she was all fixed. They replaced the fuel pump, the fuel filter, and the fuel relay just to be on the safe side. She fires up pretty-well instantly now. Yay!

There is one odd thing, though. The fuel hose bringing fuel to the engine was also replaced, and the garage said that there was a rubber grommet thing inside the attachment where it goes onto the rail, and even though they tightened it, it still needs a slight tighten regularly. They said that after a couple of days it was pretty solid, but after two days of using the car, it's needed a slight turn, just 10-20 degrees, each morning. This isn't normal, surely? Understandably, the idea of it not sealing well and leaking fuel onto my engine is not an idea I am happy about....

This is the hose in question:

 

It is where the hose assembly attaches to the fuel rail, or where the rubber hose is attached to the steel part of the hose assembly that is rotating? Usually where the hose attaches to the rail is a steel against steel taper that should sung up and be leak free.

There are fittings where there is an O ring, such as into the fuel filter, but there is a stop where it can't be overtightened and crush the O ring. I don't see any washers or O rings called out in that joint in the parts book, but there is in the fuel filter and tank connections. Something isn't right.

Take a look at this hose kit and click for the detailed image, the usual connection is the one in the bottom left corner, it has a mating taper on the fuel rail https://www.motorcarsltd.com/eac9986.kit.html I realize this is the prior hoses to what you have, but the taper style connection is a standard Bosch type connection, my X300 saloons use the same thing ( as well as Mercedes)

 

It's the nut fastening the actual assembly to the fuel rail. I'm going to go take a quick photo.

 

Photos I took just now.

This is the connector. It rotates about 10 to 20 degrees. Tried twice, before starting the engine when it was cold after a run the previous day.

Connector circled


Should this left nut be flush against the big connector nut to the right?

 

The nut should not be flush. The joint is one of 3 types. The tapered I noted in the link above, on the left is a brake line type flare, and on the right an O ring. The O ring is grey, so a bit hard to see.
I've not seen the flare type on the Jaguar, but it's common on other cars for fuel lines. The way the nut sits I suspect it's either flare or O ring. Does it leak if it isn't tightened up?

The flare is a metal to metal seal, so the nut will come to a definite stop when it's tightened and you'll know it. The O ring will compress to a certain extent, but again there is a stop to prevent over compressing the O ring. It's obvious when doing up the joint when it's tight enough. Worst case, I wonder if it's cross threaded??

 

Thanks for that. Going from the end, I don't think it's cross-threaded, as the nut does move smoothly when I give it that little turn. There's no unusual resistance from there. It feels rather like I'm compressing it against a rubber O-ring indeed. It feels tight each time I finish tightening it--and I'm careful not to put too much torque onto it, and use a spanner on the fuel rail side connector as well.
I don't know if it leaks if not tightened, as I'm checking it regularly.

Checked with an older photo of my engine, and even before the new hose, the connectors weren't flush. For all I know, the original could be moved around/tightened.

 

Hi Someday

Unless your Facelift V12 Car is different?

The Pipe that you have Circled in your Photo, is Not the Fuel Supply Hose but the Return Hose, as the Fuel Supply Hose is on the other side of the Car (The Drivers Side on a RHD Car) at least it is on my Pre-Facelift V12

 

OK, being at the change point, you have the later rail, AND the 2 fuel pipes (supply and return) are on the LH side of the car. The earlier cars had a supply on the RH side, and the return on the LH side.

This parts drawing clearly shows 2 (TWO) o.rinsg per pipe/hose assembly AT the rail. They will require NO tightening as you drive IF they are installed PROPERLY, One seal fitting TO rail, 2nd seal, fitting TO pipe end.

They are the same design as A/C fitings, and we dont mess with them as we drive, well down here we dont.


#9 and #13 are the seals in discussion here.

 

Oh-ho. So instead of putting both seals on the hose end and ramming it onto the fuel rail, put one on each end and then tighten? I shall definitely check with the garage to see what they did. If they didn't do it right, I shall get them to correct their error.
Very useful tip, thanks Grant.
Wonder why it makes such a difference? The one that should be on the rail not getting pushed in far enough or something?

OB: You're technically right in that the return fuel rail does come off the starboard fuel rail, but then it swoops under the a/c compressor and you can see it very clearly in that photo of the older setup. It's the grey-green metal pipe to the left of the fuel feed.

 

Seems like you trust these guys, but I think that with our cars, when they are being fixed or parts changed, we have to try and commandeer all operations. You have to tell them what to do specifically versus letting them diagnose too much. I have not gone to my 110 dollar per hour Jaguar specialist now in a couple of years, but rather to a “regular” mechanic for my cars (1/4th cost), but I typically search forums, TSB’s, correct parts and procedures ETC and I tell them what to do. Just as an example, recently I got my Transmission mount replaced for 50 or 60 dollars in 30 minutes. They where trying to tell me what order they though the multiple pieces went and they could just not believe anything was that over engineered...........and I was like ““thanks, no, please install them this way”” ....., and I stood there while they sandwiched all the parts on a pressing machine, and installed it in the car....of course it all worked out......at first taking this approach was awkward, and it felt strange being the know-it-all owner telling them what to do, but now they love me there because when they see one of my cars pull up they know there is little to no diagnosing involved and I already know what needs to be done in exactly what way.

My point is, try to stay in charge and control of what is happening, these cars require lots of owner involvement in that way, and even if someone else is doing the work, you have to become mechanically inclined, unless you have a Jaguar specialist ($$$$$$$) you are taking the car to, who knows all the quirks and eccentricities. A well meaning mechanic can create more problems replacing things he does not know how to replace properly. I would suggest next time he consults with you before changing anything, you do your own research on parts and procedures and then make the decision yourself.

 

Well, I basically trust professional mechanics more than I trust myself. I could learn the technical issues to be aware of, but actually doing it would probably take way longer, and I just don't have the time. And they seldom do it wrong, and their prices seem reasonable. While not Jaguar specialists, they are high-end European specialists at least.

However, I do try to gather as much knowledge of the quirks and eccentricities as I can, using these forums and other resources to try and get an idea of what is involved, writing it up and translating it into Japanese, and discussing things with the head mechanic. I just didn't expect a simple ("simple") fuel hose to be weird.

 

If yours is one of the few or only old English car at that shop, I feel for them, Lol. The Germans usually make more rational decisions. They still over-engineer, but it seems with them it “makes sense” . Jaguar, specially old Jaguar, does not follow that approach.


”Simple things made weird” should be a bumper sticker we all place in our XJS cars.

 

Indeed. If I were to disgrace Her Ladyship with something so crass as a bumper sticker, something along those lines would be most suitable.

The shop's main speciality is Italian stuff, so I assume quirky is something they're well used to....

 

Here's an interesting issue. I called the garage, and they said that they didn't find any O-rings on the old hose attachment either, only the same green rubber ring about 1 cm deep that came with the new pipe. Could this be a facelift change? I wouldn't think so, as Jaguar Classic Parts has the O-rings right up to the final six-litre. But why would the original hose also not have had any? Perhaps I should get some to be on the safe side....