Fun and games with the XJR... And then....disaster strikes...!!! 
Sunday, August 13, 2006, 12:00 AM - Maintenance
Todays challenge, should you choose to accept it.... is to work out from the following symptoms the cause of our breakdown last friday....

Previously behaving perfectly normal (the Jag, not us!), we left the restaurant to return home (a 3 mile ride), having just turned over the magical 99,999 miles on the odometer !

Engine turns over normal speed, but will not start... feels like it's trying, just can't make it to run by itself. 1/3 tank of gas left. Sudden breakdown, so maybe condensation in the garage got to something (hadn't been run last few days)? Checked electrics, relays, fuses, all seemed okay. Let it cool down a bit (guess around 150 under the bonnet !!!) Still no joy, same sound like it wants to go but can't.

Loosened fuel rail regulator pipe on engine, no gasoline coming out. Strange, fuel pump can be heard running after ignition is switched on... Must be something nastier, time to call AAA auto club for a tow... good thing we're so close to home.

Saturday... instead of going to the car show, we've started detailed diagnostics... Still no gas getting to engine. Son turned on ignition, can hear fuel pump whining, then shuts off after a few seconds of non-starting, just as it should...

Can't have been something nasty in tank, filler cap is automatically locked by security system...

Maybe gauge is broken, no gas in tank? Removed Trunk Tank trim panel. Nope, releasing the seal slightly on the sender unit looses a flood of gas. Maybe filter 100% clogged? Under (jacked up and stand-ed) rear left of car, release fuel filter inlet pipe, dry. Son turns on ignition, pump runs, no gas... Hmm, puzzling. Not pumping gas, but if defective would make no noise....???

Searched Jag-lovers web site and Alldata and Mitchells CDs, no clues there... this makes no sense.... I really DON'T want to have to take out fuel tank (maybe 4-6 hrs work if goes smoothly, and I don't have the special fuel pipe release tools either) and anyway, if the pump is running, it's not that, is it ?

Maybe the fuel pump inlet filter is clogged, that'd explain pump running but no gas... or maybe the pump's internal overpressure bypass is jammed open, but surely there'd still be at least a dribble of gas, not absolutely dry pipe...???

Brainstorm... supercharged XJR has 2 fuel pumps, 2nd one controlled by a black box in the forward area of the trunk next to its relay, below the tank itself. Hmm, maybe I should hotwire it and if the filter inside the tank is clogged, fuel still won't come out, right? Traced the wiring, removed the 2nd pump control module (black relay box) and grounded the pink relay wire. Now 2nd pump whines and runs with ignition on, floods garage floor with gas... hmmm....WTF is going on here? (hey, have to remember that trick if the primary petrol pump ever fails in the future.... I have a limp home standby in the tank!!! I'll write this up on another page)

Okay, looks like the pump must be somehow defective, almost resigned to taking the fuel tank out.... siphoned out rest of tank contents, maybe 8 gallons. Opened and removed fuel sender unit. Looked inside, and all becomes clear !!!!
(Spoiler here, don't read unless you want to know the answer !!!)

The rubber pipe from the pump to the y-connector exiting the tank is off at the pump and just hanging there in mid-air, hose jubilee clip and all !!!!

Hmm, that's a small opening, the pump is about 4-5 inches away inside and to the left, how do I get that pipe back on and tighten the clip ???

So I rigged a coathanger wire to go around and hook the pipe back into position, then added a gardening tool that looks like a long snake tongue with a V in the middle to hold and jiggle the pipe from the front back down onto the pump outlet tube. As you can imagine, that took maybe half an hour to do, while laying inside the trunk in a foetal position... so much fun...

But still better than taking the tank out...

Okay, so the root cause? Maybe the fuel filter is clogged and the pressure built up and popped the pipe off? So after an hour of fighting with it I came to the conclusion that the filter outlet pipe is permnently welded with the aluminium filter casing, no way it was going to let go, even with the fitting rounded off by special fule line wrench that goes 90% of the way around it.

Off to Autozone, picked up a Dorman 800-153 quick disconnect fuel line repair kit, which is basically an 18" long 3/8 in. metal pipe with the correct filter connector and a brasss compression joint to join to the original fuel line. And a generic pipe bender (impossible to bend fuel or brake pipe without kinking it otherwise) and you'd also need a small tubing cutter (no hacksaws allowed as shrapnel getting into the injectors upstream of the filter is a huge no-no !!!). Yeah, buy two of those repair kits, you'll probably mess up the bends or kink the first one, you can always take the spare one back later if you don't need it...

So replacing the fuel filter, which I bought months ago but put off (wise decision as it turns out) was finally done.

By the way, I blew through the filter and gas went flying out the other end so it wasn't clogged at all...!!!

I guess it was just uncle Murphy (y'know, Lucas's twin brother) playing around again, and I was just lucky to be so close to home !!!

Guess what, a new player in town.... NipponDenso, Prince of Famine ....LOL

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Simple fix for bad vibrations....duh !!! 
Friday, May 5, 2006, 03:42 AM - Maintenance
Well, I'll be darned... it actually paid off to be methodical and persistent for once....

Remember I had a vibration problem that I was sure was the propshaft Center Bearing?

Well, I spent another two hours under the Jag yesterday, and this time put it up way high on proper 6 ton axle stands (those I trust, unlike the 2.5 ton cheap ones I had before) Found a good use for them though...used the cheap stands as chocks in front of the front wheels....perfect angle to prevent movement.

Ran the engine, switched off the Traction control, and put it in drive. revved it up to 45mph with a piece of 2x4 on the pedal, and got the vibes again....

So taking my life in my hands (actually with the stands and a 3 ton jack under the rear axle I felt pretty safe) I got underneath the car.... felt the vibes to be coming from mid-underneath, but with little load, minimal compared to being on the road. But it's probably the bearing or prop out of balance, so I affixed an old lead fishing weight to the prop with a thick plastic tie... that'll be a good test.

Whoah! the vibes come in horrendously at 30mph, but there aren't ANY at 45mph. So it IS the propshaft!

Back in the garage and up on the stands...

So I took my trusty screwdriver and held it to the body and touched it to the prop just south and north of the center bearing. hmmm, slightly oval track there, touches more in some places, less in others.

So shut off the engine (oh yeah, I did have a huge fan running in the garage(bad eough having to deal with farts, let alone carbon monoxide poisoning) and get back underneath. I have a nice fresh steel scratch around 80% of the shaft, and black paint on the rest.

So I thinks to myself, I remember how the old guys used to do this in the England, and I put a Jubilee clip (that's an adjustable hose clamp to you yanks) around the prop and clamp it down with the bulk at the painted area, after all, that's where it's the lightest.

Guess what, no more vibrations!!! I mean it's perfectly smooth now from 0-80 with no discernible vibes from underneath. Guess the weight was just a lucky guess, although I could have used more clamps....I remember seeing a prop with half a dozen clamps on it one time...

Yes, I still have the clunkclunk from underneath on hard 0-20, but that's okay until I get the money together to replace the exhaust (already bought the bearing), but have to cut off the rear exhausts both sides as they're all welded together by good old Michigan rust.....not a job I'm looking forward to....maybe I'll just put that off until I retire...
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Brakes now work..... 
Tuesday, January 31, 2006, 09:48 PM - Maintenance
Okay, worked on the brakes and bearings last weekend.

Bought all parts from: AKA Auto Parts Place Seemed like the best/cheapest place with free shipping (I knew that'd be substantial on discs pads etc!) Surprisingly they delivered all the parts within a few days from a variety of different locations, and thay all showed up within a week and were correct!!! Can't do better than that.... Judging by the site and shipping they're a partner of the Worldpac/Carquest Group. Excellent service.

Discoveries - Need 7mm short Hex Socket to get the caliper slider pins out. Difficult to use other tools as limited accessibility due to brake pipes/speed sensor wires etc.

Changed both front brake discs as showing uneven pad transfer, accounts for tremors under heavy braking. Brembo discs Their part number was JLM 20341 for the front discs.

Installed new Akebono Brake Pro Ceramic pads front and rear: ACT394A and ACT688. Perfect fit, very good quality pads with special shims and moly lubricant, but expensive....

Installed new wheel bearing set on R/H front as looked somewhat worn and felt like some particles in the grease. Part SKF BR8 outer/ BR17 Inner bearings in a kit K8020-37040 complete with inner seal.

Changed front brake hoses for MNA 5680AA just as a precaution (10 years old) and to make sure pedal is firm. Bled brakes through all the way with Synpower Fluid. Think it's the best on the market.

When changing hoses, I noticed BOTH the braided wheel hub grounding wires were broken, so I reconnected one and replaced the other with some high-flexibility Iron flex ("_"). Hope that'll work for now. Probably non-essential, but this works the opposite way too... if Jaguar felt it wasn't necessary, they wouldn't have put it on there in the first place.... have to get some braid to fix this permanently later...

What a difference. Much smoother low speed braking and driving, with no shimmying. Pads bedded in nicely after frying them a bit on the recommended high-speed fast stops with lots of heat, then gentle cooldown, and they seem to be reasonable when cold now.

Still need to change the propshaft Center Bearing as I'm sure that's where the acceleration clunking and vibration at 50mph is coming from, but that's going to be a pain in the ass as it's right above the exhaust joint to the rear mufflers (which of course is permanently welded by rust).
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