Previously in Project XJ6, we played with wheel choices and slapped on some used tires in anticipation of the Jag’s first road test. This week, we’re hitting the road to find out how it performs – both under its own power, and (ahem) manually.
Since the car had been sitting for a couple of weeks, I wasn’t terribly surprised to find it needing a few things. The battery was dead, for starters (no pun intended); and both of the un-replaced tires were low on air. The latter was easily remedied with a quick application of compressed air, and the former cured by hooking up the battery charger for a few minutes.
But when I went to turn the key, it was the same old story. Rrr-rrr-rrr-rrr. Despite having left it with a couple gallons of gas, it seemed that both fuel tanks were again empty.
The previous owner had warned me that one of the tanks was a leaker… but which one? I grabbed a can of gas and decided to find out.
As I poured into the right-hand tank, I could see the gas running out the bottom as quickly as I was adding it. Clearly I’d found the problem tank, so I moved on to the left-hand tank and poured in the remainder of the gas (about 2 gallons).
But as I returned from putting the can away, I noticed that the left tank was also leaking. It was a much slower leak – maybe only a couple drips per minute – but it was surely leaking. Add one more thing to the repair list.
Given the slow rate at which it was leaking, I decided that a quick road test would be alright. After all, I still didn’t have an accurate picture of the car’s mechanical condition. There’d be no sense in replacing tanks, fixing exhaust, buying tires, etc. for it if larger issues were looming… and the only way I was going to find out was by driving it.
So I hit the road, exiting my eighth-mile long gravel driveway, turning onto the highway, and almost immediately getting off onto a tarred two-lane county road. It was my usual test drive route for new vehicles, which provided a nice 2 mile stretch of mostly uninhabited road, perfect for playing with unfamiliar cars.
I was surprised by how well things were going. Aside from the usual symptoms of an engine that’s gone too long without a tune-up, it ran quite well. It was a relief to see that the transmission shifted properly. Getting up to speed was easy, and in fact, speeding was a little too easy (70 felt like 50).
Though it was no stoplight drag machine, it could accelerate well enough for everyday traffic situations, and it cruised along nicely at reasonable RPMs despite having no overdrive. The brakes were good, the steering was straight – but I did notice a rattle somewhere in the front end which will require my attention.
Things were going so well, in fact, that I set aside my better judgement and decided to take another lap. I would come to regret that decision.
As I was returning from my second and final run, trouble struck. I was about a mile from the shop when the engine began to lose power and wanted to stall. I was able to coast, more or less, down the shoulder as the engine finally stalled. There wasn’t much gas in the tank… could I have run out?
So here I was, half a mile from the shop, with a dead Jaguar. It was Sunday. No one else was around. Therefore, it was up to me to resolve the situation.
I walked back to the shop, all the while planning my next move. I’d start the Suburban, hook onto the trailer, and use it to tow the Jag back. Sure, it was overkill for half a mile – but with no one else to assist, I needed something that didn’t require a second operator.
Unfortunately, that plan turned out to be a bust. Someone had parked a snowblower in front of the trailer, where it was now glued in place by 3″ of ice. Tugging the blower out would have ripped it apart, and any means of melting the ice would have taken too long. So that was a no-go.
What now? There was only one other choice – the tractor. So I hopped on, fired it up, and drove it down to where the dead Jag sat. The plan was to tow it back with a strap, using the seat belt to keep the steering straight, and moving slowly so as not to allow the Jag to roll into the tractor.
But that didn’t go so well, either. Despite my many efforts, the belt just wasn’t able to keep the car on a straight course. I’d have to go 10 feet, correct, go 10 more feet, correct, and on and on. After 60 feet, I decided not to continue.
What was left? There was only one option – the manual approach. I parked the tractor near the driveway (in an effort to slow down traffic), put the Jag in neutral, and began pushing.
The car actually rolled pretty nicely. That’s not to say it was an easy job… but in the end, the car was off the road and back at the garage, so I guess I can’t complain too much.
After taking a few minutes to recover from my extended period of exercise, I grabbed the empty gas can and went to town to refill it. When I returned, I went straight to refuel the disabled Jag.
As I popped open the gas cap, I heard a “whoosh” as air either entered or exited the tank… a bit odd, I thought. I then proceeded to pour the gas, and started the engine without incident. It was allowed to idle for a few minutes (so the battery could recharge a bit) before I hopped in and attempted to drive it into the garage. The idle sounded fine – but when I tried to accelerate, it was once again lacking power.
On a hunch, I popped open the gas cap again. Whoosh! Then I went to turn the key – and it ran fine. I drove it into the garage, now having a good idea of where the problem lay.
That evening, I did some reading. Turns out it’s common for the evap check valve on these cars to become clogged, which could cause the symptoms I’d been seeing. I decided that I’d look into it when I arrived at the shop the next day.
Upon my arrival that morning, I noticed my 1-2 drips per minute from the left tank had turned into a drip every couple of seconds, with an accompanying puddle of gas below the car. Again I popped the cap – “WHOOOOSH!” A large amount of air exited the tank, and the drip slowed back to its usual rate. I began to suspect that this lack of ventilation had not only been making the engine stall, but could also have been a major factor in creating the tank leaks (causing them to expand and contract which, along with the rust on them, led to their eventual destruction).
So I pulled out the evap check valve and attempted to blow through it. Sure enough, it was plugged from both sides. It is apparently a common temporary fix to puncture said valve inside when it becomes clogged. A few seconds with the cordless drill, and the “repair” was done.
Afterwards, I checked several times throughout the day to see if pressure was building, and ran the engine a few times to ensure that the problem had indeed been resolved. So far, so good!
So, what’s left to do? Clearly it’s going to need at least one new fuel tank (which means I need to find at least one fuel tank), along with an evap check valve, and a general tune-up. The front-end rattle needs to be addressed. There’s also the issue of the cut exhaust, which needs to be sleeved.
Once all that’s done, I can replace the tires (recently quoted at around $350 for a set of Uniroyal Tiger-Paws – less than I expected), deal with the separating headliner (a minor annoyance), and handle other appearance issues.
I’ll also want to try and find whatever parasitic load keeps managing to kill the battery… or cheat and install a cut-off switch, since I’d have to leave it sitting for a week or more before the battery would be too dead to start the engine.
The list has been made. It’s time to get to work!
As always, there’s more to come next week as Project XJ6 continues. Be here for it – same cat time, same cat channel!
Beautiful place where you live. Enjoy it! And, a little exercise never hurt anybody even on a cold day.
What? You have an older British car and DIDN’T expect to have to push it at least once? (lol).
This was going through my mind the moment I started reading 🙂
Reminds me of the 1972 Triumph TR-6 (motorcycle, 650cc, single carb, think it was called a Tiger that year) that had a clogged vent on the gas cap. First time I took it out it started stalling out on me about five miles from home. Just on a first hunch, while still moving I unscrewed the gas cap. “Woosh” and the engine picked up, rode a bit more, turned it around, and had to pop the cap three times while in motion to get home.
Happily, I had a spare in the parts bin.
I had a similar problem with a Volvo 240 breather (flame trap) that I “fixed” with a drill. After chasing oil leaks that were caused by pressure build up. I had a motorcycle tank repaired by a coating/sealer on the inside of the rusting tank. It was years ago, I don’t know what product was used, but it still does not leak and no rust issues in the fuel. Does the rear defroster work to keep your hands warm when you push it, it could be a big help in the future.
Oy. I’ve had to sally forth with the tractor a few times myself… last time I remember, we were in the ’98 Grand Caravan and drove through some heavy slush, some of which must have splashed up, causing the serpentine belt to throw itself. That was about a 5 mile tow home, and a 15 minute fix once we got there.
A car’s fuel tank and fuel lines are the great unappreciated systems that almost never require attention. Makes for a real problem when they go bad. And your Jag’s double tank system doubles your fun when they do.
ECV and fuel tank needs immediate attention, otherwise engine and tranny were OK. Sounded the Jag will be ready to run once the fuel delivery system is updated.
This doesn’t really add up. If the evap system was plugged there would be a vacuum created in the tank. The leaking getting slower when the cap is removed would indicate that pressure had built up in the tank. Vacuum in the tank could cause the car to starve for fuel but pressure in the tank would not cause it.
The running engine would create a vacuum that would slow fuel flow. On the other hand when it sits evaporation and temperature changes would cause pressure in the tank. I think that both are happening at different times. The whoosh probably sounds the same for either when the cap is cracked.
Quite a popular thing here was to pull the english donk (especially the 5.3) and insert a bulletproof GM 350.. just add fuel ..and head for the sunset
We have many stuffing the Ford in as well. I remember seeing an Espada for sale with the 351 a while back. Good to see the correct usage of the word ‘donk’.
A maddening problem. Thankfully you seem to have identified it quickly.
Why not just bring back a jerry can full of gas?
I kinda wondered that myself
There was a good chance the problem wasn’t lack of fuel, as it sounds like Keith thought it seemed too early to run out after only a handful of miles and 2 gallons.
Sounds like the resuscitation is going fairly well so far Keith.
Wow, I more fully realize how unprepared I’d be to take on something like this. My compliments and continued interest are yours.
I inadvertently caused such a problem on my father’s GMC dump truck. I found on the job site that it was missing the gas cap, so I cut a pop can in half and stuffed the can bottom onto the filler pipe. On the way home I ran out of gas…a mysterious occurrence since the tank had plenty of gas in it. In the course of futzing around with it beside the road it occurred to me to leave the pop can off; the truck started and I made it home without incident. Apparently the can had a good enough seal on the rubber gasket around the filler neck to draw a vacuum that even the electric fuel pump on the Jimmy couldn’t overcome.
Ventilated vs. unventilated gas caps. I can only imagine how many unsuspecting people went through the saga 20 or more years ago, back in the days when it was common to find both styles around (some of which fit interchangeably).
Classic crudded-up fuel system symptoms. It took me two days to drive the three hours from Crane Hill, Alabama with my 1963 Ford Fairlane.
The tank was pretty corroded but the sediment in the filter stayed at the bottom as long as you didn’t let off the gas once you got on the road. I made that mistake when I got to Huntsville for a break instead of driving all the way back to Nashville. Damn thing bogged down and died as soon as I got off the interstate. I didn’t bring any tools with me (mistake #2) and was wondering why there was a replacement fuel filter in the back seat that hadn’t been installed.
$250 for a new fuel tank and $30 for a new pump… runs like a dream.
I’ve pushed many a car in my day…I feel your pain. It’s great for the calves though.
You may need to check into the return valve system for the Jag. There’s two separate valves that regulate the return lines. If the wrong one is open, it will cause one tank to overfill while the other tank ends up dry. This is in addition to the valve that selects the active tank to draw fuel from.
Went to a Brit car show at the Gilmore Museum today. Admiring a Mark III XJ6, I asked the owner if he heard a “woosh” when he opened the gas tank filler. “yes”, he said. His tanks also leak. His car has never left him stranded like Keith’s did, but he is getting a significant pressure build up in the tanks.
So, I told him about Keith’s project car, and that he found what was causing the problem, but I couldn’t remember exactly what the cause was. Hope he finds this column.