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The old 88' starts and runs a tad rough! vid inside
Lots of moisture comes out the exhaust. I went through the whole fuel system first and cleaned it. Maybe it never dried out fully... but that was a couple months ago. I used a bottle of heet to remove any water but I've also read that can actually suck moisture into the system. The bogging down could be from low fuel... not sure how much is in there, but the rough idle and multiple cranks to start obviously it needs some tinkering. The wires on the ignition coil look crap and some of the injector wires look rough too... the plug wires and cap look fairly new and ok but I'll change them eventually soon. I did rev it hard the other day and got a small backfire upfront somewhere, so I'm wondering if the timing is off a little? Which might explain the difference in the left and right side pulses? This cars intimidating to work on. The engine is huge, gets warm real quick... and mine is smoking and backfiring a bit... ha
as you can see a little bit from the second video... the engine idle seems like the whole engine is a bit shaky. I've always heard something about a smooth **** locomotive like engine. 😬
Yeah the first time I popped my own hood out of necessity, I cringed. The folks who know what they are talking about will be along to offer some guidance.
But hey, she starts and runs!
And yes, they are incredibly smooth and quiet, especially at idle. Even after years of ownership, I'll find myself checking the gauges at a stoplight just to make sure it's still running.
Yeah the first time I popped my own hood out of necessity, I cringed. The folks who know what they are talking about will be along to offer some guidance.
But hey, she starts and runs!
And yes, they are incredibly smooth and quiet, especially at idle. Even after years of ownership, I'll find myself checking the gauges at a stoplight just to make sure it's still running.
yeah I'm happy it starts and runs! Got to keep it running though... hopefully some helpers come along. Probably get sick of this question 😬
Lots of moisture comes out the exhaust. I went through the whole fuel system first and cleaned it. Maybe it never dried out fully... but that was a couple months ago. I used a bottle of heet to remove any water but I've also read that can actually suck moisture into the system.
Water is a by-product of internal combustion. Vapor is normal ...so long as it goes away eventually. If a car isn't used much it can take quite a while to burn off what has accumulated in the exhaust system.
Or....you could have a leaky head gasket.
The bogging down could be from low fuel... not sure how much is in there, but the rough idle and multiple cranks to start obviously it needs some tinkering. The wires on the ignition coil look crap and some of the injector wires look rough too... the plug wires and cap look fairly new and ok but I'll change them eventually soon. I did rev it hard the other day and got a small backfire upfront somewhere, so I'm wondering if the timing is off a little? Which might explain the difference in the left and right side pulses? This cars intimidating to work on. The engine is huge, gets warm real quick... and mine is smoking and backfiring a bit... ha
as you can see a little bit from the second video... the engine idle seems like the whole engine is a bit shaky. I've always heard something about a smooth **** locomotive like engine. 😬
It does sound and look like a clear-cut misfire. Plugs and/or plug wires, some weak/dead/dirty injectors, problem with the injector harness....as you say.
A backfire in the engine (as opposed to in the exhaust) generally suggests lack of fuel.
Yours looks like it might be a good candidate for 'doing the vee'. Do it all, do it right, do it once....and then forget about it for years. Big job, but doing it alá carte is even worse.
Backfiring.popping back, can also be caused by the voltage to the -ve side of the coil dropping out, crap wiring at play again.
Now its running, stop the "AlaCarte" fixes, and so it once, do it all, repeat in 25 years.
The V12 is SMOOTH, SILENT (unless stood on), and soooooooo reliable, but age, lousy mechanics (experts in some markets), a "I will get to that eventually" attitude, and sadly the car has NO hope.
Start it up at night, open the bonnet, make sure the area is DARK, look for the light display, that is your issue that needs your attention NOW.
Our PreHE was sadder than yours when we got it given to us. Took 3 months of solid work (all before computers and Forums etc) to get it sorted, now it is at 540000kms, and a bloody missile, reliable as any brand out there, and gets driven anywhere in OZ that takes the current owners fancy. Spat an alternator last month, not bad.
Water is a by-product of internal combustion. Vapor is normal ...so long as it goes away eventually. If a car isn't used much it can take quite a while to burn off what has accumulated in the exhaust system.
Or....you could have a leaky head gasket.
It does sound and look like a clear-cut misfire. Plugs and/or plug wires, some weak/dead/dirty injectors, problem with the injector harness....as you say.
A backfire in the engine (as opposed to in the exhaust) generally suggests lack of fuel.
Yours looks like it might be a good candidate for 'doing the vee'. Do it all, do it right, do it once....and then forget about it for years. Big job, but doing it alá carte is even worse.
Cheers
DD
Cool thank you! Yeah I'm planning on doing it all. Getting married in a month so hopefully I can get it going by the middle/end of summer, before it has to be put back in storage. Ugh
Backfiring.popping back, can also be caused by the voltage to the -ve side of the coil dropping out, crap wiring at play again.
Now its running, stop the "AlaCarte" fixes, and so it once, do it all, repeat in 25 years.
The V12 is SMOOTH, SILENT (unless stood on), and soooooooo reliable, but age, lousy mechanics (experts in some markets), a "I will get to that eventually" attitude, and sadly the car has NO hope.
Start it up at night, open the bonnet, make sure the area is DARK, look for the light display, that is your issue that needs your attention NOW.
Our PreHE was sadder than yours when we got it given to us. Took 3 months of solid work (all before computers and Forums etc) to get it sorted, now it is at 540000kms, and a bloody missile, reliable as any brand out there, and gets driven anywhere in OZ that takes the current owners fancy. Spat an alternator last month, not bad.
thank you grant! I know its always hard to say what it might be. I just need to bite the bullet and replace the wiring and plugs or at least a plug cleaning. It was garage kept and stored for 5-10yrs, but it definitely had some rodents living in the engine. They ate the airfilters and there's still a bunch of walnut shells sitting by the distributor. Who knows what they might have gnawed on for fun. For sure need to make sure no arcing is going on or (poof). Is there a good vacuum diagram out there? My 944 idled like a semi till I fixed a major leak. Thank you guys all for the help, so glad I found this forum. The xjs is a beast compared to the 944 and way more technical. Help with the jag is way more needed!
New plugs, cleaning is a waste of time. Gapped to 0.025" and Neversieze on the threads.
Have a read in the XJ Series section, one above this one, and the Queenslander who took Months to do a plug removal on his Carby V12, then keep all that in mind when doing yours.
New plugs, cleaning is a waste of time. Gapped to 0.025" and Neversieze on the threads.
Have a read in the XJ Series section, one above this one, and the Queenslander who took Months to do a plug removal on his Carby V12, then keep all that in mind when doing yours.
ha British lava rocks. Whoops, I meant give it an injector cleaning. Are there any plugs the v12 doesn't like or a recommended one?
I just looked over that plug change in the xj section... I'm pretty sure I would've just rolled it into a lake once threads came off!
I have used NGK BP6EF forever, BUT, in their wisdom NGK has stopped making them, so now I am forced to use BPR6EF.
The fuel hoses in the engine bay will need to be renewed, and I mean ALL of them, and that is MORE important than showing up for your wedding, trust me.
I have rebuilt way too many over the years due to fuel hose engine fires. All the owners knew of the risk, and it was on their to do list, they just failed to inform the car of that list. Each of them paid for a nice trip to Vegas for us both, so I have little sympathy.
You do have some very serious work ahead of you, but the basics are there, and yes, it runs. Forget the smoothness and whatnot for now, that will be sorted when all that stuff is cleaned up and renewed. Then, if its still having a female moment, the seek and find/fix will be soooooo simple.
One wire at a time, and you are finished when you are finished.
I have used NGK BP6EF forever, BUT, in their wisdom NGK has stopped making them, so now I am forced to use BPR6EF.
The fuel hoses in the engine bay will need to be renewed, and I mean ALL of them, and that is MORE important than showing up for your wedding, trust me.
I have rebuilt way too many over the years due to fuel hose engine fires. All the owners knew of the risk, and it was on their to do list, they just failed to inform the car of that list. Each of them paid for a nice trip to Vegas for us both, so I have little sympathy.
You do have some very serious work ahead of you, but the basics are there, and yes, it runs. Forget the smoothness and whatnot for now, that will be sorted when all that stuff is cleaned up and renewed. Then, if its still having a female moment, the seek and find/fix will be soooooo simple.
One wire at a time, and you are finished when you are finished.
oh trust me I know the risks... I can't say I knew the risks beforehand but I read about it real quick. Some of the fuel hoses look like good condition. (Cracked injector boot)
And then others look like they have salt on them.
Im so sick of dealing with fuel and the smell of it. I got blasted in the face doing a filter change on my BMW the other day. Luckily I had goggles on. Strange how some of the wires and hoses seem in decent shape and then others look like absolute hell. I'm just going to do the vee and as long as I don't get blasted with fuel, look forward to it! Thanks for the help grant
Ok last video. Got the instrument panel working today except for the fuel gauge goes straight up and the coolant temp... well that might just not be getting a reading before it wants to shut down. But, this is what's happening. Rev it up and there is definitely a miss happening... making a sputtering noise(like burrrrrrgrgrgrgrr) and then slowly revs lower and lower till it dies... then it doesn't want to restart after a few times of doing this.
Fuel pump.
Plugs and leads etc.
FPR, mainly the LH one are iffy at best.
Wiring.
Running a Lucas V12 with a distinct misfire is NOT recommended, as the Zener diode inside the Amp will look after the spikes, but its only so good.
I know the temptation is so high to run that beast, but with all that wiring mess you have, the risk of other damage is too high, even for me.
That engine will have to run for at least 30 minutes to overheat, and that would be IF the stats are dud, the radiator is clogged, the fan fails to draw air, and so on. There is 25litres of coolant in there.
You do have some very serious work ahead of you, but the basics are there, and yes, it runs. Forget the smoothness and whatnot for now, that will be sorted when all that stuff is cleaned up and renewed. Then, if its still having a female moment, the seek and find/fix will be soooooo simple.
One wire at a time, and you are finished when you are finished.
+1
With these old and neglected V12s you just gotta dig in and get everything 'back to square one' as the saying goes. Lots of work but it's all very "DIY-able".
Running a Lucas V12 with a distinct misfire is NOT recommended, as the Zener diode inside the Amp will look after the spikes, but its only so good.
Grant,
Could you explain what spikes a misfire causes electronically, what job the zener diode is doing and what would happen if it fails to handle said spikes?
When a spark plug fails to "spark" all the energy from the coil must go somewhere. The module inside the amp generally cops the whack, and the Zener dumps that energy to earth.
A plug lead that is not fitted so as contact with the plug top is present, then the same fault, the energy has nowhere to go.
If it fails, the module fries, usually.
Then, running a V12 on 11 or less cylinders can cause bore wash, and lots of other things, especially cars with Cats.
If that misfire is from lack of fuel, as in an Injector being hissy, then the spark plug is still sparking, just got nothing to burn, so the Zener does nothing.
I know of some that have disconnected the Zener, as a trouble shooting step, and that is fine, as long as a spark plug does not decide to stop sparking.
Fuel pump.
Plugs and leads etc.
FPR, mainly the LH one are iffy at best.
Wiring.
Running a Lucas V12 with a distinct misfire is NOT recommended, as the Zener diode inside the Amp will look after the spikes, but its only so good.
I know the temptation is so high to run that beast, but with all that wiring mess you have, the risk of other damage is too high, even for me.
That engine will have to run for at least 30 minutes to overheat, and that would be IF the stats are dud, the radiator is clogged, the fan fails to draw air, and so on. There is 25litres of coolant in there.
My plan is fuel filter, plugs and wires.. prob new distributor and rotor and an injector cleaning. I wish I would've known about the mesh screen in the aux tank before I put the fuel system back together. I actually grabbed a left side fpr off an xjs with 14k miles last week... didn't change anything. Trust me I'm very tempted to run it as is, but I want it to run for more than 30 mins! Ha. Like I said after the wedding, it's getting it all! My hope is of a couple months of driving at the end of summer.
I'm going to take the fuelrail and injectors out today I think and get new hoses on and paint the rail as it's looking a little worn... I noticed looking at pics that my jag seems to have no ferrules and atleast one injector wire already looks like it's been on fire. Ha
are the ferrules necessary?
05-10-2017, 06:24 PM
The old 88' starts and runs a tad rough! vid inside
