Jaguar is not the only one that numbers from the flywheel end.
Tom
Who else? I was wondering that when I was looking for why Jaguar did it.
Peugeot…
…plus 20
Tom
On a Jag engine, you can check timing from 1 or 6, although I’m sure that someone has some pedantic nonsense as to why this is bad. If you want to call it one, go right ahead. I think back to front is a European thing. MG, Triumph, Porsche, all of them. Maybe timing no 1 from the back was thought to compensate for camshaft twist. Not that there will be much twist at idle. Or maybe it’s just tradition. Aside from our quaint convention of counting front to back, it makes no nevermind which end you start from.
Good news! It was your Edit at the end of your post that provided the solution. I replaced my newly purchased distributor with my 55 year old original distributor (with new points and condenser). The car ran for about 20 seconds on its own and then stopped without any bangs. I then discovered that the front carb was flooding.
Thank you and all the others for helping me with this saga. I will investigate the carb problem and may get back to Jag-Lovers for further help.
Peter
1 Like
what kind of distributor was the new one?
Liam,
It was a refurbished Lucas 25D, which looked good and was the Jaguar upgrade from the original Lucas 22D in my car. The problem was it had a poor (non standard?) points plate, which I intend to replace in the future.
Peter
Hi Erica,
Well. I guess I’m not ‘out of the woods’ yet!
The car tries to start with starting fluid, but never catches after I release the starter. Some plugs are firing but the engine shakes, indicating to me that some plugs are firing. All compression still at 175psi. The plugs do not give me any clues.
Any thoughts?>
Peter
I’ve had a a squiz through the posts but has the plug lead sequence been verified as correct?
Hello Peter - 1) as Robin mentioned, verify that the plug wires are in the correct firing order sequence; 2) not sure about this suggestion for the E-Type, but your description of the problem almost sounds like you may have lost the electric path, from the ignition switch position for “run”, but still have it there for the “start” position - this could be the reason the engine is not continuing to run after you release the ignition from the “start” position - Tex Terry, II - 1991 XJS V12 Classic Coupe, 1986 XJS V12 Coupe - sent 10/9/2020 2312hrs. EDT USA.
Peter,
Did you verify that the wires are connected , from the distributor to each plug, as shown in the photo below ?
Marco
Hi Marco,
Thank you for your suggestions.
Yes exactly, I have the same page and the details above the Fig 19 diagram. I’ve checked the wires again and they are in the right order and position on the distributor.
I’ve set the ignition timing to 10 degrees before TDC as explained in the manual and used the vacuum advance vernier to fine tune the spark. I’ve also used a spark detector to determine that the spark is getting to each plug.
My next action is to remove the positive wire from the fuel pump, to eliminate any action from the carbs, and then try to start the car just with starting fluid or gasoline from a spray, having first set the throttles on each of the carburetors open the same amounts (2 turns on the adjustment screws with the choke in the middle position (‘cold’ in my car)
What I’m looking for is a short smooth engine firing without shaking.
Peter Dundas
I’ll let you know what happens!
Thank you.
Looking forward to knowing what is the issue .
Good luck !
Marco
Peter, Let me bold.
You say that you have the wires in correct sequence and see a spark from each of the six. I believe you. I know this all started with a carb rebuild and a replacement distributor.
Your carbs are getting fuel, I think you have said.
In my experience, with my car only, the XK engine is incredibly forgiving of minor timing errors if simply getting the engine to start is the goal.
The car is not refusing to start because you are a couple of degrees out. It is refusing to start because you are 180 degrees out. A spark when #6 (or #1) is at TDC or 10degrees BTDC is no use if it is at the end of the exhaust stroke.
I’ve been wrong before, but I really think you need to check this possibility. The thread suggests how.
Liam,
Thank you for your email.
Several people have suggested the same 180 degree ‘out of phase’ problem.
However, I have timed the engine, in the recommended manner, by turning the engine to ‘10 degrees before’ mark on the Harmonic Balancer and then making sure that the left hand cam shaft is in the correct position (removing the oil cap from the LH Cam cover and examining that the lobe of #6 is pointing outward and that the notch in the front of the cam is at the top. This process needs a small mirror and a flash light to see.) As you might know, the notch is used when valve timing the engine during rebuild, using the standard Jaguar valve timing gauge, without the cam cover in place.
When this is done, the distributor rotor should be pointing to the 4 o’clock position.
If this was 180 degrees wrong, the distributor rotor would be pointing to 10 o’clock.
As I said before, the compression is 175psi on all cylinders and the distributor has new points.
Just a little history. I’m the original owner of this car, purchased in Boston 1966, driven every day, accumulating about 82,000 miles until 1977, when part of the floor and associated undercarriage had suffered from the New England weather, and had to be fixed. The car was then garaged for major restoration. I rebuilt the engine and repaired the body work, with a friend who knew how to seam weld the complete set of floor panels and outer sills. In 1985, the car was ready for the road and displayed at its new home in Pittsford NY.
Only driven 8800 miles driven since 1985, professionally repainted in 2008, averaging 300 miles per year since then. In 2019, had a ‘cold starting’ problem; found leaking carb float and decided to rebuild all 3 carbs as a winter project.
Peter
Peter,
I see you live in Pittsford NY.
Did you by any chance work at Xerox?
Bill Wayman
Are the throttle spindle clamps all hooked up together.?
Maybe only one carb is operating due to a loose spindle clamp.
I spent the afternoon helping Peter on this problem.
Should be simple… fuel, spark and air is all we need…
First I checked his carbs, fuel level was correct in all 3 jets.
Jets were centered.
Choke lowered jets as expected.
Fuel smelled old, so we bled some fresh fuel from the tank out the fuel filter and then sucked on all 3 jets to empty the float bowls. The fuel pump then refilled float bowls while we watched. Butterflies opened with gas pedal and were synchronized. FUEL OK
At this point we tried to start the engine, It took a lot of cranking (with choke) and finally ran at a very slow idle for 30 seconds. The funny thing was that the throttle made no difference!!! It just barely slow idled. I was able to jump out and feel the exhaust pulses, they were robust puffs. I conclude the exhaust system is not plugged.
Engine stalled.
I immediately felt the exhaust manifold and there was warmth on every cylinder outlet.
It’s firing on all cylinders.
WTF!
We then checked both exhaust and intake camshaft timing and they are both correct.
So… he did leave the intakes uncovered over the last winter and did note mouse droppings on the engine.
It’s possible his intake manifolds are clogged with mouse nests. But I find it hard to believe they would all be clogged the same. When it did run it was uniform in pulses just that the throttle made no difference! It’s starved for air flow. Could be clogged intake or plugged exhaust system. I suspect intake.
I suggested he buy a bore scope and have a look inside his manifold and intake valves.
Thoughts from the brain trust?
I repeat my comment of two days ago. A massively mistimed engine (ignition) will be hard to start, will not respond to throttle and will be putting unburned fuel into the exhaust manifold where it will continue to burn providing heat. Yes, I could be wrong, but apparently no one is actually right yet. 
Here’s a thought. Many years ago, I had a similar problem with my MK2. I rebuilt the carburettors and the car ran poorly. It sputtered with a push of the pedal and barely ran. Fuel starvation is what came to mind.
I pulled the carb dashpots apart and noticed that I had assembled one of them with the piston return spring upside down. Note that the parts manual shows the spring to be of uniform diameter, put the actual spring has one end narrower than the other. That was many years ago and my memory is foggy on which way the spring goes, but I turned one around to match the other (MK2 has two S.U.s) and that solved the problem.
Give it a whirl…