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Confused with starting/ignition/timing

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Please email to me as well, see address below.
 
What a great site! I'm going to go through it and check each of the different areas that are described. Unfortunately, my wife invited people over for the game, so it will have to wait until tonight.

I do have a full tank and I believe I recall the tach jumping- I'll look again tonight.

I know it has to be something really dumb that I've forgotten, or I'm starting to lean to the condensor (although it was working good before) By any chance would the condensor be sensitive to a magnetic field? While installing I used a magnet to hold the screw in place while I put it in. It's a bolt finder type, so I suppose it's fairly strong.

One thing for sure is I'm learning a lot, and that's why I try this stuff myself. I really thank you guys for the help and the patience with my slow schedule and progress.

If it wasn't for your support, I would have given up a long time ago! /bcforum/images/%%GRAEMLIN_URL%%/smile.gif
 
The only reason I asked about the gas was a few years ago I spent the weekend doing a bang up job of tuning the Sprite, got done and took the wife for a spin. 4 miles out and the car dies, popping, banging and will not fire. I jumped under the bonnet, fiddled with every thing, throwing my beautiful tune-up out the window. While having my wife crank the starter, she glanced at the fuel guage and started to laugh....say-no-more!!
 
I've actually done pretty much the same thing but it involved a newer vehicle and 3 days at the dealer before they called me and told me it was out of gas lol... They were trying to drain the tank so they could take it out and change the fuel pump...Bad sending unit. Anyway, the condenser should not be sensitive to a magnetic field. These engines will run badly with surprising ease. It's getting them to run smoothly that can give us fits at time. What I'm saying is, while I doubt it would actually run at 180 degrees out, it will run (terribly) if you get the firing order mixed up. I am still suspect of the condenser in some way. Make sure the wiring isn't grounding out against the dizzy body (both points and condenser) Inspect the wiring carefully for bare spots or evidence of grounding out. I've fought a skinned condenser wire before. While I don't think this is your problem (since you've tried two condensers) the issue could be this simple.
Keep us posted,
JC
 
One more thing to absolutely check that the condenser wire is correctly placed with respect to the insulator on the long end of the points spring. It should not be grounded at that point, and it's all too easy to install it with the lead grounded, I know, I have done it way too many times.

See attached picture - I mocked it up on an old 948 distributor I have lying around, so it's rusty and the screws are missing, but I couldn't find the right screws, and the wiring is correct - both the wire from the condenser and the wire from the "terminal and lead" should be installed under the top part of the insulator, and connected to each other but NOT connected to the top nut.
 

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I had this happen to my second TR6 once. My problem was the high tension lead that runs from the distributor connector to the points was broken inside the conductor sleeve. You cannot visually see the break but it was bad and had be renewed. This wire when aged or pulled has very fine strands of wire that rot out or break.

I have also witnessed that when the points insulator (white plastic insulator) allowed the condensor and high tension lead to touch the post and cause a direct ground which will also cause a bad mis-fire.
/bcforum/images/%%GRAEMLIN_URL%%/smile.gif

1972 TR6 in Restoration
1959 TR3A Restored 2001
 
Bailee, that's the low tension lead, and they are very prone to failure. I used to deal with a local parts house that practically wouldn't sell a set of points without selling a low tension lead with them.
Jeff
 
What type of A Weber carb do you have? Downdraft? Did you install it? I ask because tis sound exactly like what we went through on our 77 midget. We converted to a new downdraft weber carb and got exactly like what you are talking about. Backfires, flame through the carb. We replaced the coil, ignition, distributor retimed it about a hundred times and all before we realized the problem was that it was sucking too much air through the intake manifold. Turns out the intake manifold was hitting on the exaust manifold and although it seemed to set and tightened down, it was sucking air at the bottom. We had to grind off the exhaust manifold in the two spots and then replace the intake manifold gasket and reattach it. It fired right up and all we had to do was reset it like it was supposed to be originally.
 
The reason why it is flimsy is that it goes from the shell of the distributor (which is stationary) to the part which moves to advance/retard the spark, so it must not impede that movement in any way or other problems occur.
 
After several days of thinking hard about this while I had to go to my "other" job, I got back to work on the car and tried a few things. After a while I had success! It started on the first turn of the crank! But now I'm still confused.

I thought the culprit was the plastic washer between the condensor and the retaining nut on the points. The picture ncbugeye had really helped and I noticed that the P.O. did not have the plastic washer there at all, but had a steel one. After putting it back to gether it didn't start.

I then forced the screw off the points and repaired it with JB Weld, and then put in new points, condensor, and cap. Again no luck.

O.K., so now is where I'm confused and you are probably going to laugh at how stupid I am, but I'm tough, so here I go. I was moving the wires around on the cap, and tried #1 in the 7 o'clock hole. It would crank easy for one turn, then stop abruptly. I then kept rotaing the wires around the cap (which I have done 2 times in the last 4 days) and lo and behold it fired up when the #1 plug was in the 4 o'clock hole. O.K., stop laughing and please tell me how this is possible and what I missed. I static timed at TDC and the rotor pointed to the 1 o'clock hole like it should. My dizzy is fitted with the vacuum assembly tilting slightly forward, like I've seen before. I had an MG in the past and #1 was in the 1 o'clock position just like I was used to. So I don't know.

So there you go. I have exposed myself to the forum for the generations to come. So tell me, am I crazy and doomed to a lifetime of chuckles when someone falls on this thread during a search, or am I on to something strange?


Please be kind...I now reluctantly hit submit...... /bcforum/images/%%GRAEMLIN_URL%%/frown.gif
 
So you're a victim of another DPO. No big thing. The dizzy drive dog is shoved into the cam in some "odd" position. That you've found a point where it starts/runs is to your credit!

To go thru the drill of setting it up as per the "book" may well be a waste of time if you have it running now. You can accurately time the electrical trigger point statically with a total disregard for where #1 is located on the cap, if the drive dog gear is mislocated on the cam. Hard to wrap your mind around the idea that the dizzy #1 position and the engine 's #1 TDC are that "variable" but it's true. A Bentley manual and some study will show how this all inter-relates.

Just glad it runs for ya!
 
So I'm not crazy! Is there any damage that can be done being in this odd position, or should I just leave it and make 4 o'clock my new # 1?
 
So there it is! Thanks to everyone, I learned a ton, which is why I come here.

Another successful end to a long thread! /bcforum/images/%%GRAEMLIN_URL%%/smile.gif
 
I'm lookin' at "age and stage" here: If he's got it running now and fiddles with it enuff to gain understanding of how it actually works, then at some point he'll be able to set up the dizzy shaft/cam "by the book" and get it right with his eyes closed.

Understanding that the diz drive can be in about any position and still be made to run the sparky bits correctly is a great thing, in my estimation. The "convention" for setting the thing up according to the book is not necessarily a lesson in the understanding of the mechanical & electrical bits as a "system". Whereas what 10M is doing IS.
 
"with understanding comes enlightenment"

Yoda
 
Wow! After reading this thread I'm impressed by the people contributing and asking questions.

It's good to see that all questions are treated with respect. Other BBs sometimes generate replies like 'go read the book'. The detailed answers show a great deal of concern for fellow LBC owners and their problems.

Glad I found this site. As I'm in the process of rebuilding a 1275 engine (fast Street) I'm sure I'll be tapping this great source of knowledge.
 
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