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no spark to plugs!!!

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AnkwizTR3a

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I am getting no spark to plugs, i replaced coil, points/condenser, plugs. engine is spinning appropriately, I have tried many configurations - pos ground, neg ground - polarizing generator at generator, check most wires - I am at a lost - does anyone have any detailed information (may pics) on correct wiring setup. Thanks
 
Are you running conventional points? If so are you sure they were assembled in the right order? It's very easy to put them back incorrectly which creates a short and this no fire.

Once you confirm you have power to the coil this would be my next thing to check.

Let us know how you get on with this.
 
I agree, the fact that you say you changed the points would remind almost anyone of some time when they stacked that insulating post in the wrong order and were baffled by no spark.

points.JPG


Hard to see in a photo but the black wire, orange wire and the points themselves are insulated from the body of the distributor by that 2-piece insulator that goes below & above (and right thru the middle of) them.

It may be a one piece thing with 2 halves joined by a little strap (that's how the one in the pic is) or it may be 2 separate pieces.

Yes, it could be lots of other stuff -- but this is the first thing I'd check.
 
Personally, I'd check the rotor first. I can't count how many times I've left it laying on the fender!

Then check the points. Just to restate the obvious, after the spring goes on the post, both wires must go on next, the plastic piece goes AFTER the wires. Then a small flat washer and the nut.

If all that looks right, my next step would be to connect a test lamp to a good ground and the wire between the coil & dizzy. Turn the engine until the points are open, turn the ignition on, the test light should come on. Turn the engine until the points close, the light should go off.
 
TR3driver said:
Personally, I'd check the rotor first. I can't count how many times I've left it laying on the fender!
Click to expand...

that was my first thought because he didn't mention the rotor in his initial post...
 
We all have - more than once! :blush:
 
Yep, I've done it too. But I'm going to put money on the internal hookup insulator thing because that one still might bite you even after you put back the missing rotor!
 
As you sort through this... remember that in your first post you said you had tried different "grounds". Before you go any further in looking for the spark, make sure you have chosen your final ground configuration, hooked the battery up accordingly, and re-polarized the generator. The last thing you want to do is forget to get all the charging system configured properly, finally get the engine going, only to see white smoke coming out of the control box or generator.

Consider this another vote for the insulator washers on the points.
 
Also the low tension coil to dist lead wire has been known,because of age, to break inside the cloth cover where you cant see it and cause problems but I also vote for the insulator thing as the culprit.
 
Spent my first two weeks getting my 3A going with the no spark and the points connected wrong!
 
I has a problem on my TR6, turned out to be the distributor cap... might want to replace the cap and rotor too

Hondo
 
First, find out if you have spark out of the coil.
Spark to the plugs is immaterial at this point.
If you can't get the wire out of the cap easily, find an old plug wire, remove the high tension lead from the coil, insert the old wire, and hold the end 1/4" from the head while someone cranks it.....with the ignition on.

If you get spark out of the coil, then we know where to look.

You area of problems is too broad.
Let's narrow it down.
 
Thank you everyone for responding - it surely helped alot!!! I now have SPARK, I believe it was a short in the condenser as well as the points. I am able to turn car over and it runs. However, I can only keep it running for about 10 seconds, I'm assuming all I need to do at this point is fine tune everything - is there any pointers anyone can give to guide me in the right direction on proper tuning steps. It doesn't seem like it is firing at all cylinders - very rough. Thannks in advance.
 
check to see if you get spark at each plug, change plugs and likely some fuel issues you need to work through.
 
Did you change the timing at all? Plugs all on the right wires?

But, typically running and then cutting out in that short amount of time is typically fuel not spark related.

That said, make sure the plugs leads are on the right plugs before moving on to fuel.
 
I am getting my 1958 TR3A ready for a nice summer of TR driving after it was stored since October. I had all the same trouble as you keeping it running longer than 10 seconds. So I drained out about 2 gallons of old gas left in my tank all winter (I have a convenient drain valve where the drain plug is normally located) and I bought and poured about 2 gallons of new gas into the tank. I mopped out the float bowls and poured in new gas there to get it started. Now it runs great.

I'm convinced that old gas - more-so now that they are adding ethanol - causes a lot of problems we never got before.
 
Don Elliott said:
I'm convinced that old gas - more-so now that they are adding ethanol - causes a lot of problems we never got before.
Click to expand...
:iagree:

But I thought you were going out of your way to find non-oxygenated fuel? (In Canada)
 
AnkwizTR3a said:
Thank you everyone for responding - it surely helped alot!!! I now have SPARK, I believe it was a short in the condenser as well as the points. I am able to turn car over and it runs. However, I can only keep it running for about 10 seconds, I'm assuming all I need to do at this point is fine tune everything - is there any pointers anyone can give to guide me in the right direction on proper tuning steps. It doesn't seem like it is firing at all cylinders - very rough. Thannks in advance.
Click to expand...
As others have said, I'd be looking at mixture next. With the engine cold, it will need both extra fuel and extra air to stay running, both of which are normally provided by the choke. So look at whether the choke is affecting both carbs equally. One way forward is to disconnect the choke return spring, and see if you can get it to smooth out by pulling the jets down a little lower (which richens the mixture) by hand.

You need to get it running on all 4 before doing any 'tuning' as such.

Of course, there could still be electrical problems, like a bad plug or plug wire. I think my TR3 is developing a carbon track in the dizzy cap, as it sometimes only wants to run on three cylinders. But I would look at fuel first. I'll also be checking fuel delivery to the rear carb, etc.
 
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