No Spark to plugs...please read and help

[nj82tj]

back to no spark now?

and now she won't turn over?

sounds a whole lot like a bad battery.. bad connection.. poor ground.. or bad starter bushing making for an excessive draw.

The spark is the same if I connect it right to the coil, I mean a weak small spark from the dist cap. The battery had a full charge. I had if charging over night. Tell me about the bushing on the starter. Oh and it does turn over like crazy. Just won't start.

 

[Soundguy]

if it turns over good.. bushing is fine.

ok.. to recap.

spark from a wire in the coil to block is good.

spark from dizzy cap to plug is bad.

new caps.. new rotors.. new condensor, timing looks good..

that's a whole lot of 'don't mix' stuff.. hmm.

i'd get rotor pointing at #1.. put cap on.. put #1 wire on a plug and ground to block with jump cables.

now turn on key.. and now continously short out the wire at the side of the dizzy using a wire and insulated tool.. should get snappy sparks...

if you do with it 'manually' timed... but not when cranking.. then I'm back to thinking some sort of stuck advance or timing issue.

if no spark/bad spark with this test.. then it's darn odd...

post back..

 

[EE_Bota]

I have yet to pull the distributor and look at any of thoes internals. I just picked up a new cap and dust cover to be sure. It did not start. The dust cover has the fiber washer on it. I tried to direct wire a second battery right to the coil, no different. Um, what else...points are gapped, I did check timing by pulling the plugs and using the thumb over hole method. Every wire seems to match nicely with the rotor. I did loosen the distributor and turn it about a 1/8" at a time just to try and get it to hit. No luck, it's now back in its original location. I replaced the condenser again while I was in there. No luck. I do however notice a weak spark at the plug (when grounded on the tractor just for inspection) when the starter is almost done cranking. I hadnt noticed that before. Still won't turn over though. I'm getting close to pushing her into the street and letting my neighbors pond take care it it...it's so frustrating because it makes no sense! Thank you again everyone for all your input thus far. If anyone else is bugged enough by this, feel free to message me and I'll give you my phone number so we can talk directly. I'm about out of options here.

**the weak spark I'm referring to is via the dist. cap**

I hope this makes sense...I was tired and distracted and in a hurry.

Maybe look at this video

How Car Ignition Systems Work Video

then ask a question so we will know what is it you need to know that you don't know. You are at the point where you have everything up in the air, and you trust nothing; that's bad. You must find things to be known good, and therefore eliminate them. For all we know, this is all over fouled plugs.

You should be able to make the coil spark anytime you want without even turning the engine over. Many systems, the points supply and then breaks the ground to the coil. You should be able to remove the little wire going from the distributor to the coil, and use a piece of wire directly from that coil terminal to ground...each time you touch the wire to ground, the coil will charge up, and each time you remove the wire from ground, the coil will spark. Just being able to spark any time you want is a help. I could use the method I just described to check that the coil works.


While you have the little wire off the coil, you can hook one lead of your meter to the wire, and the other to ground, and slowly rotate the engine by hand (plugs all out to make it easier) and you can "see" the points close by noticing the resistance reading on the meter go to nearly nothing...the lower the better. I haven't done it in years, but I would expect something less than 1 ohm above your meter's lead resistance.

You can see the points open again by seeing the resistance go to a very high number (should be the same value as when your leads are hanging in space touching nothing.) There is NOTHING about that system that should be a mystery to you with only a little study here, and on the internet.

You could cut the side out of the old distributor cap like I suggested and see the rotor lining up with the posts. Alternatively, you can make marks all around the cap that match where the posts are, and then transfer those marks to the distributor body. But with the cut out cap approach, you can actually see where the spark is going.

You can put a long nylon tie wrap in the spark plug hole and check cylinder position instead of using your thumb trick. Your thumb is great for telling if you are in the compression stroke, but the LONG nylon tie strap is great for knowing when the piston is at top dead center. You should spark near TDC. A spark gets created just as the points OPEN. Therefore, it is easy as pie to use a meter and a tie strap to get the spark timing pretty close.

What we expect to happen: when a certain cylinder is very near top dead center on compression stroke (as witnessed by your thumb trick and the nylon tie wrap trick) the points are just on the verge of opening and the rotor button is pointing directly at the post for that cylinder's wire.

Check the rotor...it should make sense. Can you rotate the rotor by hand? You should not be able to except a little bit, in one direction, and against spring tension, the spring tension coming from the centrifugal advance. If you rotate it a little, and then let go, it should snap back due to the springs.

Understand that if the rotor is not pointing directly at the post, but is past, that will get worse at speed due to advance. Most rotor buttons have a wide tip, and usually it is possible to have the rotor point its electrode at the cylinder's post with no change in gap whether advanced or not.

You can use your meter to check the resistance of a spark plug...one lead to the top tip, the other to the curved electrode...if it reads infinite it MAY be good, but if it reads anything else, it is bad (fowled.)

I hope this helps. If the tractor were here, I'd be all over it with my meter. If you have a meter, and you relax and think it all through, you will surely find the problem. But to progress, you must find some things GOOD, and keep working until all things are found to be "good."

Oh...one trick I used to do frequently...I used to head out with a flashlight and get sorted, and then try it in pitch darkness. I've seen engines flash like a Christmas tree in the dark.

 

[nj82tj]

I believe I may be onto something here...my neighbor came over and we bounced ideas off of each other, long story short we pulled out the distributor. Low and behold, who ever owned the tractor previously though it would be a good idea to hold the timing gear (I think that's what it's called) on the distributor shaft with a...screw. I now believe that when I throttled it up and down I snapped the head off the screw and the gear slipped, by about 1/8" resulting in my non firing. I ran out of garage time tonight since I work at 7:30am so I still haven't cranked it over but I'm crossing my fingers and hoping that tomorrow will be the day. I'm going to bring up cylinder 1 to top center and align the distributor so hopefully that will do it! I attached a pic of the culprit below...I'm not a serious mechanic by any stretch, but I sure as **** wouldn't use a screw in place of a roll pin...it has since been replaced with the correct roll pin.

Look at this beauty...


Hopefully this will do the trick.

 

[TraderMark]

I've been watching this thread closely and I have my fingers crossed for you!

Mark

 

[Soundguy]

good find. I've been back and forth thinking timing, and back in post 58 i started wondering about that pinned gear.. glad you pulled it and found it, as it REALLY sounded like you were getting good fire befor eht edizzy, but thru it no.. and that , once you repalce all the parts inside.. can usually only mean the rotor and tower aren't lined up good..

post back what ya find.

soundguy

 

[Ford851]

Can't wait to find out if this solves the problem. What al learning experience this has been.

 

[Soundguy]

it was really sounding like a non sync issue

 

[nj82tj]

I tried to fire her up tonight and it almost took I just have to get the timing fixed correctly I believe. Hopefully by tomorrow it should (knock on wood) be running...I'll be sure to repost when I get her out of the garage under her own power.

 

[Soundguy]

keep us posted!