Still No Spark 1950 8N 12v conversion.

jinman · Jul 19, 2011

Most likely you have a drain plug on the bottom of your carb. If you can remove that, it will drain the float chamber and may clear any trash or water that could settle there. With the plug out, open the petcock from your fuel tank to allow fuel to drain through the carb. This will ensure that you are getting fuel out all the way to the carb and that the float valve is opening properly. After draining, replace the plug and wait a few seconds for the float chamber to fill up, then retry starting. I would not try to get the engine to start by pouring raw fuel into the spark plug holes. There's too much of a chance that you will fill the cylinder and get hydraulic lock on the engine. I would use starting fluid in the air intake to see if that gets any ignition response.

Soundguy · Jul 19, 2011

yep.. and if you do the start fluid deal.. slip the air tube off the carb to keep the start fluid from getting filterd by the oil.

soundguy

JC-jetro · Jul 19, 2011

Soundguy said:
not an apples to apples comparison.. but did make me think about it.. a ford powerstroke diesel has a cps sensor that will up and quit and leave you on the roadside..... the cps ( cam sensor ) on a ford diesel is easy to change.. cut the wheel hard tot he side and a lil tab with 1-2 bolts hold it in.. unplug and plug new one it. like a 20$ part.. yet.. it will elave you walking on the roadside.. most powerstroke owners I know carry one in their glove box just for this reason..

soundguy

Sorry for going off tangent again

but mine was on the bell housing at 11:00 o'clock sensing the crankshaft as you face the front from the driver side between the engine and fire wall. All I could do from top was to barely shine a light on it. I would not bore you with all the hoops I jumped thru just to get a socket on it, remove and install the new... just thinking about it brings cold sweat. My CPS was right under $70.

JC,

J_J · Jul 20, 2011

2LateIWon,

I am not so sure that you have verified that you has a good spark to the plug at the right time. You qre getting spark at some time, but when.

As far as the carb, let enough fuel in the bowl to fill it, then shut off the fuel, then try to start.

Maybe you have voltage to start, but none when in the run position. Check resistor.

Is that a 6 v coil or 12 v coil?

What is your battery voltage when starting?

If you are back firing, I would think the valves are sticking or timing is off.

You should also know that the point gap will change the timing.

Increasing the gap will cause the timing to be delayed . Set point gap before timing.

Set the plug gap, set the point gap, set the timing. Do not assume the plugs come set correctly.

With the right fuel mixture and the above items set, it should fire and keep running.

Let us know the results.

2LateIWon · Jul 20, 2011

Sorry last night was crazy at the 2Late's house hold so I didn't even get a chance to go out and do anything. To nights church but (depending on how tired I am) after church I'll try to check it out. If not my wife and kids will be gone (church camp) Thursday and I will have no excuse after that LOL Plus I'm going to see if I can con a friend of mine over to see if we can make something happen.

Soundguy · Jul 20, 2011

no start / run on that 8n ignition.

it's a key on / off for ignition, and a seperate thumb sized starter button on the trans cover that is neutral safety locked.

soundguy

jinman · Jul 21, 2011

In addition to what Soundguy said about the ignition/starter switch. I would say it is highly unlikely that you've changed the timimg unless the dist looks like it has moved in the clamp. If that clamp is tight on the base of the dist, then it would take a major mechanical failure to change timing enough to cause your problems. You can always run #1 piston up to the top of the cylinder on the compression stroke and then check the dist by looking at the rotor button to see if it is pointing to the #1 wire. in the cap. If it is close, my guess is that your timing has not changed. I believe it was mentioned before that this is also how you tell which wire should be #1 if you get them mixed up on the cap.

J_J · Jul 21, 2011

Looking back over the post, he never did say when the tractor last ran, and if it was running right then. Like Jinman said, turn the engine to #1 cyl at TDC, if that is the timing, and see if it will spark. If it does, that implies that the timing is correct or close and that the failure to run is probably a fuel problem.

One source quoted this.

Static timing is 4-BTDC on non-running engine.

2LateIWon · Jul 21, 2011

I bought this tractor a little over a year ago and have used the crap out of it. Just out of regular maint. I did a complete tune up except for the points and condenser. I've had other issues but never this or anything related. Just hydraulics, flat tires, lights. etc.etc. before this I had #4 spark plug wire short and start missing. So I replaced all the wires. I was brush hogging 40acres (this was about a month ago) was my last job with this. It mowed flawlessly with no problems. I was able to cut about 25 acres came back the next weekend and cut about 10 more acres then is started running rough. And just got worse from there under load. No load it would just miss a little. So I thought since I never changed the points and condenser out I should. So after that I changed them out is when I had all my problems. Before this it never had a problem firing up even in the dead of winter and not being started up for a few weeks. I could go out there and turn the key on pull 1/2 choke and she'd fire right up. That's why I'm so dumbfounded about why it's not running even after WE found out why it had no spark.

Soundguy · Jul 21, 2011

4'btdc at 400 rpm, and 18' max advance at 2000 rpm 27-31 dwell

soundguy

here's a page out of the ford pocket reference.. top line on the chart is the N