F20 Starting troubles

Hello Guys,

I have been restoring my F20 that ran perfectly before I started the restore. I have not done anything to the motor at all. I have put a new coil in and a new condensor. I have new plugs and plug wires on it. I have a rebuilt carb that I bought about a year ago on it.

When I tryed to start it yesterday it would not start. I thought that maybe because it was sitting for a couple months not running that it was just being stubern. We belted it to another tractor and all I could get it to do is pop and backfire out the exhaust. A couple times it shot flame out of it. So today I worked on it somemore in between getting the other tractors out to the show. I changed the coil and the condensor and one side of the points(the other side was not the right one in the kit)but I did clean it so it was nice and shiney again. I then tryed to start it first by cranking and no go. So then we hooked the tow strap on it and tryed to pull it and still no go even after about a mile. It is dumping gas out of the bottom plug in carb after being cranked on or pulled for awhile. I opened the drain cock on the side of the carba nd am getting good fuel out of there. I have checked and cleaned the valves and none of them are sticky. I checked spark yesterday and had spark. I did not today because it started to storm and i went from the shop to the house. I will do that tomorrow. The inside of the exhaust manifold is wet and smells like fuel but for some reason it dose not want to fire and run. I have made sure that the primer cups are tight so they dont leak off compression. I am just stuck. I have a manual and a IT manual but I cant figure it out. Could it be that the magnet is on wrong on the mag? I have the IH out but could someone repolarized it backwords? Could it be something stuck in the carb? Something varnished from sitting to long? It is a new chinese manifold could it be something wrong with that? Could it be the mag is weak? It ran right before we took it apart perfectly. That is why I am confused. Thanks Guys for the help! It was IH year at the show this year but doesnt look like the old girl will make it there this year but we will spoil the day for those green ones next year when we get her out there. Thanks Guys!

Jason

All the fuel leaking out and the wet manifold say no spark. First are your new plug wires copper cored, they won't run on modern suppression wires. Second I would redo the full timing procedure. they don't have to be off very far to not run at all. I could post the procedure if you need it.

Sounds like your timing is off. Get #1 cylinder on TDC for the compression stroke. Take #1 plug out, and crank over with your thumb over the plug hole. when you feel it pressure up, you are on the compression stroke. Use a wire in the plug hole to determine when you are on TDC.

Now, take the cap off the mag. Is it pointed at #1 plug? Did the mag impulse just trip when you got to TDC? if the answer to these is NO, then your timing is off and will produce the symptoms you are describing.

Make sure that you have the spart plug wires in the correct order and going in the correct direction. If you have the the right order but in the wrong direction, two cyclinders will fire at the right time and the other two will fire on the exhast stroke. This may be what is happening to your tractor.

Yes, I did learn this from experience!

flooded, ?, wet plugs do not like to fire. pull the plugs and dry them, a small propane torch helps or blow dry with air hose. i have also done this by spraying with starting fluid and burning it off ( outside, don't need a fire) spin engine over several times with plugs out to purge cylinders with air, add a small amount of oil to cylinders and turn engine over to lube rings, this helps compression. install plugs and start it, don't over choke. hope these thoughts help you find an answer. ,leroy

Check the firing order of your plug wires on the cap. Hold your hand over the throat of the carburetor while someone hand cranks the engine to see how much suction you have. You need good manifold vacuum to pull the fuel into the engine. Hal

It sounds like the timing is off or pug wires on wrong. You can also take one of the inspection covers off of the block and tell when you are at TDC. Autolite 3077 are great plugs for not fouling. Not trying to start the great plug debate, but they work great for me.