504 stops running

JUST GHANGED POINTS PLUGS COIL ON MY 504 IH TRACTOR.STARTED IT UP AND IT RAN 5 MINUTES AND DIED TRIED TOSTART BACK UP AND POPPED RIGHT ON.AGAIN IT RAN FOR 5 MIN. GETTING GAS NO PROBLEM. GOT ME BAFFLED. ANY HELP. JIM

Try starting it with the gas cap off

Sounds like the vent in the gas cap is plugged

I would reinstall the old points to see if it will stay running. You may have a defective set of points. Hal

CANT PUT OLD POINTS BACK IN THEY WERE NO GOOD, IS THE COIL SUPPOSED TO GET HOT TO TOUCH.STILL DOES IT GAS CAP OFF.

coil should not get HOT, when it shuts off on you take the lead from the coil that runs to the dist and see if it sparks against the engine block. if it sparks it means its still outputting voltage to the dist to make spark. if it doesnt you have a bad coil.

IF COIL WIRES GOT CROSSED WOULD THAT DO IT OR NOT.

If you had the coil off, the distributor wire goes to the - post on the coil. Might be a bad condenser, you can try the old one.

Quick as soon as it stops take the drain plug out of the carb to see gas flow. You need to find out if its gas or spark. If it runs for 5min sound more like spark although it could be the gas tank vent is not doing its job. Just for a quick fix loosen up the gas cap mite want to tape it so it doesent fall off but see if the engine stops after 5min again and that would tell you quick the cap vent is not working. You dont need to change parts do some quick easy things first. Yours wouldnt be the first one to have a bad gas cap.

My first guess is ignition compoents, but could be the carb is getting starved.

Burning off the gas faster than it's coming in.

Of course, makes sure when you open the gas shutoff valve you do it all the way.

Make sure the gas line is clean and free from any obstructions, gas should flow through very strong.

After that I'd try changing ignition components if appropriate. Sounds like you changed the coil, but you might consider the condensor. Change or clean the points while your'e in there.

After that.... sounds like something that's changing once the engine heats up...

Valves maybe? Make sure the valve lash is set properly so they can expand properly.

I'm assuming you've checked your coolant, and you're not overheating...

Once you've covered all the basics, I'd start thinking about the carb again, maybe remove it and clean it all out.

A hot coil is a bad coil. They can be hot from engine heat and running behind the radiator, but they should never be hotter than the housing of the distributor where it mounts. The polarity of the coil matches the polarity of the battery. If negative ground, the coil negative is hooked to the distributor. Hooking it wrong will not hurt it or cause heat, it might not run as well for a variety of spark at the plug reasons, but no damage. Jim

Let me back track a little. The symptoms are dead on for fuel starvation but you just did some work on the tractor.

Did you change the points, plugs and wires because of this problem or did the problem come after?

The 504 is very simple a plain old carb and point ignition system. Fuel air fire and your running.

For fuel starvation: Make sure the gas tank cap vent is working then blow out the fuel lines then rebuild the carb.

For Air: unhook the air cleaner to see if that's the issue

For Ignition: I like to first use a spark tester that goes between the spark plug and spark plug wire in one of the cylinders - very common for lawnmower engins. As long as the ignition switch is on and the engine cranking you should see a flashing light.

Points are the most common problem followed by plugs, wires coil and condensor.

It's all about eliminating the items that are working.


I'm assuming that the tractor is running fine on all cylinders for the 5 minutes - exaust is normal.

Still think it's fuel - you could pull of the air cleaner tube and have a cap of gas handy to toss into the carb as the enging dies. if the RPM's pick up its definatly a fuel problem.

Blow out the lines with an airhose, pull the carb apart to see if the float is sticking or if the carb is plugged up. Again the airhose is useful to blow out the crud. It only takes a grain of sand.

I really don't think the engine internals would be the problem with the symptoms you have. If it was it wouldn't start so easily again.

Start with the easiest first.