8N will not start

8N quit running. Replaced carburetor, points plugs, wires and condenser. Getting fire in all places and getting gas. Any ideas?

Did you get the plug wire put on right?

Is it 6-volt or 12-volt or EI? Age and condition of the battery? When was it tested, and not just charged? Front mount or angle mount distributor? Does the engine crank at all? Why did you replace the carb? The carb is one of the parts that was designed to be rebuilt, not difficult, just time consuming. Got spark, or is that what you refer to as 'fire'? Getting gas to the carb -how did you check? "...Replaced wires..." - the entire wiring harness or do you mean just the spark plug wires? Do a systematic problem solving procedure to determine the root cause before you just start replacing parts.

Tim Daley(MI)

8N quit running. Replaced carburetor, points plugs, wires and condenser. Getting fire in all places and getting gas. Any ideas?

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Welcome to the forum! Glad to have you!!

You have fallen into the same trap as a lot of other well intentioned owners - I replaced everything and now nothing works.

As TimD prompted, troubleshooting must be done as a logical process of elimination. Simply stated; an internal combustion engine has a triangle of requirements; fuel, fire, and compression. Remove any one of those and the engine won't run.

Check fuel delivery first as it's free and easy. Pull the drain plug from the bottom of the carburetor and let the fuel drain for about a minute. What you're looking for is a constant flow of gas. If you have a restriction; it will flow steady at first (draining float bowl) and then begin to dribble.

Next is fire. Take any old spark plug and open the gap a good 1/4". Pull one of the spark plug wires and insert the spark tester you just made and ground it to the block. Turn on the ignition and hit the starter. If your ignition system is functioning properly, you will see a blue/white spark. An orange flash indicates a weak spark and will require further troubleshooting.

Compression is the last leg of the triangle. That is done with a compression gauge. But let's verify fuel & fire before going further.

Don?t guess at the cause of the problem; guessing can get expensive. And leave you breathless chasing every guess.......it could be this, it could be that......just troubleshoot the problem and leave the guess work for buying Lottery tickets. And do not buy a new part for the tractor until you can answer this question: how do I know the part on the tractor is defective?

6v or 12v? Front or side distributor?

Check for spark and fuel. (see tip # 13)

You need to answer 2 questions before you do anything else:

With the bolt in the carb bowl removed and the gas on, will the fuel flow fill a pint jar in less than 2 minutes?

Next, get out your adjustable gap spark checker * , open the gap to 1/4", hook it up, turn the key on and crank the engine. Does the spark jump 1/4"? Post back with the answers.



* Don't own an adjustable gap spark checker? Buy one! Not a test light! Until then, take an old plug, open the gap 1/4" ground it to the head & look for spark. It?s not the color of the spark that counts; it?s the distance it jumps. https://www.amazon.com/AMPRO-T71240-Energy-Ignition-Tester/dp/B00A8FO87S/ref=sr_1_fkmr1_4?ie=UTF8&qid=1513273147&sr=8-4-fkmr1&keywords=ampro+spark+checker
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