toro tractor wont start! please help!!!

[93JONK]

All right, here goes..... i bought a 1986 Toro Lawn tractor on ebay for quite a steal. Briggs 11HPi brought it home and stuck my jump- starter on it and got to work. at first it obviously would not fire up. i tinkered a little and could get it to fire up off of starting fluid. at that point i started checking the gas lines, which were clogged. i cleared the lines and tinkered with the carb for a while and i eventually got it to fire up off of gas, but could only get the engine running with the throttle up high. but it ran!!!! i rode it around my property for about 10 MIN but it would still only run with the throttle up high. the engine sounded great with no knocking or sputtering. i went inside and ate dinner and when i returned (about an hour later) it wouldnt even fire off of starting fluid. NOTHING. i figured that the motor was flooded and i knew the carb needed cleaning, so i removed the carb, drained the oil, and took the plug out to hopefully clear some gas out of the chamber. that night i cleaned the carb. the next day i re-filled the engine with oil, reinstalled the plug, and cranked the motor a few times w/o carb to hopefully clear any remaining gas out of the chamber. i reinstalled the carb, but did not hook the gas line up to it. i gave it a squirt of starting fluid and NOTHING. i can hear that the motor has compression. and the plug is not wet, so at this point i dont think it is flooded. i checked and i get a strong spark (ouch) from the wire to the engine, but i cant seem to get a spark between the contacts on the end of the plug when the wire is attached to it when i ground the plug to the motor. i know the plug is good, because i tried it in my snowthrower and it worked great. i am pretty sure that it is something simple, seeing as though i had it running, but i am out of ideas. please help!!

[ransley]

You get spark but not strong enough to fire the plug, it ran before, maybe a weak ignition system, mine would not fire when the motor was hot. 22 yrs old, free is a good price.

[93JONK]

so maybe a bag coild armature? could the magneto wheel be bad? i would think

[93JONK]

sorry, i meant a "bad coil armature". and i would think that the magneto wheel wouldnt go bad as that seems like a pretty simple part.

[ransley]

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Mine was bad ignition module and shorting coil, the ignition module only didnt work at first when hot then failed, but now that its cold it should work ? Or maybe the old plug wire is bad also, or could it be simpler like a saftey switch under the seat or on the transmission that is half bad allowing some juice to the coil but not enough to fire the motor, im just guessing here so keep looking.

[93JONK]

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I dont think it is any of the safety switches. i completely bypassed the seat switch and disconnected the circuit for the kill switch that attaches to the coil armature. i dont think this one has an ignition module, but i could be wrong. i am going to try and replace the coil armature. what should i use to gap the armature from the magneto wheel?

[James Sweet]

I've seen a bad spark plug cause this, try a new one, even though it works on the other motor. Also make sure the wire is not damaged.

[James Sweet]

Possible, but in close to 20 years of playing with those things, I've yet to see a bad one. Get a tuneup kit that replaces the points and condenser, double check all the wiring, particularly the one to the ignition switch. Sometimes water gets in the switch and shorts the kill wire to ground.

[James Sweet]

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I can look in my B&S service manual when I'm at home.

Did you check the points? They're usually under the flywheel, those and the condenser commonly corrode or fail.

[Ernie Willson]

It could be that the ignition system is not up to voltage. There are a variety of reasons for this as mentioned by others here. I'd try closing down the spark gap to a minimum (say 0.010 inch or less) and trying to start it again (at full or near full throttle). If it starts then you should look into fixing a weak ignition system. If it doesn't start then (most likely but not certainly) your problem is not with the ignition.

EJ in NJ

93J> All right, here goes..... i bought a 1986 Toro Lawn tractor on ebay

[93JONK]

it's not a bad plug, because i checked my snowthrower and this plug fires it up no problem. i picked up a new armature for cheap, and i will see if this fixes the problem. also, i will try closing the gap on the plug. from there i guess i will take the flywheel/magneto off and check the points and condenser, but what am i looking for?

[James Sweet]

Corroded points. They're cheap enough to replace, tuneup kit has the points and condenser. Use a feeler gauge to set a .022" gap with the points open. It's very common for points to corrode when the engine sits.

[Ernie Willson]

First try the sparkplug gap trick. When voltage is low the spark cannot make the large jump. Decreasing the jump can get a small spark through. Usually, any spark that can jump the gap (when installed in the cylinder) will run an engine, although it will not run well at low loads.

I assure you that if you pull the flywheel/magneto off you will immediately see the condenser and the points. You cannot really check the condenser. Check out the points for being properly adjusted (gapped), and pitting. If this were my machine, since I'd gone through all the work of getting the flywheel off I'd replace the condenser and points regardless of apparent condition.

I'D ALSO REPLACE THE FLYWHEEL KEY SINCE THIS HAS CAUSED SIMILAR PROBLEMS FOR ME IN THE PAST. If the key is partly sheared then the spark timing can get messed up. The key can partially shear (without completely breaking) if the blade stops very abruptly, like when hitting large rocks etc.

HTH

EJ in NJ

93J>> It could be that the ignition system is not up to voltage. There are a

[93JONK]

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cool. i am going to replace these either way, because it seems like it is an easy way for me to have problems in the future if they arent already shot. i assume that the easiest way to take the flywheel/ magneto off is to drive two long bolts into the threaded openings adjacent to the crankshaft?

[ransley]

Before going on and replacing all the hard expensive stuff first do more basic stuff, I have seen a plug that will fire out of the motor and even in the motor but it wont take any load since a lousy plug wire was bad. To fire gas, start, run on choke and accelerate takes more juice than to idle. A bad wire, plug, corroded connection, can make it not get volts when needed, under load, it just happened to my car, one cilinder missing under load, it was a bad plug wire. An old machine, I would wonder about the flywheel key, it sets timing, if they hit enough rocks that might be the issue, timing off.

[James Sweet]

Happens in conventional mowers, but is unlikely in a tractor as the blade is not directly driven. If you replace it, do use a proper aluminum key, a steel key defeats the purpose.

[James Sweet]

There is a puller tool that uses those holes, it's not terribly expensive, but you could make something I suppose. I have a generic puller that I use, but in the past I've used a piece of steel square stock with a couple of holes drilled into it, rest that on the crankshaft and put the bolts through it into the holes in the flywheel.

[93JONK]

Just found out the engine does not have condenser or points according the the illustrated parts catalog. so i guess that it is either low voltage from the armature or bad timing. i'm going to check both of these.

[James Sweet]

That would be their "Magnetron" ignition, it's a small module pressed into the armature, later styles have it built into the assembly.

[ransley]

Then it has an ignition module that replaces points condensor and can cost 40-100$, And it has a coil, start with the plug wire- coil, it can be Ohm checked, If you just do the replace everything deal, you may replace everything.