Sure you can test it. But you'll need either a 12V automotive type test light or a DC volt meter. To test the output of the solenoid you need to identify the solenoid output terminal (this terminal has the cable that goes to the starter connected to it). Attach the ground (negative) of the test light or volt meter to a good, clean ground surface (the negative post of battery is good for this), then hold the test light probe on the output terminal of the solenoid while you or a helper turns the ignition switch to START. If the solenoid is working, the test light should light up. If using a volt meter, the meter should read the same as your battery voltage. If the test light doesn't light up, or the volt meter shows no voltage, your solenoid is most likely defective. But before I would condemn it I would check to make sure that the cables are tight and not corroded anywhere between the battery and the solenoid and between the solenoid and the starter. Most of these machines also have the battery negative cable attached to the engine somewhere. Make sure the negative (ground) cable is free of corrosion and tight. A fault in the ground side can be just as bad as one in the "hot" side of a starter circuit.

Thanks, I have a 12v light tester here somewhere. My son has a meter if we need it. Nice simple set of instructions, thanks again. Will let ya know.

Is the fused lead wire on the hot side of the solenoid ( battery side) - i had thet problem with a 12HP Murray - i changed the melted old solenoid for a new one and accidently hooked the fused lead on the switched side, would click but not start. The fused lead needs to be on the hot side to feed electric to the key switch. Check for a good ground as well, thet'll keep em from starting too.
Kidd

If that engine has a compression release, too much valve lash can cause it to not engage. That makes the engine very hard to crank.

The idea behind the test light is this-
If you have a suspected bad connection, jumper the light on each side of that connection.
Electricity flows through the path of least resistance. If that's the test light, it means the connection is bad and the light will light. If no light, the connection is good.
Obviously, the circuit has to be energized during the test.
A light can be handy, because you can test from point "A" to point "D". If every thing is good from A to D, it means point "B & C" are good. If not, you can narrow things down from there.

Let me add this about bill kapaun's technique. When you use the test light in this fashion, the light will burn as soon as you hook it up to the terminals of the solenoid (with clip on one terminal and the probe touching the other terminal). As soon as the key is turned to START, the light will go out if the solenoid is in good condition. Using either technique will prove the health of a solenoid.

Found my light and hooked aligator clip to battery negative. Touch hot side of solenoid, got light. Expected to. Starter side no light. Turn ignition still no light. Put finger on solenoid and can feel click when I turn ignition to start. She's bad right?
I hated to do it, but I have company today and half a acre of uncut grass. So I jumped accross it and mowed. With all the rain in North Texas, you have to take windows of opprotunity when they present themselves. Or you could end up needing a brush hog in a hurry.
I hope I can find it locally. It's only 16.95 on sears site, but they add 10.00 shipping and handleing and it takes a week.
Thanks for the tips.

I wouldnt suggest using starter fluid either, its a great way to blow the motor up. A better way of starting the tractor would be to ground it on the tractor, and touch the starters post. Jumping the starter solenoid will eventually melt it.
Kidd

When you go searching for a solenoid, it isn't required to be the "exact replacement part" (meaning, O.E.M.). So long as: (1) it has the same terminal connections of the right size & style to accept your wires/cables. (2) it has the amperage capacity to serve your starter. (3) it will bolt in place where the old one came out. Take your old solenoid and check with mower and power equip. shops/dealers. A rule of thumb here as to amp capacity: Don't buy a solenoid intended for an engine of LESS than 18 HP (YOUR engine has HP) unless the parts guy says it's rated for use in a higher HP application as well. It's OK to buy a solenoid that will handle higher than 18 HP engines, you just don't want to go the other way. As to the mounting hole for the solenoid: You could even drill one new hole to mount it if both mtg holes on the new one don't match perfectly. The amp rating and configuration of the terminals is most important when deciding on a non-OEM solenoid. By the way, sometimes this "solenoid" is called a "starting relay" in some literature (just in case somebody calls it that, you'll know). And......be sure to draw you a sketch of where your wires are hooked up to the old one before you remove them. After you get it out where you can see the solenoid closely, if there are any ID marks, numbers or alphabet characters for the terminals, add them to the correct position on your sketch. Failing to do this simple step has gotten many a DIYer in trouble.

Thanks guys. Kidd I once had a fire trying to use gasoline to prime a car, it was scary but came out allright. Starter fluid is safer. I don't use it often, and I follow the instructions. Now my question. I don't intend to jump the solenoid often, I have seen what your talking about. Are you saying take a wire from the hot side down to the starter? This is more ford like, than chevy. Chevy had the solenoid on the starter. You had to get under the car to jump it. Ford had them on the fender well. Also liked the distributor in the front idea too.

{{gwi:327502}}

Solenoid is by the battery. Starter is under the motor. Matter of fact the guy that put the starter in had to raise the motor to do it. Note my sons expression just bolting the new drag link on last weekend......lol
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Mownie , good advice also thanks. There are several places around that repair mowers. Hope I can find one there. I once took a thermostat off the wall, took all the wires off and then read the directions. If you have done this simple task, and I bet you have, the first thing the directions say is.....DO NOT REMOVE WIRES FROM OLD THERMOSTAT YET..READ INSTRUCTIONS. That was fun, but we got it figured out.
Thanks to all.

If you have an old Ford type solenoid, just go to a decent auto parts store. Take the old solenoid with you to match up.
A solenoid for a car is bound to have "stouter" internal parts.

Ask for a solenoid for a 1975 Ford Van. It is will start a 351 CID engine, and is cheaper than the lawn mower part.

I have seen the click-crank scenario when the battery is low.

I would you might check and see how bright your lights are (engine off), and see if they vary a lot with engine RPM.

Better yet, borrow a charger and charge the battery overnight and see if that solves the problem. A brand new battery is rarely, if ever, fully charged (did the Wallmart person make you wait 20 minutes while s/he charged).

"I have seen the click-crank scenario when the battery is low."

OP said-"After a few clicks it engaged the starter and I got to mow."

That infers the battery was charged enough. After mowing, it should have been charged even more (if needed), assuming the charging system is working.

Colt- what are the numbers off the tractor & engine?

I was having the very same problem, so hopefully can save you some money. I replaced the solenoid; made no difference. Dealer said bad ignition switch; I replaced it; still nothing!! Both battery cables look very good, but since I had tried everything else, it's worth a shot. I replaced the pos cable and the engine turned, but very slowly..While trying to start it, I noticed smoke comming from the neg cable, and it was too hot to touch. Replaced the neg cable, and now the engine spins and starts like new. I wasted money on the solenoid & ignition switch....Live & learn!!!

Nobody told me a new battery needed to be charged. The tractor is a 917.254410 engine number must be covered or something, I have looked around but don't see it. I didn't get a chance today but sometime this week I will get a solenoid. I can get a charger too if you guys think that's all it needs.
It did seem funny that this problem started with a brand new battery. The one we ran down was a couple of years old, so I just got a new one. Should I take it back?

A clicking solenoid means that it is functioning properly, so don't waste your money. You are getting just enough battery power to click the solenoid, but not enough to spin the starter, as it requires a tremendous jolt. Odds are, your battery (even though new) is in a run down condition, OR one/both battery cables are faulty.

Just because a solenoid clicks does not prove that it is good! The click is only the result of the plunger moving when the solenoid coil is energized. The click does prove the the coil and plunger are functioning but proves nothing about whether the contacts are good or bad. Did you not say that when you tested it with the test light that it clicked but did not light up the light?? If it clicks but does not light the test light, that tells me it is not closing the circuit between the battery and the starter. Also, you did say that you "jumped across" the solenoid and cranked the engine to mow because you had company coming, right? I thought so. The battery is not dead. Looking at the photos I would infer that there is a very good chance the the contacts inside the solenoid are burned or corroded. In that condition the solenoid can click all day and still not send current to the starter.

"It did seem funny that this problem started with a brand new battery.:

How could you tell if it didn't crank before?
A 2 year old battery in L&G equipment is pretty suspect. If you still have the old one, you could get it charged & tested. I'm not sure if that's really worth your time considering its' age.
Here's a link for the "original" solenoid-

http://www.mfgsupply.com/m/c/31-10772ay.html
Just Google 109081X

Your engine is-
422437 TYPE NO. 0750-01

You can go to Sears and plug in the number of your tractor to get parts lists & diagrams.

My bet is on the solenoid, but do check ALL battery cable connections.

Sounds to me like a low voltage probem, not getting enough amps to the starter. IMO carb. cleaner is much better than starter fluid and gasoline when trying to prime an engine for starting. you can control the amount of fluid you are spraying into the carb. and you get the extra benifit of it cleaning your carb. I'm not a big fan of starter fluid, jumping it not going to hurt it IMO it creates a ampree path to the starter which you are lacking with bad cables, cable connections or broken/corroded wires to the solenoid or it could be a dirty/bad starter.

It has a new starter

Odd.The easiest and simplest things to check seem to be the last things checked.ie bad/loose cable connection..fuel tank empty,blown fuse etc.JMHO tbk

Thanks for all the info guys, if one of these tips doesn't work I will be surprised. Let me clarify a few things.
First Bill thanks for the motor number. The old battery was cranking away. Engine hadn't been started in a while. I knew better than to just keep cranking till I killed it. It's been raining nearly everday here and I really needed to cut the grass. When I got home an hour later, and put the new battery on it just clicked.
Oh and I didn't mean it was a Ford solenoid. I meant it's set up more like a ford with the solenoid under the hood, not on the starter. My buddy had a Chevelle and he had to crawl under his car to start it. So I used the Chevy as an example of a differnt electric setup.
From all the advise here's my plan. I will get my son's charger and make sure the battery has a full charge. Check all connections and cables. If it does the same thing, starter solenoid seems like the suspect.
I already did some of the things advised. Fuses are good, gas cap vents seem fine. Gas is new.
Thank again for all the tips, we'll find the problem.