If the starter is spinning, but the flywheel (and the screen on top of the engine) is not turning, then the problem would most certainly be the drive gear on the starter.

If the starter tries to turn the engine, but doesn't have enough power, then you may need to adjust the valve lash. These motors have a compression release that works off the camshaft and must have the valves properly lashed or it will not crank. If this is the case, you will hear the click of the solenoid, and you may see the flywheel turn somewhat but it will not rotate all the way around. Also, the starter will NOT be spinning free of the flywheel.

Let us know which one of these your engine is doing, and also post the model, type, and code off the engine. These numbers are probably on one of the valve covers.

thanks for the reply
model engine is 461707 type 0145et code 9906165b the solenoid clicks starter clicks and the gear on top tries to turn the fly wheel it moves forward about 2 to 3 teeth then does not move solenoid keeps making almost a wineing noise flywheel can be turned by hand but very stiff
hope this helps
thanks for the input

Well, that is an opposed twin flathead motor. No adjustable valves here. If I were you I'd check all the battery cable connections, even the ground connection to the frame. You can also check the voltage drop of the cables and solenoid. It doesn't take too much voltage drop to cause problems.

Take a digital voltmeter and set it to the DC Volts scale. Put one lead on the battery (-) terminal, and the other on the metal case of the starter. Try to crank the engine while noting the reading. Next put one lead on the battery (+) terminal and ther other on the cable post on the starter. Crank the engine while noting the reading. A drop of more that 0.5 volts needs to be fixed.

Just a thought here, if this checks out good then try to crank it with the belts removed. I have had a belt driven component go bad and cause enough drag to prevent the engine from cranking.

there is a voltage drop from the battery i get 12 v at the starter post when cranking i get half that what could it be I tried 3 new solenoids still what ever could it be

Another couple of things. Condition of the battery cable ends. Corroded or loose cables can cut your voltage in half. And yes be sure grounds are happy. You can use your jumper cables safely to go from the battery to the starter direct and confirm a lot. Remove the battery cables. Pos bat to the lug on the starter. Neg bat and the momentarily ground the cable end on a safe (not oily, no gas present) spot on the chassis or engine block. If it does crank it, check all connections at the battery and solenoid and be sure the solenoid is grounded well if it is a 3 pole especially. This doesn't crank it, you have starter motor or engine issues. Is is possible that the engine is hydraulically locked? (Oil ore fuel above the piston? ) You may want to remove the spark plugs and try turning by hand. If you crank with the starter, be sure to either do it with the switch off or ground the wire going to the coil. Spark and a lot of fuel shooting out of a sparkplug hole don't play well together.

itried to wire direct and it would not start i removed the spark plugs turned the fly wheel real easy aroun a few times
put plugs back in and the strater actually turns the fly wheel to the point of the magneto and where the contacts of the fly wheel met and it stops i have to take the plugs back out turn the wheel and it will do it again if i do not take the pugs out and move the wheel it only moves one tooth at a time whats up with that??
thanks for all the help so far

look at my reply on the tractor forum, decarbon your heads
and mow some grass, that is my guess at the problem.........

Wired it direct means? Did you use a set of decent jumper cables? Have you verified your battery is fully charged? New may or may not be. I suppose it could be carbon build up. It all depends on things like oil consumption, head or cooling fins ever been cleaned before ,# of hours. . . You do need to buy new head gaskets if you choose to do this. There is a left and a right. I had 1 compression release( Cam) problem ever on these

fixed it
I think the motor was locked up after I released it taking the plugs out I also cleaned the contacts of what I think is the magneto check again for loose wires and cleaned off the ground terminal wire for the battery I jumped the battery and we got er started I think I wore the battery down from trying to start it over and over works great mowed the lawn and I'm a happy camper
thanks for all your help and input
have an awesome day

"I also cleaned the contacts of what I think is the magneto"

IF what you cleaned is outside the flywheel, not under it, those parts are not supposed to touch. IF this is an electronic ignition unit, there is supposed to be .010 - .014" air gap between the flywheel magnet and the coil laminations.

Walt Conner

i have the same prob with probably almost the same craftsman
B&S mower. battery tested at 12.4v, about 3.5v coming off red wire of solenoid. i too changed to a new solenoid and now i here a whine everytime i turn over the mower. It turns the flywheel about one or two times and thats it.

"with probably almost the same"

WHICH engine? Almost doesn't count!

Bill,

17.5 HP model 917.272670 Briggs #31C707 type 0230-E1
I.ve had the battery on a charger, now i have 13.25 volts
coming into solenoid.

Since that's an OHV engine, check the valve lash.
Too much lash and the compression release doesn't work.

Your engine is an OHV single. The OP's was an opposed twin flat head. Not even "almost".:-)

.004" intake
.006" exhaust
Make sure the piston is 1/4" PAST TDC.

Hmmmm, guess i better spend some money and take it to someone. I had enough trouble changing out the solenoid. Thanks for the info...

How do I check and/or change the valve lash?

"How do I check and/or change the valve lash?"

On what? I don't see where you have posted your model number but perhaps I missed it.

Walt Conner

Hi,
Sears Craftsman
15.5 B & S , 917.256531 ,14 years old

Turn key -whining noise and starter spins ,but will not engage with flywheel.
Could it be battery?

Battery connected backwards? Fully charged? More than 2 years old?

OR starter pinion gear teeth stripped.

Walt Conner

I realize this is an old thread, but it may help someone else to know that these starters have two different gear options. Some have 14(?) teeth, some have 11(?). Not sure about the number of teeth, but count the teeth on your old starter gear and be sure the new starter has the same amount. You can swap the old gear onto the new starter if necessary. With the wrong gear, the starter will bind up because it doesn't mesh with the teeth on the flywheel correctly.