I have had starter checked OK, Battery good, leads good, carb good, fuel changed and lines good, cleaned out distributor head good,breakaway in shaft changed,spark plug changed, oil changed. It will turn over slowly but not start. Has fire at plug and fuel at carb. Need help. What should I try next?

You eaither have one of two problems... bad solenoid... or a defective starter.

Who determined it was good and how.

I had a defective starter that cranked slow... eventually it cooked the solenoid when it got to the point it couldn't pull the engine any more.

New starter cranks the engine twice as fast as the old one ever did. And I think your engine may use the same part # my 20hp took.

Thanks for help. I had starter checked at starter shop. They said it was OK. I can't seem to find solenoid. Followed wiring as far as I could from starter but still could not find it. Any suggestions.

Follow the big fat red wire back from the starter. On mine the solenoid is on the right side of the tractor under the battery tray on the vertical panel.

I paid $40 shipped for a new one on eBay. Simply way to prove it is a jumper cable from the + terminal on the battery to the solenoid post to the starter. If it doesn't crank, then it really does have a bad starter, if you find loose connections tighten them then retry it. Vibration may have just losened a nut.

Found solenoid. Checked good. Put another starter that was known good on and still same problem. Any other suggestions. Thanks again for your help.

Look at it this way... you have a battery, a fat wire to the solenoid, which is just a relay.. another fat wire and the starter.

If you have a battery that provided enough current... cables that aren't shot, a good solenoid... and a good starter, then its got to work. Because you are getting something.

Back to square one... was your battery load tested? Outside of a seized engine, there really isn't much else it can possible be.

Changed out battery to known good one. Engine is not seized. We were able to get it cranked one time with a heavy marine battery. That is when we had to change shear pin in engine. We are getting fire and fuel. This is why it is baffeling me. Timing?

Do you have any idea on how to set timing on this type engine?

Unless you disturbed the ignition system, it shouldn't need reset. If the shear pin AKA woodruf key was replaced because you sheared it off... it should have gone right back to the original timing. As far as how to reset timing on one of these? I really don't know as I've never had to do that yet. Even if the timing was off... it should still crank. And you said you are having trouble getting it to crank... which it has to do before it will ever start.

Back to the beginning. If the motor turns freely by hand, then this absolutely HAS to work if the starter is good. Get jumper cables, gron the chassis, hot to the battery, and touch the post on the starter the red wire goes to.

There is no possible way a good starter on a free engine that is good will not crank that way. You have bypassed every possible failure point in the system when you do that. Starting is another thing... we are working on a cranking problem you described.

Pull the valve cover off the front of the engine and see if the push rods are still in place.

I have tried all the above. Still no go. This mower is hydrostatic. It seems it may be trying to turn transmission as well as engine. Not sure at this point what to try now. Thanks for your help.

eaglehead : I have tried all the above. Still no go. This mower is hydrostatic. It seems it may be trying to turn transmission as well as engine. Not sure at this point what to try now. Thanks for your help.

That should not be happening. In fact there should be an interlock switch that requires the clutch/brake pedal to be depressed before it will even engage the starter. THere is also a switch on the seat that works as a dead man stich, and nothing will start of the mower deck is engaged.

Check the valves. Valve clearances get loose and compression rises making the engine harder to start. Briggs typically sets clearance at .004 to .006 on both intake and exhaust valves on newer engines. As stated, you could also have a push rod that is broken or has become unattached to the rocker arm. Also Briggs uses a kicker on the camshaft that releives compression while starting, allowing the engine to rotate more freely. I've replaced MANY camshafts on B&S single cyl OHV due to this kicker being broken. Good luck.