[JTalley]

I'm honestly not sure where this would go, (sorry) so I decided to post it here. I have a Wizard lawnmower with a 14.5 hp Briggs, and I can't get it to start. I don't have a battery, so I hooked up a car battery with jumper cables. When I turned the key, it would crank until it started to build up compression. Then it would stop. I thought it was the starter, but after cleaning it up quite a bit and oiling it, I had the same problem. Someone came in and hooked up the cables the same way I had, and it fired right up. I figured I didn't have a good connection, and that would be the end of the problems. Later on I came out, hooked the cables in the same spot that they did, the exact same way, and it did the same thing it had done earlier. I've tried hooking up the cables to the battery terminals, and I've tried hooking one on the frame and one on the starter. I've jiggled them to get a better connection, tried different spots, same problem. What's going on?

 

[davidg]

get a battery for it, just clamping booster cables on does not guarantee a good connection.

next, is it OHV? if so you may need to adjust the valve lash. when it gets out of spec the compression release does not work and the starter can't turn the engine over.

 

[burnout2499]

try some ether while cranking

 

[monteman_73]

I have a Wizard lawnmower with a 14.5 hp Briggs, and I can't get it to start. When I turned the key, it would crank until it started to build up compression. Then it would stop.

Does it spin a few times, then stop? If so, chances are you don't have the best connection. Did your friend use his cables, or yours? If he used his, chances are his cables are better than yours.

Does the engine spins less than twice and stops? And if you wait a few minutes, it will do it again? Is it an OVH engine? (Over Head Valve) If so, the valves may need adjusting, because the clearance may be too great and won't allow the Compression Release to do its job. If adjusting doesn't help, then the compression release may be bad.

 

[JTalley]

It's an OHV. It doesn't spin even once- it spins until it reaches the compression stroke, and slowly turns past that if I give it a moment. He used the same cables and battery and it fired up right away.

I'm a bit nervous about valve adjustment. Is it as difficult as it sounds?

 

[davidg]

sure sounds like valve lash. you need to post the actual model and type code off the engine and someone can get you the instructions. it is fairly simple to do, you just need a couple wrenches and a feeler guage.

i'm thinking the reason it turned over for him is that he had a stronger battery charge at the time and the engine had just come off the compression stroke when he tried it. i've got a couple of OHV briggs that do this every 50-100 hours, takes less than 5 mins to fix.

 

[engine2quarters]

Just a wild thought, I wonder if the bolts that hold the motor to the frame are loose. If the battery is connected to the frame, a poor connection between the engine and frame will exhibit this condition.
It may have just been a stroke of luck that your friend got it going so quickly. The motor might have made a good frame to motor connection when you tried starting it. Check all your connections, ie. battery to pos lead, pos lead to solenoid, solenoid to starter, motor to frame, frame to neg cable, neg cable to battery (or jumper cables). Clean and retighten connections.