Crftsmn DLT3000 w/18.5hp B&S OHV Intek plus mod. #917.275810. Engine won't turn over. When key is turned starter engages and begins to turn flywheel but as soon as resistance is met it bogs down like a week battery. If you hold key over flywheel turns in short fits until past compression stroke and then turns free until resistance compression begins again. However, holding key causes starter to smoke and burn. Replaced battery and starter but still have problem. What's next? Ted.

 

Sounds to me like the valves are out of adjustment. Try pulling the spark plug and see if the starter turns the engine over properly. If it does it is probably the valve adjustment.

 

possible bad connection at one of the battery cable ends/ like where the ground cable attatches to frame- ect.

 

Thanks new, I'll check that. Ted.

 

Jl, the mower runs fine once it does start. I have on occassion been able to get it to start by jumping it but there doesn't seem to be any rhyme or reason. That's why I first changed out the battery thinking it was weak, but still the same problem and sometimes if I would leave it hooked up to a charging system or jumper cables and held the key over it would, after several seconds, crank over one good enough time to start. Unfortunately too much of that burned up my starter and I wound up replacing it. But on the few occassions that I have been able to get it to start it seems to run really well. No sputtering or missing or backfiring and so I couldn't imagine the valves being out, but I will get try your suggestion. Ted.

 

That really sounds like a compression release on the valves. It will hold the exhaust valve open slightly until you're just past TDC on the compression stroke. If that's not set properly the starter will have to pull against full compression = bogging down on the start. After being started the engine would run normally.

I would make sure the valves are adjusted properly. That usually takes care of it.

 

I agree, you need to adjust the valves. This is recommended periodic maintenance for your engine and if neglected long enough, it will render the compression release inoperable (which is the case here). It also harms the camshaft by allowing enough clearance that the cam lobes "slap" the lifters every time around and it wears the lobes down. I've been having to replace a lot of briggs cams lately, especially on the newer chinese built engines.