briggs and stration 17,5 hp hard to start

I have a briggs 17.5 hp engine on a husky 42'' mower and what the problem is when u crank the engine over and it comes to the compresson stroke it stops turning I know that it sounds like the valves need adjusted but I have done that and no change it is a hydrosatic trans if u use the dump valve on the trans it will start better sometimes thanks for any help Scott
 
1. Have someone load test your battery. If it is o.k.-It doesn"t go below 10v under load,

2.Clean the battery connections and make sure they are clean and tight. If that doesn"t do it:

3. Try going directly to the starter with jumper cables. Hook + from battery + to the post on the starter, Hook - to the battery - and touch it to the engine case. (In case you have too much resistance in the solenoid or battery cables or a poor ground connection)

3. Check the valve settings again. If that doesn"t do it,

4. Either your compression release is broken or your camshaft may be worn to the point that the compression release ramp is gone. Depends on which style camshaft you have.

Perform the above tests at your own risk!!!!And only if you feel O.K. doing them.
 
You could be on to something about opening the dump valve. Try removing the belts and see if it turns over normally. If so, something could be binding in the hydro, or a bad idler, or...

When it's running, and you bring the hydro to neutral, does it always stop, or does it try to creep? Could be a linkage adjustment or excess play?
 
What's the mod# of eng?

Depending on mod# of eng some briggs ohv eng valve's are set with piston AT TDC on others valves set with piston AFTER TDC,in addition check pushrod's,some mod eng have a history of bending/mushrooming push rods.

You said eng sometimes started easier with dump valve open,check your clutching mech,same may be binding/sticking due to rust/dirt or some mech problem,on most/all belt drive lawn tractors clutch/brake pedal must be depressed/locked down to start tractor this also disengages belt to hydro unit check that belt being completely disengaged & not turning when cranking eng,regardless if mower deck a manual engage/elect pto confirm that deck not being driven when cranking eng,starter is not designed to crank eng with driven loads engaged.

Before trying to start eng remove plug(s) & crank eng 3-5 sec,reinstall plugs,crank eng,if eng now turns over or fires/runs & starter doesn't stall on compression the the most likely cause of problem is float valve in carb leaking flooding eng when at rest & hydolocking piston(s)on compression stroke,this is a common problem on many mod briggs ohv eng.

If all loads on eng being disconnected,valves set correctly & eng flooding not a problem,then as has been said check electric's on tractor.if that not the problem then acr may be worn/broken.
 

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