Small Engines (Lawn Mowers, etc.): Briggs engine will not start, intake manifold gasket, briggs and stratton

Question
Hi Paul
I have just rebuilt a Briggs and Stratton engine after it had been run with low oil and the conrod seized on the crank pin.  All seemed to go well with the assembly, although I have no workshop manual, but the engine will not fire up.  It sounds as though it is trying to fire as I crank it on the starter, but it won't pick up and run.

There is a good spark.  The carb seems to function OK - there is petrol in the float chamber and the float-chamber valve works fine.  The main jet is clear of any debris.

I thought the timing may be out, but I have opened up the crank case and confirmed that the two timing gears appear to be aligned OK with timing dots meeting precisely.

I tried squirting ether (locally sold as a cold-weather starting aid) into the carb.  Normally, that will get anything going, but the engine did not even fire once.

There is good compression, but the spark plug does not look as wet as a I was expecting after a few minutes of fruitless cranking.  

Any suggestions please before the grass grows so high I have to hire in some sheep ?

Engine model: 28T707
Type: 1121-E1
Code: 9910057D

Thanks

John

Answer
hi john

did you time the  camshaft to crankshaft pinion gear  

dot on camshaft gear must align up with dot on crankshaft pinion gear
sounds like you have this one covered ?

dis you set the tappetts to 0.003" inlet and  0.005"  exhaust @ 1/4 " down the bore on power stroke ( this eliminates decompressor )

is the afterfire solenoid opening up  with  12 volts applied when key turned on ?

it should click , you can feel it if you put your fingers on solenoid ?

make sure intake manifold gasket is good and no leaks

were the valve ground to their seats and contact checked  ?


have look and let me know

it could be as simple as  adjusting valves @ 1/4 past tdc  as above or the afterfire solenoid not opening up  


cheers  paul