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Discussion Starter #1
hi all...i did away with my points and put on a solid state coil.the engine is a briggs cast iron 16hp model 326437.any way ive got good spark and gas but it just wont start. any ideas? i can shoot it with ether but still no start. it has to do with timing of spark i know . how do i get it timed right? the only thing i can think of is to move the coil bracket. i have it to the far left for gas where it was.
 

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#3 is air

You've tried the propane trick to eliminate carb issues?

It should still fire at least once (although maybe backwards) when it gets close enough.

On that size I am not sure the bracket has enough room to advance that far. You may need to pull the woodruff key to advance it enough. Move it all the way forward and see if you get anything.

Life would have been easier to keep the points; unless the arm was damaged. Having that large a mass flywheel without grinding/cutting a new keyway could be a dangerous without a cover.

The rough rule is 30° to start and then work from there. The Briggs Handbook probably has the number you need for the conversion.
 

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Actually, does yours have the adjustable rotor? I just recalled that my larger ones do. You may be able to use it to advance as well.
 

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Discussion Starter #4
by adjustable rotor do you mean a slotted bracket for advancing or retarding timing? if so my bracket is slotted.
 

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by adjustable rotor do you mean a slotted bracket for advancing or retarding timing? if so my bracket is slotted.
Like this
 

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Am I off base thinking this is a compression issue...or a clogged air filter?..Why did you switch the ignition system?...had there been a problem that you were trying to correct?
 

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Due to where the cam lobe to activate the arm to open and close points is, the coils are set in a different place than they would be for an electronic ignition.

The mechanical system has a delay until it activates, this is compensated for in the design. You have to remove this compensation for an electronic ignition.
 

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Discussion Starter #9
this engine came on the tractor I bought...previous owner had taken off the coil years ago and lost it. tractors been sitting.ive put on a new carburetor and new coil.the coil I bought was cross referenced for my particular engine from jacks small engines.after comparing it on the web to other coils that originally came with my engine I determined it was for engines without points.i bolted it up and set the air gap and had instant spark.engine just wont fire though.my internet searches indicates flywheel may need repolorizing or timing bracket needs moving.im lost. the way this engine sits in the tractor I have to keep pulling it out to take off shroud and flywheel.big pita.
 

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Discussion Starter #10
so that means I need to move the coil ? im all the way to the left now. how far should I move it ?
 

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Discussion Starter #13
yeah thats the video i was referring to about briggs polorizing flywheel. taryl mentions just flipping the coil.i think im going to try that.
 

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Discussion Starter #15
ok,so i flipped coil around and got nothing. flipped it back and got spark again.so i guess that part is right.i did discover another sheared key in flywheel.obviously i have timing problems..what would be the best approach without pulling covers off?im sure ill have to pull the head again to watch valves.i done all this once before .what am i missing?
 

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The flywheel key is aluminum and only there for alignment. The fly wheel has likely slipped. I have had this happen on two of these engines on my MTD 990s. After putting in a new aluminum key, the flywheel nut needs 145 foot pounds of torque. I use a box end wrench with a pipe extension. The crank needs to be held solid from turning.
Flywheel.jpg key.jpg
 

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ok,so i flipped coil around and got nothing. flipped it back and got spark again.so i guess that part is right.i did discover another sheared key in flywheel.obviously i have timing problems..what would be the best approach without pulling covers off?im sure ill have to pull the head again to watch valves.i done all this once before .what am i missing?
You dont really need to pull the head.

Pull your plug and drop a chopstick down, rotate the flywheel until at the top. Now you just have to determine where your valves are.

I find it easiest to pull the window and look at the springs on these engines, or if that's not convenient, pull the carb and blow into it. That will tell you if the intake valve is open or closed.

It's the rectangle with the tube hanging out for the valve spring cover window. Normally under or beside the carb.
 

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Discussion Starter #18
just want to thanks to everyone here who gave input and advice on my starting issues.much to my embarassment i wasnt torqueing flywheel nut enough. never ever thought the nut needed 145pds of torque. ive been putting it on with probably 75 to 80 ft pds.results was no start and sheared keys. torqued it down good to 145 pds and ill be danged. started right up.ive learned lesson here nd extend my thanks to everyone.
 

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Thank you for letting us know....this way ...we all learned something...that is an easy mistake to make
 

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Glad to hear it is running now. May you have continued success.
 
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