9hp briggs--pull starting is very hard--then seems piston is only making one or two cycles--is like very high compression--

If the unit is older it could have heavy carbon in the cylinder heads, it could be a ring sticking and binding, do a compression test. Compression is high or mechanical binding.

Could be a number of things like valves worn piston rings worn..try adding sooting that restores piston and cylinder surfaces..I use a product called restore. Does just that ..works well for me...you can get it at any if the local auto parts store..just enough for you oil capacity..read the instructions..good luck..

Try some penetrating oil through the spark plug rotate the piston several times and re-apply the penetrant. Lean the saw sideways with the fuel side down and the exhaust side up, overnight.
Pull the start cord (the next morning) several times. Give the cylinder a quick shot of starting fluid and re-install the spark plug.
Should start!
Best regards, --W/D--

sounds like you have a bad set of rings on one cylinder,or a bad valve set.
the stronger compression cylinder will burn richer due to the fact that the lower compression cylinder isnt pulling a hard enough vacumme to draw in all the fuel that is dumped into the intake.when the good cylinder makes it intake stroke it pulls in the excess fuel and a fresh amount from the carb.

im leaning more towards the valve train on the bad cylinder due to the white smoke comming from the carb,if the intake valve isnt seating properly,you will have compression escaping,back feeding through the intake.but yoy should hear a popping along with the smoke,everytime the engine fires that cylinder.
hope this info helps you.

4 stroke
#1 intake stroke
exhaust valve closed,intake valve open.as the piston is on its way to the bottom of the bore,it creates a vacumme.drawing in the air/fuel mixture from the carb.when the piston hits the bottom of its downward travel,the intake valve closes,then the next stroke comes into play.

#2 compression stroke
after drawing in the air fuel mixture,the intake and exhaust valve are both closed.the rotating momentium pushes the piston back up the cylinder,compressing the air/fuel into the cylinder.

#3 power stroke
(depending on the timing)when the cylinder reaches top dead center (tdc)in the bore.the spark plug ignites the fuel,which causes the air/fuel mix explode.that explosion forces the piston back down into the bore.when the piston travels down,this stroke is completed.

#4 exhaust stroke
after the power stroke,the piston then travels back up the bore,while opening the exhaust valve.the moving pistion then pushes the exhausted air through the exhaust chamber and out the muffler.

then the cycle starts over again.
so if you have a valve thats not seating properly,on compression stroke you will have loss of compression,on the power stroke,loss of power....forcing that ignited fuel back through the valve that isnt seated corectly(if intake) you will get white smoke and a poping sound from the carb.on the exhaust stroke it will sent exhausted air back through the intake aswell.

once again i hope this helps,id dig into the valve train on that cylinder.

nick

Could be timing but also could be the compression release isn't working. I'd download a manual from the Briggs & Sratton web site http://www.briggsandstratton.com/maint_repair/manual_and_more/

Yes. You need a new top end. Being very hard to start, and having no power, sounds like you have no compression left. You need a new Piston Kit. Wiseco make one for your model.
This is a very high reving little bike, the piston and rings in them dont last very long.

No it doesn't have a decompression system. Sounds like a valve is stuck open. Need model number for more details.

Hello rfrazierL

>>From your Description it Sounds like the Valves Require Adjusting.
>>The Following is a Basic File I made for Setting the Valve Clearances. Any Input is Appreciated.
>>**I Do Not Use the Setting Called for by the OEMs. I have Found that the Following Works Best.
>>Remove the Valve Cover (on the Dead Cylinder for Twin Cylinder Engines).
>>Check the Push Tubes and make Sure they are Not Bent.
>>Set the Cylinder you are Setting the Valves on to Top Dead Center on the Compression Stroke When Setting the Valve Clearance. Now Loosen the Valve Adjuster Lock and Using a Blade Style Feeler Gauge, Set the Intake Valve Clearance to .004in -.006in and the Exhaust to .006in - .008in. Loosen and Tighten the Rocker Arm and the Feeler Gauge is Placed Between the Rocker Arm and the Valve Top where the Rocker Arm Pushes on the Valve.
>>***BE SURE TO TIGHTEN THE ADJUSTER LOCK AFTER YOU HAVE THE PROPER VALVE CLEARANCE***
>>I have had Better Performance Out of the Mowers and Less Burnt Valves Using these Settings. Be Sure the Piston is at TDC on the Compression Stroke.**
>>If you Remove the Valve Cover and then Turn the Engine by Hand, you can Watch the Intake Valve Movement. When the Intake Valve Closes, the Piston will Just Starting the Compression/Power Stroke.
>>On Some Engines you can Us a Straightened Coat Hanger and Feel the Piston.
>>Be Careful and Don't Jam the Wire in the Cylinder. Usually the Piston will Push the Wire Out of the Spark Plug Hole with No Problems.

Respectfully

John

check starter pulley .it may be warped and hard to pull under compression .also if chain is very tight it can put pressure on crank and cause hard to pull

you need a new had gasket or a new piston