Adjusting valves BS twin OVH???

Having trouble, 400 hours, po never did anything including change oil or filter. Went to u-tube and several about single cylinders, None I could find on twin. It's on hasqvrana LO21H48F if it's any help. Found out intake is .004 & exhaust is .006.
Have nothing that small, so next payday will buy feeler gauges, and I'm thinking the bent ones??? Will a pencil in spark plug hole get me to top dead get me close? Ant help appreicated. Thanks
 
Check out the valve setting procedure for your engine, specifically by model number for setting the valves. It's common to have to set the crankshaft position so the piston is a certain amount (1/4", for example) down, past TDC.
 
I take the cover off. turn the engine until whichever cylinder is on compression, then move the magnet on the flywheel until it is just past the pole legs on the ignition module. This gets you part way down the cylinder on the power stroke and off the compression release. Then set the valves. I usually use a feeler gauge one thousandth less than spec. When you tighten the setscrew it opens up the setting a tiny bit and then is about dead on.
 
Setting valves depends on model of eng,on intek v twin valves set with piston AT TDC,on vanguard v twin valves set with piston 1/4" PAST TDC.
 
Thanks & Good Evening.
Yes, i should have mentioned it's a VanGuard Series. Now, bent or straight feeler gauge. I've yet to open value covers, are the gaskets pretty forgiving or just order new ones. Thanks, as I could almost hear the grass "growing" this evening!
 
As with most of us that work on eng/do mech work wee all have our own personal preference for tools we use for different jobs,as far as a feeler gauge I have both straight/offset,more often than not I use the straight gauge most & possibly once a yr for offset,if you only use gauge once/twice a yr there is no need to spend a large amount of $$ on quality feeler gauges(stainless or brass)if you're lucky & have a harbor freight store close to you they have a good quality steel straight gauge item# 32214 for $4 and will do for most shade tree mech & should last a lifetime for most people,just keep blades oiled & store in a plastic bag to prevent rust.The above is just my personal opinon,others may differ.

As for valve cover gaskets I personally would buy/install new gaskets as they aren't that expensive,many times valve covers are bent/distorted due to owner trying to reuse compressed/damaged gaskets by overtighting screws/nuts allowing covers to leak with old/new gaskets(tighten nuts to 20 in lbs)

As has been said get a service manual for eng either from local mower shop,briggs website or goto ebay & search briggs manual cd & get a cd that has all briggs eng on it($8-$10) as the vanguard eng is a long running series eng & over the yrs the rocker arm style/material has been changed 3 times,the aluminum rocker arms should be checked for crackes & regardless of rocker arm style the exh pushrod should be checked for mushrooming or bending as rod is aluminum & can be a problem on all series eng,the intake rod is steel,don't mix up the rods if you remove both.Set intake/exh valves to .005" clearance.
 
The B&S v-twin in my Ferris zero turn didn't start good from the beginning. Always acting like the battery was bad. I gave in and bought a new battery, which didn't help. Finally, my dealer says-"check the valves". What?! Yes, check the valves. OK. Turns out the owners manual has it all in there. Because of a built in compression release, one valve is set much tighter than the other. Some jerk at the factory had set all valves about the same(.012"-.014") Which effectively negated any compression release. If I remember, the tight valve setting was more like .004"-.006". Amazing how well some things work when operated as designed! No trouble with gaskets. It was a quick, simple fix. Now why didn't the dealer just tell me about four years sooner!?
 

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