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I have a Briggs and Stratton 16 hp OVH i/c Engine that I put on my craftsman yt3000 mower but for the life of me can not get it to run right it surges pops threw intake overall just runs terrible and I am at my wits end with this thing any help appreciated i may try to get a vid of it running and upload it.

Things i have done.
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Cleaned carb 4 times.
Adjusted valves few times
cleaned out gas tank.
New head gasket.
Checked the keyway.
Compression i think was like 130 ish

here is a vid of it running

Engine model number? should be stamped on the valve cover....

Jws123 said:

I have a Briggs and Stratton 16 hp OVH i/c Engine that I put on my craftsman yt3000 mower but for the life of me can not get it to run right it surges pops threw intake overall just runs terrible and I am at my wits end with this thing any help appreciated i may try to get a vid of it running and upload it.

Things i have done.
-------------------------------
Cleaned carb 4 times.
Adjusted valves few times
cleaned out gas tank.
New head gasket.
Checked the keyway.
Compression i think was like 130 ish

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Try this, put the choke on SLOWLY as it's running, and see if it smoothes out at any point.

mower king said:

Try this, put the choke on SLOWLY as it's running, and see if it smoothes out at any point.

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At high rpms i put the choke almost all the way that is when it makes the most diff and it does smooth it out pre good at idle it still pops tho.

Jws123 said:

At high rpms i put the choke almost all the way that is when it makes the most diff and it does smooth it out pre good at idle it still pops tho.

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That generally means it's starving for fuel. Could be partially plugged fuel lines, fuel tank outlet, fuel filter or carb.....start with blowing out all fuel lines then, proceed up the list, if needed.

If blowing the lines out don't work,i would replace the fuel lines, they can start to fall apart and can clog things up on the insides due to that EVIL Ethanol.....

mower king said:

That generally means it's starving for fuel. Could be partially plugged fuel lines, fuel tank outlet, fuel filter or carb.....start with blowing out all fuel lines then, proceed up the list, if needed.

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I had the carb and lines off like 100 times already never had this much trouble with such a simple engine.. unless there is something i am missing inside the carb. Does anyone know a good aftermarket carb that has worked for them? debating on getting a new one but oem is like $120 thats more then i paid for the mower lol.

Scrubcadet10 said:

i would replace the fuel lines, they can start to fall apart and can clog things up on the insides due to that EVIL Ethanol.....

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I ran it on a external tank and lines that i had to test that no diff.

Sometimes popping through the carb can also mean valves out of adjustment or a valve train timing problem also, besides the carb......really need to try to isolate the problem or it's easy to chase everything, and get nowhere!

Always check spark plug 1st, if it don't fire right, not much else works right.....and it's super easy to check / change!

Valve clearance.... is that what you set them at? basically .004" and .006"

A couple things to check also.

• Is both rocker arms moving the same amount. A worn exhaust lobe on the camshaft can cause back pressure at the carburetor. I just one this that ran extremely poorly and actually sounded like it needed a muffler until I pulled the air filter and then it had back pressure coming out of the intake. I then check the rockers and found the exhaust barely moving. New camshaft fixed the problem.
• Another possible source is the intake seals. I had one last year that that sounded like it was sneezing and the o-ring at the head was leaking air.

<<I had the carb and lines off like 100 times already never had this much trouble with such a simple engine.. unless there is something i am missing inside the carb. Does anyone know a good aftermarket carb that has worked for them? debating on getting a new one but oem is like $120 thats more then i paid for the mower lol. >>


I'm not an Xprt, but when you find yourself doing the same task repeatedly, it's probably something else that's the problem.

I found myself with a similar problem that led me to believe the engine was being starved of fuel. Naturally I cleaned out the carb repeatedly, cleaned out the fuel tank, replaced the fuel line -----no improvement.

So what's left? As it turned out, the intake manifold that carried the fuel/air mixture from the carb to the cylinder was cracked. That allowed fresh air to be sucked into the cylinder rather than fuel/air mixture. No fuel = no power.

So I would encourage you to keep looking for possible causes of the problem rather than repeatedly performing the same repairs, hoping for improvement.

The Xperts here can probably suggest further things to investigate.

<<Another possible source is the intake seals. I had one last year that that sounded like it was sneezing and the o-ring at the head was leaking air. >>


I notice Star Tech in the previous post suggests that just the kind of issue issue I described be checked out.

Will take a look at it again tomorrow il re set valves and check all seals and intake for cracks and yes both rocker arms move a lot dont think its a worn lobe.

Take off the valve cover, and crank the engine while taking a video of it.

Fish said:

Take off the valve cover, and crank the engine while taking a video of it.

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Will do also forgot to mention when i got this it had a bent push rod on exhaust replaced it assumed it was due to a backfire or something.

Jws123 said:

Will do also forgot to mention when i got this it had a bent push rod on exhaust replaced it assumed it was due to a backfire or something.

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A bent push rod almost always means a slipped valve guide. Valve guide should not extend more than 1/8 inch above head casting. Otherwise valve keeper hits top of valve guide bending push rod. IF this is the case, B&S says the only fix is a new head. I have a tried and true permanent fix as well as some others sent to me IF you want them, address below, put in proper format and remind me engine model number and what you want.
Walt Conner
wconner5 at frontier dot com

Tinkerer200 said:

A bent push rod almost always means a slipped valve guide. Valve guide should not extend more than 1/8 inch above head casting. Otherwise valve keeper hits top of valve guide bending push rod. IF this is the case, B&S says the only fix is a new head. I have a tried and true permanent fix as well as some others sent to me IF you want them, address below, put in proper format and remind me engine model number and what you want.
Walt Conner
wconner5 at frontier dot com

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Yea i saw that on few other posts when i took it apart that people said valve guide slips was not the case on this one i checked when i replaced head gasket I will get a good vid when i take the valve cover off again

Re adjusted everything today new gaskets still runs like shit pops threw intake However i got the blades today so i decided to just run it i cut the grass for about 2 hours it appears to run steady when under load blades on and moving it cut the grass no problem as soon as the load is gone its back to reeving up and down and pops.

Sold it il never buy a mower with this style engine ever again second one with this engine ive had the same issue i tried everything.