Briggs popping

[Auto Doc's]

Hello ILENGINE,

I've watched the initial video a couple of times and that popping back into the intake is indicative of badly worn cam lobes or a valve adjustment that was not done correctly. If this original cam design has press on lobes, there may be a chance that a lobe slipped on the shaft.

 

[wekjo]

Might be partial blockage of fuel. Blow some air through line backwards to tank.

 

[Zedo]

Hello ILENGINE,

I've watched the initial video a couple of times and that popping back into the intake is indicative of badly worn cam lobes or a valve adjustment that was not done correctly. If this original cam design has press on lobes, there may be a chance that a lobe slipped on the shaft.

Briggs specs on your engine should be .002-.004 on your intake valve and .005 - .007 on your exhaust. Most Briggs this is standard on small engines. 1/8 inch would be way too much gap. Compare thousands of an inch to a piece of paper, for instance paper is .003 thick.

 

[wekjo]

Might be partial blockage of fuel. Blow some air through line backwards to tank.

Take fuel cap off first, leave it off and test drive. Cap has one way vent in it. If vent stops working becomes a fuel supply issue. Costs nothing to test these issues before you start wrenching and open your wallet.

 

[Grasswhore]

Is there supposed to be a sleeve spring from the governor to the carb linkage? That carb flange seems to wiggle a lot, like that spring tension would modulate that.

 

[LMPPLUS]

I think you you have a head gasket starting to blow thru.

 

[Etbrown44]

How aboit a possible slipped key on the flywheel?

 

[ILENGINE]

Briggs specs on your engine should be .002-.004 on your intake valve and .005 - .007 on your exhaust. Most Briggs this is standard on small engines. 1/8 inch would be way too much gap. Compare thousands of an inch to a piece of paper, for instance paper is .003 thick.

I think you misunderstand what was being discussed. The 1/8 inch was not the valve clearance gap but how far the cam lobe lifted the valve when it opened.

 

[Have_Blue]

Sounds like it's running lean. Pull the choke out just a tad snd see if it runs better. If so, try fuel injector cleaner or check the carb for sludge or trash.

 

[outdoorpowermike]

Did you do a compression test? Popping at high rpm is because intake valve is not seating properly, or valve seat and guide are not where they should be. Even with good compression you will still get popping.