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Briggs vanguard valve adjustment process and aftermath


mike_sdak

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mike_sdak
Posted (edited)

After freeing up the exhaust valve, replacing the bent pushrod and adjusting the valves, and mostly cleaning out my blower housing....I fired up my vanguard 23.  It started fairly easily, but sounds a little louder than before.   I can't put my finger on it, almost sounds like a knock or something?  Sounds a little harsher and louder than normal.

My first thought is: shoot, maybe I adjusted the valves incorrectly....I gently pushed the rocker down onto the valve when checking the clearance, because there was a little play in the rocker itself.  On the opposite cylinder, I turned the adjuster while the 0.005 feeler gauge was between the valve and rocker, without applying force to the top of the rocker.  When I was satisfied, I locked the adjustment. 

What would the symptoms of too loose or too tight valve gap be?  

Or could it be something else?

I hate to pull the valve covers again... I used a healthy bead of RTV and it's set up nice.

PXL_20240423_012140017.thumb.jpg.31373d5c47fc8345f1446759e3c442d9.jpg

Edited by mike_sdak
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David Barkey

Did you measure the height of the valve guide ? I have done them before where they moved the guide out of the head aways . I was able to drive it back in , The biggest thing is to make sure all the fins are clean . Over heating is what causes this issue . Carb issues can cause the over heating as well . If you have the 2 barrel carb on that , put seal kit in it and change the intake seals .

 

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SmilinSam
Posted (edited)

@s_stephen does all my valve adjustments, maybe he can put his 2cents in...

Edited by SmilinSam
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s_stephen

as long as you followed the adjustment procesure properly and both valve adjustments are good then i would guess the valve guide had moved in the head. I have seen this multiple times and it causes a knocking sound as it is now causing a interferance with other parts of the valvetrain. could explain what bent your pushrod to begin with.

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mike_sdak
16 hours ago, David Barkey said:

 If you have the 2 barrel carb on that , put seal kit in it and change the intake seals 

Not sure what you mean by intake seals?  

@SmilinSam @s_stephen: the valve guides seemed to be ok.   Apparently, I misadjusted the valves the first time around, they were way too loose!  I got extra practice on adjusting valves.  In the end, it sounded pretty decent.

I also took off some tin and it's cleaned up pretty well now. 

Thanks for all your help guys.  And I especially am thankful for @SmilinSamfor the breather assembly he sent to me last fall, fits perfectly!

 

 

 

 

 

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David Barkey
Posted (edited)
11 hours ago, mike_sdak said:

Not sure what you mean by intake seals?  

@SmilinSam @s_stephen: the valve guides seemed to be ok.   Apparently, I misadjusted the valves the first time around, they were way too loose!  I got extra practice on adjusting valves.  In the end, it sounded pretty decent.

I also took off some tin and it's cleaned up pretty well now. 

Thanks for all your help guys.  And I especially am thankful for @SmilinSamfor the breather assembly he sent to me last fall, fits perfectly!

 

Some of those B&S have square oring seals where the intake meets the head. They shrink and leak epsially on the plastic intake . Glad to see you have it resolved .

Edited by PhanDad
Moved response out of quote “box”
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