Briggs Carburetor dies when accelerating

StarTech

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Probably trying to use a smart phone. People sometimes needs a real desktop computer with a large screen.

Rust is not your friend; it is a sneaky enemy.

These carburetors are mounted on steel tanks that tends to rust a lot. This rust can even clog up unseen passage especially in the tower section. Over the years before the tanks became unavailable I had drill the tower steel plugging ball(s) and clean the passage contain within. Once cleaned out that passage has to be resealed. Even ultrasonics won't clean out the rust nor will dip cleaners.

On that many of these carburetor's towers never had a filter screen install. Most were installed by tech upon the first major repair. An after thought on Briggs part.

Also check the valve clearances as this is a very old L-head engine and the valve clearance probably at zero.

I do have one 3 qt tank left that I am saving for later use. That is if the customer will to part with $150. When they hit over $100 the customer quit buying them and I don't blame them.
 

Forest#2

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On the carburetor how many holes should be in the small pickup that fits in the shallow hole on the fuel tank.

?????????
explain.
Pickup tube holes?????
 

tim4

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I was referring to the piece with a hole in the side of it that is casted on the carburetor. I took the carb off again and sprayed carb cleaner in it again and blew it out with air and now it works fine thanks.
 

hlw49

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You may have to clean out under the welch plug on the side of the carb. part no 691742
 

tim4

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How do you remove them.
 

Forest#2

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How do you remove them.
I only remove welch plugs when all other cleaning methods fail.
If I have a replacement Welch plug I carefully drill a hole in the center to use a ice pick or small sheet metal screw to pry out the plug. Be really careful and do not let the drill bit go into the plug too deep.

If I do not have a replacement welch plug I use a very small drill bit and drill a hole in the center of the aluminum plug, carefully pry out the plug for re-use.
I re-form the plug using a piece of leather and a round ended punch.
To re-install tap the plug into place and then I have a slow drying 2 part epoxy that is non flow type that I use to seal the drilled hole and the edges of the plug. I sometimes give the re-used plug two coats of the sealer epoxy.

I usually only do this on NLA carbs that are in the category of dinosaur eggs. (extinct) and my own stuff.


Some of the pulsa jet carbs are NLA, but I see that China in now cloning some od them and for sale on flea bay for around $15.
 

Forest#2

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The reason I ask you to test with the tank completely full is:
This bypass's the long pick-up tube and the pump for such which is used to pump gas UP into the upper storage pan for the short tube when the fuel level drops below about 1/2 in the tank or below the level of the short tube.

If same symptoms with a full tank check the short tube and carb jets, diaphragm, etc.

If I have to clean out the tubes I just punch a hole in the screen and clean out the tube with the tube in place on the carb and then use a screen or gas tank filter sock over the end of the tube tied in place with a copper wire.
It's quite common for the long tube to severely clog internally due to corrosion if it's a brass tube.
 

Auto Doc's

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I am working on a briggs tiller model 130297 type 301501 code 88090207 and I replaced the tank gasket and the diaphram and it will idle fine when I adjust the needle valve but when I try to speed it up it stalls. I made sure the long tube was clear and I cleaned the hole in the side of the part that goes in the fuel pick up are. If I move the throttle slow toward high speed it will pick up speed for 2 seconds then stall. If I turn the needle valve out it will pick up speed if I move the throttle and sometines stay running but it won't idle smooth.
Hello T.,

This likely has a bad pulse diaphragm in the side or parts were not put back correctly.

Here is an aftermarket carburetor that is compatible:

 
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