B&S questions

#1
Picked this up 10 years ago, it started with starting fluid and sounds good but I think I need to rebuild the carb it would not stay running. Is a 494624 the correct carb kit? Where is a good place to get a complete kit? Also what is the year of this motor and is it electronic ign? Also the throttle is all the way open so I think the governor spring is not right. Thanks for any help!
 

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Harquebus

Well-Known Member
#3
I'd disassemble the carburetor and clean it but the most likely culprit is the diaphragm on the left side/exhaust side of the carb (it's the plate with 4 screws). Replace that first and see if it works. Then, stay away (as much as you can) from ethanol blended fuels (10% ethanol, etc) and try to use 100% gasoline in this engine as that fuel will be much, much kinder to the diaphragm material than fuel with corn squeezin's in it.

In fact you can buy Briggs diaphragm kits that include just the diaphragm, the spring and the spring cap.

That looks like the right kit based on internet photos, but be sure you can see what you are getting before buying and don't be dismayed that you see lots of parts in the kit that don't fit your application--the idea there is "one kit fits many" and more is more.

I'd buy from ebay (or Amazon) as I've found the absolute most rock bottom prices there (why pay more?).
 

Bird Brain

Active Member
#4
Might also check the bottom screen on the 2 pick up tubes that go down into the tank. They do varnish over or get trapped with rust and become blocked at times. That will require removing the tank from the carb although. Maybe a shot or two or carb cleaner to the bottom of them. And clean the small second resevoir out for the short tube while its apart. They hold water once it gets in them. Best of luck.
 

Lizardking

Well-Known Member
#5
The long pick up tube was loose on mine and wouldn't run in WOT. The screens had varnish too. I just tapped the tube back on the carb with a plastic screwdriver handle. I cleaned the carb and checked the diaphragm and now runs great. Check for any cracks on the pick up tubes that might be letting air in.
 
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Harquebus

Well-Known Member
#6
What these two guys said. ^ ^

Might as well take it ALL apart, do a deep clean with carburetor cleaner, an ultrasonic dip, poking the jets with thin brass or copper wire strands and when you replace the tank-to-carb gaskets it might require two, stacked, for a proper seal. The carb base has a tendency to warp with age and a straight bastard file drawn across the base alternating the angles, being careful to file around the fuel pickups, can get you close to flat again. The top of the steel gas tank is also not a precision surface and it can warp too or be dented or rippled from a hard service life. . . . .

Good advice on the fuel pickups. I've replaced the lower screen before with OEM parts but I bet you could get by with removing the clogged screen just leaving it as a bare pickup tube or even wrapping the end with fine mesh screen and fastening it to the tube with wire. The beauty of the old Briggs Pulsa-Jet, adjustable jet carbs is that they filter the fuel twice.
 

Harquebus

Well-Known Member
#7
Nearly forgot your other question. With a date code of 1986 your engine should have the solid-state Magnetron electronic ignition armature which replaced the old armature, points and condenser.

*That is assuming the blower cover is original to the engine but I have my suspicions; your fuel tank already doesn't match so what else is incorrect on your motor? It could be a replacement blower cover and your engine could be much older so you might have to check. Magnetron was introduced in 1982 according to wikipedia (not always reliable) although I am seeing claims that it appeared on engines that were built after August 1, 1981.

The easiest way to tell if your engine has points and condenser ignition is to remove the blower cover shroud (3 screws: top, bottom L, bottom R) and look for wires that go under the flywheel. Magnetron ignition has only one wire and it is routed to the outside to serve as the kill switch.
 
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