Mower starts after priming, then quits. new sparkplug, air filter etc. cleaned bowl still no luck. cleaned out orifices in bowl screw. nothing. Suggestions?

It runs on a prime so that eliminates an ignition problem and indicates a fuel problem. You are on the right track, you just missed something in the carb. Remove the carb and clean it again. Be sure all passages are clear. you mmentioned that you replaced the inlet needle- what about the seat? They come as a set and should be replaced together. Be sure you clean the passages in the fixed jet also.
Take your time, clean the carb thouroughly and your problem should be solved.

Remove air cleaner and replace filter. Spray carb cleaner in choke at choke flapper. Remove carb float bowl and clean. check float bowl screw for hole thru it, clean out with thin wire if present, reattach bowl and screw, ensure gasket on top of bowl is good, Have mower model no. get new bowl gasket kit at mower repair store.

Try looking at the screw that holds the bowl in place, sometimes they have a little orifice on them that gets clogged and hinder fuel from reaching carb. Use a small pin or small gauge wire to clean. Good Luck...

First thing I would check is the air filter. Then the belt that drives the wheels. Open up the belt area and clean. Last I would check the carb. Good luck...Lee

Fuel Starvation - Float Bowl Carburetor
1) remove air filter assembly
*be cautious of tearing the mounting gasket. If it does tear, you HAVE to replace it. It is part of the priming system
2) remove the float bowl fastener. This is the main jet
3) carefully remove the float bowl, the rubber o-ring/gasket will not be able to be used if it is removed, you WILL have to replace it
4) using a spray 'carb cleaner'
spray up thru the center of the carburetor
spray and clean the main jet with cleaner and 'tag' wire
(tag wire is very thin, and can be used to clean the hole in the center of the main jet)
5) clean any debris from inside the bowl or carb body
6) re-install bowl and center bolt, air filter assembly

*if you need gaskets, your Briggs dealer can supply. The kit is cheaper than individual gaskets, and all the parts needed to finish the above repair are in the kit.

I’m happy to assist further over the phone at https://www.6ya.com/expert/rolandw_c013176d62ee17ae

I have a Sears Craftsman Vacuum/blower with a 4.5 Tecumseh that wouldn't start. I removed the screw on the bottom of the float bowl and cleaned both the bowl and the screw. The screw has two small holes on each side which feed gas through the middle of the screw up into the carb. There was gunk which had clogged the holes and therefore no gas was getting to the carb. Once cleaned and reattached, the engine ran fine. Unfortunately, I also took the air filter housing off the carb and one of the two screws stripped while putting it back in. Be careful when threading any screws.

Ok here are 2 possible solutions.
1. If you have a mower with a sediment bowl under the carb and flat paper air filter, try this. Drain gas from gas tank. Remove the screw that holds the air filter cover. Replace air filter is dirty. Remove the two or three screws that are holding the flat plastic back of air filter cover. Remove the little gasket that is between the flat plastic back and sediment bowl. Make sure you remove all of old gasket. Clean the area around the sediment bowl so it is free of dirt and grim. Use a 1/2 socket (usually) and remove the bolt on underside of the bulb. The remaining gas in the bowl and a little left in the tank will leak out. I let it all run out so if any water is in tank it emptys on its own. Remove the bowl and clean it out with clean rag or paper towel. Use some carb and choke cleaner to spray the carb. Reattach the bowl, and tighten the bolt making sure the ruber gasket between the bowl and carb is not twisted or you will have leaks. Install a new gasket between carb and air filter back replace 2 or 3 screws and air filter and cover. Refill with gas, prime it and then try and start it.

2. If your carb is located ontop of the fuel tank, remove the cross tip screws that hold carb to tank and get a new diaphram (fuel pump in a sense). Replace diaphram and reassemble in reverse. You will have to also remove the bolt that holds tank to motor and the little metal rod that goes from the govonor to the choke.

From what you stated I would think it is number 1.

Good luck. Let me know if this helps.

roundo4

if you are getting no fuel to the plug you either have a stuck float, plugged fuel line or filter. does the gas reach the carb bowl? does the mower have a fuel pump? if so the diaphram might be bad.

carb is gummed up. carb cleaner is the only thing that will help, Get it at walmart, spray can usually less than $3. Comes with a wand (straw) for spraying in small holes etc. Take the air filter off and look for small holes around inside the carb intake, stick the straw right in those and shoot, WEAR goggles or classes and rubber gloves, stuff is nasty. If it still won't run you will need to do some disassemble of the carb, if it has a bowl remove it and wash everything out with the cleaner.DO NOT however get the carb cleaner on the bowls top rubber ring it will wreck it. Be careful to put the float and needle and seat back as they were. The brass screw that holds the bowl on has some tiny cross holes in it, one strand from a wire brush works great for cleaning them out. Good Luck, Chuck

this is a very common problem with these toro mowers. the needle valve in the bowl of the carb. is plugged up with dirt or varnish from the fuel. just under the primer bulb there is the carb bowl. it has a nut under it that holds it on remove the bowl and make sure fuel flows constantly while the bowl is off. push up on the float to stop the gas flow. this could be messy and dangerous. careful with the gas. its flammable. best solution is to remove the carb and soak it overnight in a parts cleaner like gunk. caution small parts inside. this happins every year on mine no matter what i do. seems like the orifice is so small it clogs easily. good luck