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B&S engine #128M020943 6.5 hp. I was mowing and stopped to clean out bag. When I tried to restart it would not start. Since then I have replaced the magneto after r bench testing and it only had 6.50 ohms. Then I removed the carb and completely cleaned it, including running g a wire through the jet all three holes. The center jet only has a hole about the size of a straight pin. After doing all of this I am getting plenty of s park
But I a m not getting fuel delivery. I am stumped.

Today's Briggs magnetos cannot be tested, as we could do with the old points/condenser systems. The ohms test you did means nothing. That being said I'll bet that the float level is too low, due to a swollen seat. I would be cleaning the carb and replacing the float needle and seat. Here is the procedure I use.

Needle and seat replacement.

Remove the carb, and then remove the float bowl. Check the float bowl jet (which is the bowl screw) and make sure the jets both horizontal and vertical are clean and open. Tip the carb upside down and remove the float pin and float with needle attached. Look in the float needle passage and you should see the red float seat at the bottom of the passage. This is where a #5 crotchet hook would come in handy as you need to remove this seat. If you have no hook, but compressed air, you can blow through the fuel inlet and try to pop the seat out. Put your thumb over the passage to prevent the seat from flying who knows where. No air or hook try bending a stiff paper clip to dig the seat out.

I would either give the carb a good 24 hour soaking or have it ultrasonically cleaned at this time.

With the seat out clean the passage way with carb cleaner. Now you must find a drill bit slightly smaller than the passage way, to be used to press in the new seat. Apply a very, very small amount of a very light lube to the new seat. 3-1 oil or lighter, to help seat it better. Carefully insert the new seat in the passage way with the rings on the seat down toward the carb body. Slowly and carefully force the seat down with the back end of the drill bit. Once it is seated, check to see that it did not flip and the rings are up. *Next check to make sure that the float does not have any liquid in it. *If it does, replace. *If everything looks correct, attach the new needle to the float and install with the float pin centered. It everything is correct, the float should seat level to the carb body, when looking at it upside down. If everything looks good reattach the float bowl, making sure that both the bowl gasket and the nut gasket seal properly. Reinstall on the engine and test unit. Remember to have patience and take your time. Good luck, but I don't think you'll need it.

PS: *On the side of some Tecumseh carbs you will find a plastic cover. *Under this cover will be an idle jet. *Remove it and check to see that the jet is open both horizontally and vertically. *You should be able to push the old float needle wire through the vertical opening.

I will try it and post the results.

I replaced the needle and seat and removed an Inline filter I had placed in the line. I tried to start with no result. I sprayed starting fluid in the cylinder and it turned over maybe 4 or 5 revolutions and bleached out the exhaust.

I'm assuming you cleaned the carb and set the float level as I posted. Did you check to see if fuel was coming out the nozzle when you pushed the primer? If you have enough fuel in the float bowl and the engine is priming, the next thing I would check is old fuel.

This is a self priming model that uses the heat coil to control the butterfly.

The carb has been cleaned and after cleaning I put the float in water and it floated.

Sorry I punched in the wrong engine type. Again did you check the float level as I said in my procedure. This is critical to getting fuel in the cylinder.

It has a plastic float and there is no float adjustment

Sorry, I guess I can't help. Your assumptions and not wanting to follow my procedure leave me no option than to back out of this thread. The float can be adjusted, if you understood my directions and how a carb works. Hope someone else can help you or you can just purchase a new carb. Good Luck.

So is the choke on at cold position? If the air vane is not adjusted right then it will not start. Have you attached the little spring back on? The thermostat under the engine cover could be sticky or seized and not allow choke on.

Also use fresh fuel.

You could manually push vane with hand at different choke positions and get somebody to pull engine starter to see if it fires.

You replaced the magneto. Have you adjusted the magneto to flywheel magnets with a business card?
What are you using to check spark? You should use a spark tester.
Also metal plug caps can cause a non spark issue but usually allow cold start and when warmed up they breakdown electrically and cause a bad hot start.
Depending on model type and code depends on what plug and what gap should be.

Yes I checked with a spark tester,I have a brand new plug ,I set the magneto with a business card. I have a needle and seat and the float is plastic and I don't see how I can adjust it because there is no tab as on the old brass floats.

Also it is a non priming engine with a heat coil to open the butterfly located behind the exhaust.

How would the engine act if their were teeth missing on the camshaft.

Rgflo64 said:

I replaced the needle and seat and removed an Inline filter I had placed in the line. I tried to start with no result. I sprayed starting fluid in the cylinder and it turned over maybe 4 or 5 revolutions and bleached out the exhaust.

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Does it start if you spray starting fluid into carb? Does carb bowl have fuel in it?

No , it makes a few revolutions and puffs out the exhaust.

I pulled the cylinder head and turned the engine manually and I have the intake partially open on the power stroke and the exhaust valve not opening until the end of the exhaust stroke. It appareny somehow.jumped time.

Check the flywheel key to see if it is sheared which would normally be done by blade hitting something hard.

Remove flywheel nut and cup to see.

The flywheel key is good, looks like new. The reason I pulled the head was the engine would not start but it would puff out the exhaust.

Rivets said:

Sorry, I guess I can't help. Your assumptions and not wanting to follow my procedure leave me no option than to back out of this thread. The float can be adjusted, if you understood my directions and how a carb works. Hope someone else can help you or you can just purchase a new carb. Good Luck.

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Thanks,for your input, but my problem was not with fuel after all, it turns out for some reason the engine jumped time and after further investigation I split the case and found the nylon camshaft was missing 2 teeth. I installed a new camshaft and it started on the first pull and runs fine. I just needed to look deeper.