clogged fuel filter in line or gas cap that is clogged and not letting air in.

From your description, I would suspect the fuel hoses. The one coming out of just left of center of the crankcase and running to the fuel pump is a vacuum line operating the pump. If it is leaking air, no fuel will be pumped.

Could also be fuel pump, crap in carb., carb float needle could be stuck closed. A sharp rap on the side of the bowl might dislodge it IF that is the problem.

Walt Conner

You may just try removing the air filter and spit cap and spraying a shot or 2 of carb spray down the carb venturi and attempt a start up. It's like a mild starting fluid. Maybe after it runs for a few seconds it will pump away and run well. Obviously, any signs of leaks or if the lines are cracked deep- they should be replaced. The lower l/h side of the carb has a hex bowl drain ( 5/8 or 3/4)where you can drain some of the old stuff out and take the straw from the carb cleaner and get a bit more out and clean the jet. Worse than that , the top has to come off the carb and be cleaned.

Walt nailed this one.

On some of the Craftsman mowers with opposed Twin engines, the fuel line between the carburetor and the in line fuel filter frequently developed cracks. As you crank the engine the fuel pump is drawing air through the cracks in the line. You can verify this by disconnecting the fuel filter and installing a vacuum gauge. As mentioned, it would be a good idea to install clamps on the vacuum line from the crankcase fitting to the fuel pump.

I am having similar prblems with my 20hp Briggs. Poured fuel in the carb got it to start and then appeared to be running for a short time (1 min). Then stopped and can't get it to go again. The fuel lines do not look too bad any one have any more ideas?

I see you are running another thread on this. Might try hooking up a temporary gravity feed gas tank. If it runs now then the fuel pump isn't working. I think in the other thread someone mentioned about the solenoid shutoff. If it is equiped with this it will be a nickel size canister about 1" long sticking out the base of the carb at the lower right side as you look at carb side of engine. This must have power to it and must open.

Walt Conner

Walt, I removed a solenoid once and turned on the key and it rapidly pulsated from open to closed. Is that normal operation?

I will try to set something up with the gravity feed, thanks. I suspect this is my problem...When I cracked the bolt on the side of the carb (jet behind) no fuel came out...My confusion is all I did was disconect the whole intake from the system when I replaced pistons, etc. Why now am I having a fuel problem never that I never had before. I disconnected the vaccum line and cranked over manually. I felt nothing on the end of the tube (suction or pressure); should I? I did take the fuel pump off, the spring and guide are against the bladder and fit in the carb hole...I am at a lose for what to try next.

"Walt, I removed a solenoid once and turned on the key and it rapidly pulsated from open to closed. Is that normal operation?"

No. It should stay open when current is applied, close when disconnected.

"My confusion is all I did was disconect the whole intake from the system when I replaced pistons, etc. Why now am I having a fuel problem never that I never had before."

I suspect that you connected the hoses wrong. The vacuum hose from the engine block connects to the BOTTOM of the fuel pump. The line from the gas tank connects to the left side of the fuel pump.

Walt Conner

Walt, I work in the fuel oil business and the newer oil pumps use a coil the open and close the fuel valve. They energize and hold the valve open, but never pulsate.

The model in question was a no-start Honda tractor. It had been driven 5 miles to a house and worked flawlessly. Then it wouldn't start the next day. I removed the solenoid and it pulsated rapidly after I pressed on it with my finger. My guess was that the solenoid had stuck. But I wasn't sure if the pulsating was normal. It has worked for the last few weeks.

Honda solenoid operate the same way???

Walt...Let me confirm...the vaccum line connects to the brass nipple that is pressed into the carb (aluminum) and the fuel line connects to the plastic nipple on the side.

"brass nipple that is pressed into the carb (aluminum) "

The fuel pump on these engine is a rectangular block attached directly to the part of the carb facing you. The vacuum line attaches to the bottom of this rectangle, material may vary, the gass line connects to the left side when facing carb side.

Walt Conner

Walt...Thanks for the help, I got the thing running finally it took it a while must of had to prime the carb but it ran...So I spent about 2 hrs adjusting the governor through trial and error and it seems OK but I am not sure it is quite right yet. I saw you had posted some instructions on other threads and thought you might be able to help. Here is what I did...
1. First adjusted the idle adjustment for idle condition.
2. Set throttle cable position based on the idle position allowin gthe "cam bracket" to interface with the governor arm pin.
3. Now the fun part...Throttle full on, I rotated the governor arm (into block) counter clockwise and rotated the linkage arm clockwise and locked into place.

Again, this seemed to provide the best results but just not quite right. Any help would be appreciated. The modle is a 461707-0143 20hp opposed Briggs.

Turn Governor shaft counter clockwise and re-tighten clamp while holding throttle wide open is correct.

Unfortunately this model has some trouble running right due to the lean burn requirements of EPA. IF it is not running steady, you might try removing the top of the carb. Be VERY careful with the gasket. It has to come off with the top and will be hard to find if damaged most likely requiring buying a carb overhaul kit to get it.

Clean out any crap in the bottom of the carb bowl. Blow compressed air into all orifices in the top of the casting especially the one that is brass. Re-assemble.

Good luck.

Walt Conner