Gas started blowing out the back of the air filter...I noticed the hose connects to a valve that appears loose (spins) is that my issue?

Tracking down fuel problems.

NOTE:The MTD Yard machine Model 13AO772H755, Briggs 15.5 hp engine does not have a fuel pump.Ignore all references to the fuel pump.However the rest of the fuel pathway should be checked just the same.Watch the video.

1. Make sure there is plenty of fresh fuel in tank. High Octane less than one month old. Water in the fuel system will often cause hard starting, low power, backfiring, surging or stalling
   
2. Is there a cut off valve at the gas tank? If so check that it is open or working if it is electric.
   
3. This step comes from repeated personal experience with JD gas tanks. Remove fuel line from filter and remove the filter, gas should pour out of the hose coming from the tank. (look at the filter before removing it, it should look at least 1/2 full of fuel.) If gas does not pour out remove gas tank cap. If fuel flows now, you need to unclog the cap vent or replace the cap. The vent is that tinnnny little hole in the center of the cap. If the fuel still does not flow then blow air from the filter end of the hose back up through fuel line to blow out any blockage inside the gas tank.
   
4. Consider my own experience when my engine to quit in the middle of a mowing job: I was mowing along on my LA145 (200 hours on it) when it slowed down and died. Before it died, it acted like it was losing power. It thought it was only firing on one cylinder. I waited about 20 minutes and it restarted after a lot of cranking and some priming. I made a couple more mowing passes; the same thing happened again.
   
   I knew this mower was in top running condition. There were no engine misses, no backfires. It was not abnormally hard to start. The carburetor was clean, the coils were good, the plugs and fuel filter were recently changed. Lifting the hood, I noticed the fuel filter was nearly empty. It should be ½ full, or more. I pulled the hose off the tank side of the fuel pump and saw there was no fuel flow.
   
   Gas should gravity flow from the tank to the fuel pump, if the tank has a good supply of fuel. I wiped the hose off and blew air back into the fuel tank. It helps to take the gas tank lid off first. After I got a good flow of air going back into the tank (you can hear the bubbles) the fuel began to gravity flow back through the hose at a decent clip. This fixed the problem. There is likely silt build up in the tank and it settles at the output port blocking the flow of fuel.
   
   The problem repeated itself several times last summer. Back at the shop, I used compressed air (turned down to 20 psi) to blow the line clear. The problem reoccurred this spring. I used the same method to clear the line.
   
5. Do your self a favor, leave the gas cap off and turn the outlet air on your compressor down below 20 psi. If the tank is nearly full you will blow gas out of the tank. Do this outside if possible; at the very least you need a well ventilated area. After blowing air from the air filter back to the tank, you may have to reverse the process and pressurize the tank to get the fuel started. I place my hand over the open tank and hold the air hose between the joint of my thumb and forefinger to seal the tank, and then squeeze the trigger. Once you have a good fuel flow out the line to the filter, put on a FRESH FILTER. Try cranking the engine. If it still does not start move on to the fuel pump and carburetor
   
6. Check the fuel pump. The fuel pump system on the twin Koehler and the Twin Briggs (and others) are almost identical. Watch this excellent, eight minute, video to learn how to check the fuel system, including the pump, up to the carburetor. . Small Engine Repair Checking Vacuum Fuel Pump Fuel System on Kohler Twin...
   
7. Note: My engine was starting hard and dying in the field this year (March 2015). While doing a valve adjustment, I found a hairline crack in the bend of the vacuum hose powering the fuel pump. It's the short hose running from the valve cover to the fuel pump. The fuel pump will not work if this hose is cracked.
   
8. Many systems have a fuel shut off solenoid. This is a small cylinder on the bottom of the carburetor. It has two wires running to it. It should make an audible click when you turn the key on. If it does not click you will have to replace it or track down an electrical problem.
   
9. If this has not solved the problem you may have to remove and disassemble, clean, or rebuild the carburetor at this point. You may have water, dried fuel (varnish) or trash in the carburetor bowl. Before removing and disassembling the carburetor try draining the bowl. Or, take the bowl off, careful not to drop the small parts inside. Clean the bowl and replace. I often remove the bowl on small engines and save the hassle of a complete carb removal.

NOTE: Connect a volt meter across the two battery posts. If battery voltage drops below 9 volts when cranking or while the engine is running, the fuel cut off solenoid will not function. That means the engine will not start or will die soon after starting. So check your battery voltage before, during, and after cranking. If the battery voltage is good before but drops below 9 volts while cranking this is generally a sign the battery has one or more bad cells. Replace the battery. If the battery is in fact good, and the voltage is still dropping, you may have a bad starter motor which is drawing too much amperage.

If you find this fuel checkup does not solve the problem, repost your question with updated info and I will walk you through the next step. Tracking down a spark problem; yes, your problem could involve the coil or any part of the ignition/spark system. (Not as likely as fuel)
Small Engine Repair Checking Vacuum Fuel Pump Fuel System on Kohler Twin...

change fuel filter also air

Check for a fuel shutoff valve in the fuel line. Many manufacturers have them to allow the users to run the carburetors empty at the end of the mowing season. It is easy to forget about.

code p 0442 refers to evaporative emissions(EVAP) system---small leak detected ===causes ---hose connections ---intake leak---EVAP canister---EVAP cannister purge valve
it also refers to mechanical fault --hose connections --EVAP pressure sensor

Okay I got tired of this and did something about it . so here is the solution . Pull off the bed . 6 bolts , hit them with a 2 pound sledge hammer and use a impact or a big 1/2 drive . Disconnect tail light harness on drivers side just above bumper area. undo screws on gas tank filler . two people can lift off bed . on top of the spare tire you will see the charcoal canister . About a foot long and black with a solenoid on the drivers side .connected to this solenoid by a cigar sized hose is a black box with another hose on the other side . This is a air filter . Lets in air when the solenoid opens so the fumes can travel back up the line . Notice that the open end hose is just right for collecting all the dirt and water that flies up there . This canister as it is marked has some foam inside like a lawn mower air filter . either go buy another at the dealer or simply tap it on the truck frame and get all the dirt out and blow out with air hose would be good if it is wet inside . Blow in it to make sure air flows freely through it . Put it back on .

Okay if that just happens to not be it here is how you find out what is it . After removing the bed make sure the vents on top of the gas tank are not plugged by blowing and sucking on them . Then unhook the fume line from the solenoid on the charcoal canister . Drive , I know no lights for breaks , to gas station and start filling up . If it splashes out then it is on the tank side . If not then plug up the line you removed and fill. If it splashes out then it is after the solenoid . Put thumb over other end of solenoid where the air filter is attached after removing the filter hose of course . If it splashes out then it is the air filter .
Make sure you point that hose on the end of the air filter at a downward angle so it does not collect water and dirt again . Stupid Ford makers .

Process of elimination.

I am so glad I can now fill my tank . Why in the he## can not all these mechanics on all these forums come up with the answer ? Or even the dealership.

As fuel level rises in your carb, the floats press upwards on a little brass valve that has a tiny rubber tip. This seats into a perfectly matching valve seat that stops incoming flow from tank to carb when fuel height is correct. trash in the seat, improper fuel float height setting or a damaged tip will cause the fuel to over fill the bowl and drain all over your garage floor. My advice before making any height adjustments is to thoroughly clean your carb with compressed air. If it has a hole that you can put air in, do it. Include the fuel inlet port in this. blow out venturi and clean the inside of your intake and filter housing. With the bowl removed, blow air into the fuel inlet with your mouth while slowly pushing up on the floats. a little after the floats reach horizontal, you should notice that you can no longer blow air in. If you still can even with the floats pushed all the way up, your valve tip is damaged. Remove float and inspect valve seat (inside the hole) and valve tip.

Check the air cleaner and muffler for plugging. Remove the carburetor, open the lower chamber and check the diaphragm for any holes or cracking. Also check the small fuel control valve that the diaphragm controls--either can cause flooding if not working properly. Hope this helps!

Hello,
your problem appears to be the idle control motor located on the air intake manifold it is a small motor that goes bad quite often. Other items that can cause this is a bad /clogged air filter or a tune up (spark plugs and wires), or clogged fuel injectors. to clean the injectors you can buy a container of fuel system cleaner and pour it into the gas tank and as you drive it cleans the system.

Once the fuel system is cleaned via a tankful of cleaner & gas then the idle controller motor would be next on the list to be replaced.

Good Luck !
Rich Lilja

Inspect Wireset Damaged, worn, or deteriorating spark plug or coil wire(s). in this list u will find a answer to ur problem Shaun 2 Inspect Spark Plug Fouled, damaged or broken spark plug(s). 3 Inspect Fuel Filter Clogged or dirty fuel filter 4 Inspect Distributor Worn, loose or incorrectly adjusted distributor. 5 Inspect Distributor Cap Loose or cracked distributor cap 6 Inspect Distributor Cap And Rotor Kit Loose, cracked, or worn distributor cap and ignition rotor. 7 Inspect PCV Valve Plugged or damaged pcv valve. 8 Inspect Air Filter Restricted or clogged air filter. 9 Inspect Catalytic Converter Clogged, damaged, defective or faulty catalytic converter. 10 Inspect Automatic Transmission Improperly adjusted kickdown cable adjustment or internal transmission problems. 11 Inspect Fuel Pump Improperly functioning fuel pump or circuits. 12 Inspect MAP Sensor Improperly connected or faulty m.a.p. sensor. 13 Inspect Mass Air Flow Sensor Improperly connected or faulty mass air flow sensor. 14 Inspect Throttle Position Sensor Faulty throttle position sensor or throttle position sensor circuit. 15 Inspect Timing Specification Incorrectly adjusted engine timing. 16 Inspect Fuel System Pressure Incorrect fuel pressure being delivered to carburetor or fuel injection system.