B&S 5HP rebuilt carb, won't start again
#1
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I have an MTD chipper/shredder with a Briggs & Stratton 5HP engine (135212 Type 0272-01). Had not been taken care of, so I installed a carb kit, new plug air filter & pre-cleaner and used the chipper for about 3 days (probably an hour each day). Yesterday, the engine started 'hunting' ... I would fiddle with the Choke/Run switch and the idle speed and it never cut off, but was not running strong either. I finally stopped it to empty the bag and now it won't restart. Thought there might be a block in the fuel line, so tried ether but it still doesn't kick over.
Any suggestions?
Any suggestions?
#3
Did you clean out the rust and debris in fuel tank ? I would also install an inline fuel filter. Agree to check woodruff key on flywheel Then sounds like youll have to go back and re-do what you just did more thoroughly.
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Blocked fuel line? What fuel line? 
The “hunting” tells me you have a fuel passage restriction. The not firing using ether tells me ignition problem. Symptoms you describe are a bit confusing.
Check for spark and if you have spark, place some gas in the carburetor and see if it will fire off. If it does not you may have a flywheel key sheared throwing timing off.
If the engine does fire, the carburetor pick-up tube may have picked up some trash from the fuel tank or the carburetor was not cleaned well enough. Remove carburetor from fuel tank and remove idle mixture screw and fuel pump diaphragm. Spray all passages with carburetor cleaner and blow out with compressed air.
Here is a neat link that shows the operation of your carburetor. Look Mom, no fuel line!
http://www.bcot1.com/karting/briggscarb2.swf

The “hunting” tells me you have a fuel passage restriction. The not firing using ether tells me ignition problem. Symptoms you describe are a bit confusing.
Check for spark and if you have spark, place some gas in the carburetor and see if it will fire off. If it does not you may have a flywheel key sheared throwing timing off.
If the engine does fire, the carburetor pick-up tube may have picked up some trash from the fuel tank or the carburetor was not cleaned well enough. Remove carburetor from fuel tank and remove idle mixture screw and fuel pump diaphragm. Spray all passages with carburetor cleaner and blow out with compressed air.
Here is a neat link that shows the operation of your carburetor. Look Mom, no fuel line!
http://www.bcot1.com/karting/briggscarb2.swf
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Not sure I'm qualified to remove the flywheel (and from web browsing, it looks like I need a flywheel clutch tool, which I don't have), so I'll try cleaning the fuel tank. Is there a particular type of fuel filter I should install? Not sure where I can fit it, since the fuel line is metal, and runs below the exhaust.
When I re-clean the carb, I assume I can reuse the seal and gasket? or should I purchase another carb kit?
Thanks
When I re-clean the carb, I assume I can reuse the seal and gasket? or should I purchase another carb kit?
Thanks
#6
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What are you looking at that you think is a gas line? There is NO gas line on this engine. The carb sits on the gas tank and draws gas directly from the tank into the carb. No gas line. The filter is on the end of the pick up tube on the carb.
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It is impossible to install a fuel filter if the engine model and code you gave is correct.
Yes, you can reuse the parts you previously installed.
This is the simplest carburetor to clean there is. Use the most inexpensive (cheap) aerosol carburetor cleaner you can find. Spray through all holes and the tube. Spray in the fuel tank. Is the tank rusty or have old fuel buildup? If it does, the fuel tank needs to be cleaned.
Yes, you can reuse the parts you previously installed.
This is the simplest carburetor to clean there is. Use the most inexpensive (cheap) aerosol carburetor cleaner you can find. Spray through all holes and the tube. Spray in the fuel tank. Is the tank rusty or have old fuel buildup? If it does, the fuel tank needs to be cleaned.
#8
Get one of your buddies place a large screwdriver between the block and flywheel in such a way as not to break anything, then directly opposite of the screw driver place another one. Install flywheel nut flush to end of crankshaft. gently pry up on screw drivers and tap the end of the crankshaft. This has never failed me yet when Ive had no access to my tools.
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I took the carb apart and cleaned everything again. The fuel tank looked very rusty on the inside, so I swapped it with another identical fuel tank and the engine restarted the first time. So, it must have been dirt somewhere in the system. Two follow-up questions:
1) What is the tube (that looks like a fuel line)? It comes off the engine block and goes into the back of the carb. Indypower was right in that it's not a fuel line because it does not attach to the tank, but simply goes across the top of it.
2) Since there is no place to attach a fuel filter are there any other options for keeping dirt out of the system? The intake that slips inside the fuel tank has a screen on it, but it is dirty and a little rusted. Can that intake be replaced, or does the whole carburetor assembly have to be replaced?
Glad I didn't have to mess with the flywheel!
1) What is the tube (that looks like a fuel line)? It comes off the engine block and goes into the back of the carb. Indypower was right in that it's not a fuel line because it does not attach to the tank, but simply goes across the top of it.
2) Since there is no place to attach a fuel filter are there any other options for keeping dirt out of the system? The intake that slips inside the fuel tank has a screen on it, but it is dirty and a little rusted. Can that intake be replaced, or does the whole carburetor assembly have to be replaced?
Glad I didn't have to mess with the flywheel!

#10
The tube you describe is a crankcase breather tube, it simply pulls gases from the crankcase thru the carb and reburns them like a pcv system on an automobile engine. Use a funnel with a screen in it that will keep out small dirt particles. Yes, you can replace the pick up tube, only a buck280 at your local briggs dealer. It just twists out and twists in. Hopefully youll never have to tear into this critter again. Also remember to drain float bowl of gas when storing for long periods. Some folks use stabil in their fuel tanks but I prefer to drain the gas and blow the tank out with compressed air .