New to the form just signed up today. I have a Briggs & Stratton 20 hp V- Twin Model # 407777-0268E1 Code 030102YG. The engine will start up a run fine (hot or cold). It starts to break down( popping through the exhaust) an miss about 60% throttle or when you engage the blades. It is not bad enough that I can not cut grass but I know it is not right. I have adjusted the valves, new plugs, air filter, fuel filter. The hose from the valve cover to fuel pump was bad replaced that also. Thought that was the problem but still popping through the exhaust. With engine running I can pull Left plug wire(oil filter side) off and there is no change to the Eng. pull right plug wire on Eng. it makes a big difference in running. PLEASE HELP.
Need help on B-S V-twin
- Thread starter Goober11
- Start date
Check for water in the gas. Also get a lighted spark tester and check for good spark. You problem maybe fuel related meaning water or time to clean the carb. After looking at your carb it's a double barrel carb prob not getting the proper amount of fuel at times or none at times.
Thanks for reply. Will check the items you talked about tomorrow it is 10:25 Friday night here. I did pull the top cover off an the flywheel was full of rust cleaned everything up. set gap in coils. Did run better but still not right. will look at carb. tomorrow . I can pull the choke out some when running and it does not help.
cpurvis
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If pulling the left plug wire makes no difference in the way the engine runs, then that cylinder is dead.
It could be something as simple as a bad spark plug or plug wire.
Or it could be a bad ignition coil.
Or worse, it could be a broken pushrod or a valve guide that has moved in the head.
It could be something as simple as a bad spark plug or plug wire.
Or it could be a bad ignition coil.
Or worse, it could be a broken pushrod or a valve guide that has moved in the head.
I think I have a dead cyl. also. I did take a compression test on it. Not sure how accurate it would be on that engine. Left was 100, right was 75. I do not have a spark tester but when I pull the plug wire off when the engine is running it will throw a good spark. I do not have a leak tester my have to pick one up to help me diagnose the problem. I am new on working on small engines. Worked as a mechanic for 45 years mostly on diesel road tractors. I am trying to learn about small engines to help me save some money and there are not to many shops around here that i would want to take it to. Sorry to say.
Boudreaux In Eunice La.
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Take the suspect head off and then check for the valves and pushrods..... No need to get into the whole engine.......
Let us Know Mon Ami ~!~!
Let us Know Mon Ami ~!~!
Tinkerer200
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I think he means to take to valve cover off first and check push rods, IF all is well there (doubt it is) then take the head off and check valves.
Walt Conner