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Hot!8 hp Briggs flathead runs poorly with new parts

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2017/07/04 11:13:02 (permalink)

8 hp Briggs flathead runs poorly with new parts

My BCS shredder engine is 16 years old and time for new carb, so on it went, started first pull(!) and seem to run and idle okay, but old fuel lines leaked. New lines went on, but then wouldn't start, so I figured I had hooked up the fuel pump wrong (didn't mark lines, first mistake). Should have looked at an online drawing but took off pump cover (second mistake) very carefully and didn't see two little springs fall out. Sigh (actually, I went to a very dark place cuz I know better but got sloppy). Fair enough, it was old and the rubber in it probably wasn't in good shape, so new and different style then original replacement was called out when I ordered from Jack's. Oh goody, all new parts and a clean-as-a-whistle fuel tank and it should run like a banshee. 
Hard to start without starter fluid, runs only on full choke and roughly, open choke and dies. Opened carb to find it sparkling clean and main jet clear. Plug good. New air filter, btw. Not getting enough fuel. Disconnected pump to carb line and pulled cord, pumps fuel in spurts. Tank 3/4 full, I ran fuel line straight to carb, still won't run right. 
Does this carb need pressure from a pump to run? Would gravity fuel delivery suffice in order to rule out bad carb or pump? Is fuel pump perhaps mismatched even though it was listed as replacement? 

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    Re: 8 hp Briggs flathead runs poorly with new parts 2017/07/05 17:10:25 (permalink)
    You should be able to gravity feed the carb to test it out. Most of those fuel pumps have low pressure because if it is high it would flood carb. Most carbs I have seen, forcing float valve/needle off seat with 5-7 psi.
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    Re: 8 hp Briggs flathead runs poorly with new parts 2017/11/26 12:57:37 (permalink)
    See if you have fuel in the bowl. It is possible something got into this part of the system.
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