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Putting a Mercury 5HP back to life

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beckerjs

Outstanding Contributor
"pull the float out and bend t

"pull the float out and bend the tab, shake it first to see if its got a leak. MOB switch just grounds the ign out same as the kill switch. Should be a black/yellow wire, when grounded the engine won't start"
 
"Thanks! The float has no leak

"Thanks! The float has no leak. Is there a setting for the float? I have adjusted a couple of times now (bending the tab), but no succes yet. It keeps spitting out gas."
 
"I believe level with the body

"I believe level with the body. Look at the needle and seat, might be worn or a piece of crud built up on the inside from sitting. You can place a clean hose on the carb and blow into the line working the float/needle to see if it seals. I have no real setting for the float other than the norm"
 
"I have got the float parallel

"I have got the float parallel with the body. I have checked the needle and seat, these are clean and in good condition. It seems to seal when I blow into it. Still it cuts out after about 10 seconds now. At the moment it cuts out it starts spitting gas through the suction end of the carb. When I check the spark plug after this happens it is wet."
 
"now thats different from a st

"now thats different from a stuck float. first cutting out could be lack of fuel, clogged main jet in carb, fuel pump failure, or anything electrical. Spitting out the carb is ussually bad reed valve or running extreamly lean, which causes sneezing.
Lets rule out the float, pump bulb with engine off, look down throat of carb, if no fuel is dripping/pouring out then the float is not flooding the carb.
Sneezing and spitting, does it rev up or is it just barely running? Must clean the main jet, follow the brass screw in the middle of your picture, blow it clean, remove it if you must. Make sure air or fuel flows from there through the center of carb. Trace it with some small speaker wire if you have too. The idle jets must be cleaned the same way. Screw the idle mixture screw in until its lightly seated, count the turns, remove it. Clean the ports all the way to the back of the throttle butterfly verifing air passes out each small hole. Reinstall
To check fuel pump, squeeze fuel bulb while running to see if it cures the problem."
 
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