Help! starts on muffs but not in the water???

further

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Please help!! 1988 force 85hp starts fine on muffs and runs good but when I put it in the water it doesn't start at all and the bulb won't stay hard. What could it be? Thanks in advance for the help. Diaphram is new, carbs rebuilt, new water pump, new plugs.
 

john from md

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Re: Help! starts on muffs but not in the water???

Did you ever replace all three check valves in the fuel pump?

John
 

further

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Re: Help! starts on muffs but not in the water???

no, just one, the easy one
 

further

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Re: Help! starts on muffs but not in the water???

would bad check valves cause the motor to start on muffs and not in the water?
 

john from md

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Re: Help! starts on muffs but not in the water???

Bad check valves allow a lock between the carb and the fuel pump which starves the carbs for fuel. Just replacing the center check valve isn't good enough.

John
 

further

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Re: Help! starts on muffs but not in the water???

yes, but it runs fine on muffs? is it due to the load of beinv in the water?
 

foodfisher

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Re: Help! starts on muffs but not in the water???

Being in water might create enough backpressure to stall a starving engine. Try a barrel and find out.
 

further

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Re: Help! starts on muffs but not in the water???

Update - so this morning the mechanic calls me and tells me that he put it in the water and it fired right up and went fine??? What the heck am i doing wrong - this is crazy!! So I went to the marina and we took it in the water and got it to plane pretty quick max 30 mph at about 4500 rpm same as I had before my carb rebuild project began. So great took it back to my lake put it in the water (about 45 minutes after taking it out) and had a real hard time getting her to start again. Finally got it and went out. So here's the weird part, my wife and kids got in and sat in the front (its a bowrider) I idled out of the no wake zone and gave it some throttle and she bogged down - nothing then stalled. Fired right back up, tried again same thing. idled back to the dock and dropped the wife and kids off, went by myself and gave it throttle and it took right off - again up to 30mph and aroundd 4450 4500 rpm but something does not seem right (obvioisly the weight in the front causing the motor to bog) but the lake was rough and when I would hit waves on plane or on a turn i would hear variations in rpms. Also idle rpm's fluctuate considerably. Coming off wot to full stop, idle stays up to around 1000 then gradualy decreases to 750 then 690 and sometimes then stalls. Other times idles fine. Sorry for rambling but this is drivingn me and my family crazy - should have never touched the carbs (i'm still getting the same top end and wot rpms as before with added problems)Seems like its a carb adjustment and the mechanic just didn't have it set right or something. Weird that the weight affected throttle response and would cause the motor to bog down. I kept trying and took my older daughter out just me and her and went fine for thee most part - some hickuping and variation as before but just didn't feel right. - Does this sound like a carb adjustment issue (idle and fuel/air mixture) and the mechanic i had working on it didn't know how to properly set it (fyi - he originally made the adjustmetns on muffs and when i first picked it up I couldn't get it running at all). Again sorry for the rambling but i'm just frustrated and want to get my boat back running at least the way it was before the damn carb rebuild - arrgghhh!!!
 
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