1991 90 hp burping-sneezing sound

!991 mercury 90 hp 3 cylinder,I rebuilt carbs fuel pump,fuel filter,put a new enrichening devise on.checked compression,and spark and there all fine.Motor starts great most of the time,Idles real good.But smells like its running rich.Even runs to full throttle with no miss.But if I throttle it up real quick and back down to idle it makes a burping -sneezing sound and stalls.some times.If I go from full throttle to Idle to Quick It makes that sound also and sometimes blows the little hose off that runs from top of the crank too the bottom of the crank,Then its a pain to get started.Also when throttling down quickly and it make that sound seems like smoke is coming from between the powerhead and exhaust leg.If I pull the little hose that is connected from the bottom of crank case,it smells like raw fuel.A friend of mine said that the gasket between the powerhead and exhaust leg will make it make that sound if its bad.seems to me there a lot of cranck pressure.but I'm no expert.But I like to no what you guys think before doing anything.Thanks in advance for any information

Re: 90 hp burping-sneezing sound

You're idle mixture is off. One (or more) of your carbs needs to be richer.

Jeff

Re: 90 hp burping-sneezing sound

Ok wil try to richen it up.how do you tell if the gasket between the powerhead and exhast leg is ok.Is there a way.And thanks for the reply FastJeff

Re: 90 hp burping-sneezing sound

...".how do you tell if the gasket between the powerhead and exhast leg is ok"

If it's not leaking water out.

Jeff

Re: 90 hp burping-sneezing sound

fastjeff said:

...".how do you tell if the gasket between the powerhead and exhast leg is ok"

If it's not leaking water out.

Jeff

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There is some smoke coming from that area,think its exhaust or oil smoke though.Is there some exhaust jacket in that area,That has a gasket or a seal,that could be leaking,making smoke come from lower crank area.