View Full Version : Mercury 75hp Idle jet settings
spybot
06-26-2018, 03:50 AM
I picked up a a 1985 75hp Mercury
When i got it the idle jet needle screws were missing.
I have got 2 new ones but cant find the settings any where online.
Tried them lightly seated then turned them 1 & 1/2 out but she wont start never mind idle.
Can anyone give me a pointer in the right direction ????
FLATBTM
06-26-2018, 10:03 AM
Every thing else been verified? Just curious what else could be missing if idle screws were gone.
I would bet money that it's around 1.5 turns out, but I can't verify that. Fatten it up gradually to see if it starts trying to kick.
spybot
06-26-2018, 10:27 AM
Do i wind out to fatten mix ?
spybot
06-26-2018, 10:30 AM
Should add
Always worked on OMCs with fixed jetting.
I have removed both crabs and thoroughly cleaned them.
She only wants to start with some carb cleaner sprayed in the carbs while cranking.
I think she may not be getting enough fuel to start but how would i know this for sure ???
FLATBTM
06-26-2018, 11:04 AM
Counter clockwise to fatten, yes.
When your cranking on it see if squeezing the bulb changes anything. Could also pull the hose and see if it pumps fuel while cranking.
spybot
06-26-2018, 12:42 PM
I have tried squeezing the bulb it stays hard all the time no difference whilst it cranks and the bulb is being squeezed.
I will check the pump. When it did start (Hard to believe it would start) But it did that was done by spraying the carb cleaner straight down the carb throats so maybe it is not getting enough fuel to start her.
mn808gade
07-02-2018, 11:08 PM
gravity fed primer?? change it to pressure fed. btw does fuel drain out of feeder from carb bowl to primer ,now?-th
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