Mariner 90hp (1994)

[texas-t]

Could someone give me the initial settings for the carbs on a 90hp Mariner?I recently had the carbs rebuilt at our local boat shop because of excessive smoking. now i have a motor that is extremly difficult to start and will die if i try a "hole shot". i looked at the adjustment screws on the carbs the top and middle are open about 1/4 turn but the bottom is 3 1/2 turns open.Thanks in advance

 

[Bob Kimber]

Re: Mariner 90hp (1994)

Hi Texas-t<br /><br />When fine tuning my 90 3cyl Merc, I didn't have access to a manual at the time but I found the best setting was about 1 3/8 turns out from lightly seated on the middle and bottom carbs and about 1 1/4 turns on the top carb. Clymer manual says starting point about 1 1/4 on all carbs (from memory), the mixture screws are very sensitive 1/4 turn can make a big difference. I am currently trying to get an OEM manual as I get lots of different opinions both from this board and supposedly experienced Merc mechanics. You need to do final adjustments with boat in the water, a test tank will not give the right results. As a matter of interest mine runs great at this setting (for about two years now), no smoke when in the water with a good idle, an acceptable bit of smoke when flushing motor in a tank. I think the bottom carb setting is way too much, maybe your link and sync is also out of adjustment.<br /><br />Bob