Merc1000 1968 Questions

[tengals123]

ok, have taken the carbs off and rebuilt. Now what am I missing here. When they say turn the idle out 1 1/2 turns from lightly seated position? <br />1.<br />When I dismantled the carbs all idle screws were screwed in 9 turns, that's right 9 turns and idle fine. So I put the needle in and screw IN 9 times and that was the position they were in. So my question is 'lightly seated' and turn OUT, am I doing this in reverse or what?<br />2.<br />My carbs do not open at WOT fully, it hits the 'spark advance screw at about 80%, can I just back the screw out untill the carbs are fully open at WOT?<br />Any replies would be great!<br />Thanks heaps.<br />cheers

 

[AMD Rules]

Re: Merc1000 1968 Questions

The needle position should be adjusted from the closed (seated) reference point, to compensate to tolerances in needle dimensions. The profile of your original needles will likely be greatly different (worn) than your new needles, thus you need to gently seat them by screwing them all the way in, and then back them out accordingly. This sets the gap spacing between the needle and seat, and is what regulates the fuel flow. Adjusting the new needles by screwing them in 9 turns, would leave the gap spacing unknown and could result in poor performance.<br /><br /><br />Here's an excellent post decribing the needle setting position, and subsequent timing etc...<br /> Timing and Sync of Merc Inlines (to 1988)

 

[Laddies]

Re: Merc1000 1968 Questions

Tengals, one of the things to ck when you find low speed needle out so far is the low speed pick up tube they tend to get varnished up on the inside some times it takes a tip cleaner to open then up--Bob

 

[Clams Canino]

Re: Merc1000 1968 Questions

You need to set the advance screw for 34-35 degrees MAX advance. If your carbs won't open at full throttle that's another adjustment.<br /><br />The manual has a decent step x step tuning procedure.<br /><br />-W

 

[tengals123]

Re: Merc1000 1968 Questions

thanks clams, I havent moved it yet. I am waiting until the motor is back on the boat. I did notice the throttle advance was all the way in, meaning I cant advance it forward anymore to open the carbs.<br /><br />cheers