Re: Throttle linkage - WOT
Originally posted by strawberry mivi:<br /> When bought took it to an outboard mechanic for a service - all the usuals, plus a tune up.<br /><br />He obviously wasn't a Force expert because the throttle cam was set forward of the alignment mark, opening the throttles in the carbs. I spotted this and released the throttle linkage, adjusted their length and aligned the mark to the eccentric screw.<br /><br />Now when started the engine wouldn't idle, it started fine, so ended up returning throttles to their 'original' position.<br />
<br />Welcome to iboats.<br /><br />Did he do a copmpression test? The condition you describe can be caused by;<br /><br />low compression,<br />deteriorated fuel pump diaphram.<br />air leak in fuel line somewhere.<br />or a partial obstruction in the carb's pickup tube,or jet.<br />carbon buildup anywhere in the exhaust.<br /><br />I'm sorry i can't narrow it down any, but actually, there are other causes (rare ones) in addition to those.<br /><br />
Originally posted by strawberry mivi:<br /><br />Motor seems to run fine but -<br />I realise the idle mixture must be wrong for it not to idle when the discs are closed<br />and<br />I've noticed the throttles don't open to WOT position when the control is pushed fully forward.<br /><br />So i know i have to adjust the idle mixture (in water, not on muffs) but are my cables set up wrong or is the linkage to blame?<br />mivi out
To adjust the throttle linkage-- motor off, at WOT, to the point where the butterfly is fully open.<br />The mixture adjustment should never change after being properly set. If the mixture has been properly adjusted, or the settings seemed to change, there is an internal reason, just as those causes i gave you above.<br />A couple of the more rare causes: a reed stuck partially open, timing (also does not change after set), loose carb, or it's flange gasket is leaking.<br />EDIT:To properly adjust mixture:<br />Again, this is a set-n-forget adjustment.<br />Run the motor until it reaches operating temperature.<br />TEMPorarilly set the throttle linkinage to where the motor will idle.<br />Now, turn the idle screw out (Counter-clockwise) 1/8th turn, and wait for 10 seconds. Note any change to rpm or performance. keep doing this 1/8th turn and 10-second wait, until the motor has reached a point where the rpm no longer increases, and go clockwise 1/8th turn. The motor should no longer be stunmbling at this point either.<br />This is proper adjustment RICH. This is where i always set them, even if the motor fouls plugs quicker (60hours as opposed to 80 hours between replacement), and the motor will need more frequent decarbing. But the motor will run forever like that. A lean fuel delivery for 2 cycles can cause an early demise, so i err on the side of RICH.
<br />Let it foul all the plugs it wants to.
