proper way to start 140 merc I/O

Joined
Dec 17, 2004
Messages
14
Having no owners manual and always having outboards before, I have a question...<br /><br />What is the proper/best way to start this engine?<br /><br />Neutral, pump it full one time, back to center?<br />OR....<br />Neutral, go forward to first indent/position?<br /><br />It's a 1985 Four Winns Horizon 170.
 

Northern Eclipse

Senior Chief Petty Officer
Joined
Jun 24, 2003
Messages
665
Re: proper way to start 140 merc I/O

Well thats a good question, but most the time I start by locking control into neutral and give her 3 or 4 good pumps then pull throttle back just under 1/8 throttle, turn key if it starts then I adjust throttle till engine is turning 1000-1200 rpm for a minute or so then bring down to idle, if is does not catch, few more pumps and try again. Its hard to say exactly how you should start since these a carb'd motors and air temperture is really going to dictate how it wants to start and it seems each motor has its sweet spot when it come to starting sometimes I don't need to pump the throttle at all.
 

trog100

Senior Chief Petty Officer
Joined
Dec 1, 2004
Messages
751
Re: proper way to start 140 merc I/O

i have the choke disconnected on mine.. in the winter it takes six or so pumps and a couple of tries before it fire and keeps running.. in the summer 3 or 4 pumps and its fires up first time..<br /><br />half throttle should be about right.. never try and start it without at least some throttle it will probably flood if u do..<br /><br />my problem is i cant judge exactly where the throttle is set i have no indents just a frictional lock kinda thing.. and without the engine running its pure guesswork.. <br /><br />with choke the danger of flooding is more likely so a couple of pumps and in summer praps even no pumps and plenty of throttle and back it off as soon as it fires..<br /><br />i leave mine running for a few minutes before moving off cos i need a reliable idle..<br /><br />basically the less thottle u use on a carb engine when u cold start it the more chance u have of the mixture being over rich.. the more throttle u use the less critical it all becomes.. i dont like firing up cold engines with lots of throttle but with my boat engine i have to like it or not..<br /><br />i just make sure i back it off quick..<br /><br />chokes are crude ways of giving a cold start rich mixture.. they aint exact.. plenty of throttle just makes it all less critical..<br /><br />trog100
 

rodbolt

Supreme Mariner
Joined
Sep 1, 2003
Messages
20,066
Re: proper way to start 140 merc I/O

what ya wanna do is pump the thgrottje 2-3 times with the shift disengaged and learn where the point is that when the engine fires up it goes to about 1200-1500 rpm. let it idle there for a minute or so and slowly pull it back.if it fires at 2000-=2500 rpm its no worries just back it down to 1100-1500. the object is dont let it lean sneeze and cut off. they tend to suck water in that case.<br />I would rather see a cold motor start at 2K than 700 anyday. means the oil is pumping harder and faster and slinging more. the cam lobes on that motor are splash lubricated.<br />more splash is more lube.
 

trog100

Senior Chief Petty Officer
Joined
Dec 1, 2004
Messages
751
Re: proper way to start 140 merc I/O

tell u what bothers me rodbolt and i always listen for it.. kind of habit.. there is brief period of about no more than two or three seconds before the oil under pressure gets fed to the big-end bearings.. if the engine has a simple oil light its the brief period till this goes out..<br /><br />during this period u can hear em tap just a little.. the tapping shuts up the instant the oil gets there.. on some engines its hard to hear on others its more noticable.. on a worn engine its very noticable..<br /><br />i just dont like the idea of revving an engine till the oil gets round to those soft big-end bearing.. he he<br /><br />rightly or wrongly i worry more about the bottom end bearings than i do the cam lobes.. <br /><br />there is probably enough residual oil there for it not to matter anyways but it just bothers me and i always listen for it.. he he<br /><br />still.. its a very good test for bottom end wear so it aint a bad habit even if it is a bit paranoid.. he he.. <br /><br />trog100
 

SteveRay

Petty Officer 1st Class
Joined
Oct 20, 2004
Messages
338
Re: proper way to start 140 merc I/O

Guys I was always told only one pump and that sets the choke. ANymorethan one pump and you are in danger of flushing your cylinder walls clean. Pumping it washes all the oil off the cylinders with the incoming gas. Furthermore you run the risk of diluting your oil with gas. <br />I could be wrong but just thought I would share what I have read.
 
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