Why hold the choke while starting?

USAFitz

USAFitz

Seaman Apprentice
Joined
Apr 27, 2007
Messages
36
1970 Mercury 650

I have read on the forum about a bunch of people who depress the choke button for about three key turns before they let it go and start the engine. Can anyone tell me what that does? My engine often seems like it's flooded and won't start. The starter turns the flywheel, but won't turn over. So I tilted the engine to let the fuel out of the carb and it fired right up. Is that choke button going to be a good technique when it won't fire up? Thanks for the info.
 
J

jmburock

Petty Officer 2nd Class
Joined
Aug 25, 2005
Messages
174
Re: Why hold the choke while starting?

USAFitz said:
1970 Mercury 650

I have read on the forum about a bunch of people who depress the choke button for about three key turns before they let it go and start the engine. Can anyone tell me what that does? My engine often seems like it's flooded and won't start. The starter turns the flywheel, but won't turn over. So I tilted the engine to let the fuel out of the carb and it fired right up. Is that choke button going to be a good technique when it won't fire up? Thanks for the info.
Click to expand...

I do the same thing sometimes with my motor (pour out the fuel) and it starts perfectly.. Too much choke and it floods. Sounds like I may need a carb rebuild but this technique works for me (albeit a bit environmentally unfriendly and messy).
 
tashasdaddy

tashasdaddy

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51,019
Re: Why hold the choke while starting?

your carb floats are not closing properly is why the carbs are over flowing. most inline merc like to be nearly flooded to start when cold.
 
USAFitz

USAFitz

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Re: Why hold the choke while starting?

so wouldn't being almost flooded be somewhat the same as the carb over flowing? Please forgive me if I sound un-educated on this on, because I am :)
 
redjmp

redjmp

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Mar 16, 2005
Messages
536
Re: Why hold the choke while starting?

I had to do the same thing with my old '65 650. Just a quick shot of the choke when first cranking then let go and it would then fire right up.
I don't think there is anything wrong with your carbs, its just the way it works. You could probably adjust the choke so as to not shut off the air as well as it does maybe by drilling a couple of small holes I guess or adjusting the linkage some...
 
Scaaty

Scaaty

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May 31, 2004
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5,180
Re: Why hold the choke while starting?

Try something real simple...try starting it BEFORE choking...maybe it don't need extra gas..(high float levels will suck it in)
 
Texasmark

Texasmark

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Dec 20, 2005
Messages
14,558
Re: Why hold the choke while starting?

Scatty you're too much. Grin

I have heard others on here comment on the fact that they don't need to choke their engines. Well, how long since the last use surely plays into that. Usually mine sit for at least a week and they need to be choked, the tower especially.....but when on vacation with daily use, don't need it.

Mark
 
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