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40hp 402 Engine hickuping and gutless

im guessing no reply by anyone means what i showed in video is perfectly fine then??? and that the timing is not the problem as you seen in video that guys marks he had when he retimed this engine if he did it right who knows.. i bought it as a running engine and sure it runs just bogs out

well here i did a new one set the rpms at about 1000rpm's still can not get it to run youll see in video how the rpm changes after it goes in gear and back in neutral youll see how i set 1/4 turn and stalls engine and back 1/4 i back at 1 1/2 turns

so i stuck

here is video
https://youtu.be/3RdBzR1x0d8
 
so is it working the right way.. why does it still stall? as i figured it shouldnt stall at any time

cant yet need a truck waiting for parts... didnt wanna drive down the road with the tractor pulling a boat lol
 
Your adjusting the slow needle wrong. Slowly turn it in until it stumbles just before it stalls and back out until it coughs or loads up. You adjustment is somewhere in between those two points. Once you get it on the water final the adjustment after running it WOT for 10 minutes or so. Go back to slow and do the same thing in till it stumbles and out til it coughs and split the difference. Mercs like it a little rich and it protects the engine so add 1/8 to 1/4 turn rich or counterclockwise. I am not convinced your tach is correct. Can you borrow a tach timing light from your local auto part store to confirm the engine rpm?
 
Whenever in doubt always run a two stroke outboard on the rich side running leans is the same as running low on oil it will damage bearings and rings.
 
ah ok and the tach i using is just a OMC and i set it to 6 on the back.. what number should they be set at

and is a tach timing light and a timing light the same? ill see if i can find a friend that has a timing light as i know i can buy one but they 90 bucks

and ok tommorow ill try again ill turn slower to try to stumble it... and are you thinking the idling is too low?
i forget who told me on here that said 12 was the poles and i figured divde by 2 for north south pole magnets.. unless it needs to be on a different number..

but ill see what i can find id like to get a clamp on tach guess goes over the plug wire...

but ill look what i can find
 
I hate repeating myself turn the needle in until it stumbles and out until it coughs the setting is between the two. The engine must be fully warmed up in forward gear in the water. If that does not work then you have other issues. You will need a manual and do a proper engine sync. Do you have a manual?
 
According to my manual all the 402s have the same throttle pickup specs. The throttle butterfly on the carb should just begin to open at 6 degrees before top dead center and max spark advance is 27 degrees before top dead center. When adjusting the slow needle the carb must be fully closed engine idle speed is dependent on spark advance not throttle opening.
 
i dunno why you keep repeating yourself.. you watched every video i posted and it shows you that it stumbles. and when i turn 1/4 turn back im exactly at 1 1/2 turns from closed.. thats it.. and you seen that it always stalls out i did what you said... close fully.. turn screw 1 1/2 turns out.. you seen it in gear.. and it was idling in gear for 20 min at slow speed so that was plently warmed up.. i turned it clock wise till it stumbled as you seen in many videos and that was at 1 1/4 turns... so 1/4 turn back is 1 1/2 turns out... and still stalls

i showed you in the videos what i changed and the idle.
no i dont have a manual i trying to sell boat i only bought engine to replace a small 35 evinrude..

i told you the guy before me supposedly tuned engine reason why he marked on the fly wheel the white points ... and reason why i said i had to tighten that one nut.... and last posts was about a timing gun

and i spent about 5 hours already back and forth with the damn from 1 turn to 3 turn outs and then trying to punch so it goes fast and not dies instantly as i posted that article for setting the idle.. says in there punch the throttle. so i followed there instructions

thats why i asked you guys if the timing is off but you guys didnt say anything that it can be timing you said its only the fuel mixture screw well like i said i have spent 5 hours going back and forth from 1 turn out to 3 turn outs doing very small increments..

now last email was about tach OMC being not the right RPMS i got a tach o meter. its close
here is the video
https://youtu.be/CC8N0tg16Mg


and im not sure the 27 degree mark i can send a pic tommorow... the guy marked TDC in white and another spot white but i cant tell you if that is 27 degrees.. and if the butterfly is fully closed thats then idling really low and i guess thats in gear? so what that be like they mentioned 700-800 as this engine doesnt like that but ill fiddle again tommorow
 
kimcrwbr1 said:
According to my manual all the 402s have the same throttle pickup specs. The throttle butterfly on the carb should just begin to open at 6 degrees before top dead center and max spark advance is 27 degrees before top dead center. When adjusting the slow needle the carb must be fully closed engine idle speed is dependent on spark advance not throttle opening.
Click to expand...


ok i not sure where 27 degrees is on the flywheel just guy marked 2 lines 1 line TDC and another line left of the TDC... and how do you do set max spark advance and in that video where i showed you guys i tigthened that nut under the flywheel what is that.. as that as just loose as a fart..

and i spent an hour today trying to set the mixture screw i set it to 1 1/2 turn out and i turned it like 1mm clock wise waited 5 seconds like you guys said then moved another 1mm turn waited 5 seconds now the engine stumbles anyways as you see in video between 500-800 on its own so i kept doing that so in end i got it kinda what i guess stumbled between 1 1/2 and 1 1/4 turns so when i do a 1/4 out from in between that and i punch it like the article says to do.. she still stalls so then i was doing 1mm turns from 1 1/2 to 2 turns 1mm at a time and 5seconds pause still stalls..

i notice when i go back to neutral and put back in gear it idles faster i have to go back to the throttle and and manualy pull it tight to the idle stop screw i guess that means you need to tighten the throttle cable ...
but how do you set the 6 degrees open on the carb throttle just before TDC.. i turn the flywheel by hand to get to TDC carb throttle doesnt do anything so am i missing something there
 
since i dont have a timing gun i cant test it to see if its done right
but here is video of the fly wheel the mark for TDC i checked ya she in right spot.. then the other line is that the 27 degrees mentioned
here is video
https://youtu.be/MvF7FXqVCK0

78 teeth i guess and 73 is the 2nd mark

let me know if that is right etc
 
Yeah, but you need to borrow a light and check it.

So you know, WOT timing has nothing to do with idle, or stalling when gently dropping her into gear.

Jeff
 
fastjeff said:
Yeah, but you need to borrow a light and check it.

So you know, WOT timing has nothing to do with idle, or stalling when gently dropping her into gear.

Jeff
Click to expand...

ah ok well i didnt think the WOT has anything to do wit hthe idling is the punching it from idling in gear and it just stalling right out and me spending couple hours just turning needle screw like 1 milimiter at a time and waiting 5 seconds between each time has had no effect thats why i asked what that arm under the flywheel is why the nut was loose i tigthened and if if timing might be out since i have replaced both plugs, changed pump, cleaned filter, and changed carb kit.. and compression is 150psi... only other thing i noticed is if i had it idling in gear and adjusted it to idle at 1200 1500 rpms you could punch it and wouldnt stall so thats why i figured maybe could be timing... would that be possibly timing as like i said i spent so much time on this idle mixture screw and no setting stops it from stalling out when you go from idle gear and pushing it all the way forward fast.. if you push the throttle slowly it doesnt die.. but i find if i do get it to go fast and i pull to neutral and punch it again it doesnt stall only stalls intitially from gear idle speed punch it stalls..... slowly push forward it will go fast pull back to neutral it idles higher and you punch it again or put in low gear and punch it forward it accerelates fast like no issues.. so thats why i figured maybe timing.. as i have done everything i thought i could except timing...

and how do you do timing never done that before
 
Most perceived " carburetor problems " turn out to be something else.------------So more trouble shooting needs to be done.
 
racerone said:
Most perceived " carburetor problems " turn out to be something else.------------So more trouble shooting needs to be done.
Click to expand...
figures eh.. from what i experiencing what could it be? after you seen the check list i checked off
also i have replaced the connectors and the fuel line hose and new bulb

now i could use help in the timing gun as i know you point gun at a white marker thats about it lol
 
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