1972 125hp evinrude idle problems

jonnymarquis

Petty Officer 2nd Class
Joined
Feb 25, 2010
Messages
151
ok i once posted about the idle issue, it would crank but in order to keep it running i had to choke about every 5 seconds. now i can get it to stay running once it warms up but i can not let it idle down at or bellow the start position or it dies now i have replaced the primer bulb checked the gas lines for leaks and pulled the carbs soaked them and cleaned them to a shine. the problem still exist. will not idle low, i also did a compression test each cylinder stayed around 60 psi give or take a psi after 2 seconds each. what else might i check? it does not have a tach so i can not tell you how fast its running when it stalls, but its not that slow, and it just slows it self down and dies, ty for the help
 

mitchell6

Petty Officer 3rd Class
Joined
Mar 24, 2006
Messages
93
Re: 1972 125hp evinrude idle problems

you got a bad motor if all your cylinders are at 60 should be up around at least 100 on each one
 

jonnymarquis

Petty Officer 2nd Class
Joined
Feb 25, 2010
Messages
151
Re: 1972 125hp evinrude idle problems

maybe its a low compression motor or i just didn't run it enough idk
 

jonnymarquis

Petty Officer 2nd Class
Joined
Feb 25, 2010
Messages
151
Re: 1972 125hp evinrude idle problems

good news i must have overlooked a bolt on the fuel pump i guess that is what caused the problem, tighten the bolt down now she puers like a kitten. maybe it was sucking air idk know but it working fine now, and anybody that knows the compression on this motor please let me know or if i done it right or not.
 

mitchell6

Petty Officer 3rd Class
Joined
Mar 24, 2006
Messages
93
Re: 1972 125hp evinrude idle problems

when doing the compression check do it with all spark plugs out, should be somewhere around 115 but most of all they all 4 need to be within 10% of each other
 

emdsapmgr

Supreme Mariner
Joined
Dec 9, 2005
Messages
11,551
Re: 1972 125hp evinrude idle problems

That engine came with very high compression heads right from the factory. It came with over 130 lbs compression on each cyl. when new.
 
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