'72 650 will NOT idle and dies

myelo

Seaman Apprentice
Joined
Jun 1, 2003
Messages
41
Okay, here is what I have done. Carb kits (2), new plugs, new water pump kit, new fuel pump kit, new fuel lines/primer bulb, new gas. <br /><br />I cannot get the dang thing to idle. I have worked those idle screws (in water) every which way and cannot get the thing to idle. I have to use the warm-up lever (which revs it) then QUICKLY pull it down and put in gear to get it to do, otherwise, it dies.<br /><br />Also, once I get going, it will go for a while, then die and not start unless I squirt starter fluid in the carbs (the only way I could get back to shore, so had too!). <br /><br />After warming up, as soon as I put the warming lever back down....dies. No amount of adjusting on the idle screws/mixture screws works. <br /><br />I replaced the floats, needles, gaskets on the carbs. I don't see anyway to "adjust" the floats. Any suggestions are appreciated. U can also email me w/suggestions at sfarrisrn@aol.com. Thanks!
 

timmathis

Lieutenant
Joined
Apr 24, 2005
Messages
1,295
Re: '72 650 will NOT idle and dies

Don't use starting fluid!!! No luberacation.
 

AMD Rules

Lieutenant Commander
Joined
Sep 23, 2004
Messages
1,707
Re: '72 650 will NOT idle and dies

Have you checked cylinder compression?
 

myelo

Seaman Apprentice
Joined
Jun 1, 2003
Messages
41
Re: '72 650 will NOT idle and dies

Tim, yes, compression is 115 all three cylinders.
 

myelo

Seaman Apprentice
Joined
Jun 1, 2003
Messages
41
Re: '72 650 will NOT idle and dies

oops, I meant to address compression to AMD...sorry.
 

joblo33

Chief Petty Officer
Joined
Jan 19, 2005
Messages
501
Re: '72 650 will NOT idle and dies

I had this problem with my merc 50 before my coil cracked and I had to replace it. After replacing the coil it would idle fine, how strong is your spark?<br />Eric
 

morge

Cadet
Joined
Jun 12, 2005
Messages
13
Re: '72 650 will NOT idle and dies

I should start a new forum, but seeing as I spotted you have the same engine as mine....can you tell me what the three wires off of the front of the control box are for? My 650 starts, runs, and this three wire harness doesn't go anywhere. It has a green, a white, and a black wire. With engine off, I get 12V between black and green, and 13V across black and white. Would I be so lucky as to get a tach signal off of the green?
 
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