come on guys help me please

seantim

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Jul 21, 2005
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1976 75hp rude just boggs down comp is good 120 on all 3 seems to have good spark i set timing @12degrees with plugs out @wot it calls for 16 and about 7/16 spark gap carbs seem to be clean as i took them apart and cleaned them and done a link and sync even took head off cyls look great put in new ql77v plugs i just got a set of 1981 65hp carbs that are clean as a pin inside and out and all passages are clear i will put them on and try them but it just seems to have no power help please i hope this post is not too long just trying to cover what i done oh and took flywheel off and key is not sheared firing seems to be good also hey i'm begging for help!!!!!
 

lark2004

Lieutenant Junior Grade
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Jul 12, 2004
Messages
1,080
Re: come on guys help me please

ok, punctuation would help. <br /><br />Now, Did you say you set your plug gap to 7/16 ????<br /><br />It sould be about .030" . <br /><br />The 7/16" gap is for spark testing only. This is to make sure that the ignition system can make a proper spark when it is under compression.<br /><br />I also noticed that you pulled the head off?<br />Did you put a new head-gasket in when you put the head back on?
 

BoatBuoy

Rear Admiral
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May 29, 2004
Messages
4,856
Re: come on guys help me please

Don't have any thing to add at this point, but just curious. If compression was 120 lb on all 3 cylinders and no suspicion of anything wrong there, why in the world would you pull the head off?
 

seantim

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Jul 21, 2005
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Re: come on guys help me please

plug gap is at 040 and the reason for pulling the head was i thought maybe water was getting in a cyl but i was wrong it was in great shape and i checkek the head to make sure it was straight and installed a new head gasket and torqued it according to the manual
 

Goodoleboy

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Joined
Nov 20, 2003
Messages
555
Re: come on guys help me please

I kinda suspision that you mite wana recheck your link and sync.<br /><br />Bogging down and then finialy building up RPM'S is indective of carbs opening before timeing advance starts to move.<br /><br />Also the reverse is true. Timeing advance moveing before carb. butterflys begin to open.<br /><br />That sequence has to start precisley togather.<br /><br />Good Luck!
 

seantim

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Jul 21, 2005
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Re: come on guys help me please

never builds up rpm just boggs down
 

OBJ

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Dec 27, 2002
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10,161
Re: come on guys help me please

Take a look at the cam on the starboard side of the engine. It lays aginst a roller on the middle carb. On the cam is a reference mark. When advancing the throttle, the reference mark should hit the roller midpoint and the carb throttle plates should just be stating to open. Check that.<br /><br />Any leaks around in the fuel system? When have the carbs been overhauled with kits last? Is your fuel tank venting? All fuel hoses plyable....none are hard from years of use? <br /><br />I'm leaning toward the fuel system cause that's where I think the trouble lies. Usually, when an engine bogs, it's cause it's getting to much fuel or as Goodoleboy posted, the sync and link is outta' kilter.<br /><br />So, give us some info and most likely we can help.
 

seantim

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Jul 21, 2005
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Re: come on guys help me please

thanks obj for the comeback and i just put a fresh set of carbs on the engine new hoses for fuel and on the link and sync i am moving the roller off the throttle plate and starting the engine and adj. the idle screw so that the timing lite is showing tdc then put the roller back to the plate on the mark then moving the rod on the cam yoke to achieve correct idle speed is this correct? oh and the gas tank is built in and has new lines and when i pump up is stays hard even when i run on muffs it stays pumped up good it just feels like its running on 2 cyl sluggish i would say
 

Goodoleboy

Chief Petty Officer
Joined
Nov 20, 2003
Messages
555
Re: come on guys help me please

Pull plug wires one at a time and see if any have a big change or no change at all.<br /><br />Then switch coils from strong one to weak one. If problem follows coil then replace.<br /><br />Try same thing with carbs. switch good cyl. to bad cyl. if problem follows carb. then rebuild and clean..clean....clean...and then clean it again.<br /><br /> remove welch plugs. And check lead shot plugs to see if they are lose. and leaking air.<br /><br />Good luck!
 

seantim

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Jul 21, 2005
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48
Re: come on guys help me please

goodoleboy or someone was my link and sync in this thread the correct way?
 

seantim

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Joined
Jul 21, 2005
Messages
48
Re: come on guys help me please

thanks to all who helped and i think i have found my problem!!!! when i turn motor up to about 2000 rpm and pull plug wires one at a time the top and bottom will make the engine die but the middle only slows down the rpm won't make it die switched the coil to the top and still the same middle cyl.just slows it down is it my power pack or stator i rechecked the comp and is 120 on all cyls what do you think
 
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