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1986 60HP Mercury Carb question

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94Blue

New member
hey All,
new to this site,
A friend gave me this 1986, 60hp, 3-cyc, Mercury.
I'm trying to revive it, and have it running, jus not well yet.
Compression 140 ish on all cylinders cold, new stator since wires were broken, new trigger this week, good spark, new plugs, fuel lines new and fuel pump works.

Rebuilt carbs with complete kit. When testing at boat ramp, the top carb of the 2 has visible fuel going thrugh the venturi, but the bottom carb doe not.

could this be a reed valve problem, or I need to check that carb again?

thanks,
 
NOT the reeds (especially in this case. Long story.)

Try shooting some fuel into the carbs to get it going. If it does, your enrichener circuits in the carbs need cleaning (an easy on the motor job).

Jeff

PS: You're in luck with such good compression numbers. That's not usually the case with these.
 
fastjeff said:
NOT the reeds (especially in this case. Long story.)

Try shooting some fuel into the carbs to get it going. If it does, your enrichener circuits in the carbs need cleaning (an easy on the motor job).

Jeff

PS: You're in luck with such good compression numbers. That's not usually the case with these.
Click to expand...


Thanks, the enricher works and gets it started already on its own with the key.
The big question is why the lower carb does not have visible fuel on the ventruri when WOT like the top one does. I've cleaned these carbs 2-3 times and did a full rebuild with needles, etc.
That is why I'm wondering about the reeds. Is there an easy way to check them?
thanks,
 
I have the same motor on my boat. I would be hard pressed to see any fuel through the air input throat of my carburetors.
20170221_105134.jpg
When you cleaned them did you take a small copper or brass wire and carefully clean the very small holes around the edge of the throttle plate.
If you are seeing fuel, you probably need to check the float level. I am pulling this from memory, I think the float level is 11/16" but don't hold me to it.
fastjeff might know for sure.
 
FishinLite said:
I have the same motor on my boat. I would be hard pressed to see any fuel through the air input throat of my carburetors.
View attachment 16440
When you cleaned them did you take a small copper or brass wire and carefully clean the very small holes around the edge of the throttle plate.
If you are seeing fuel, you probably need to check the float level. I am pulling this from memory, I think the float level is 11/16" but don't hold me to it.
fastjeff might know for sure.
Click to expand...


I can only see fuel getting sucked into the venturi during WOT, but that is only on the top carb, and when it is idling and I cover up the bottom carb with my hand, and it does not affect RPMs like it does when I cover the top one.
I did not do the wire trick since the manual said not too. but I was tempted.
 
I ultrasonically clean my carbs and make sure the small holes are open with a fine strand of copper wire, so I can't be much more help. My carbs come out of the ultrasonic cleaner looking brand new. But the upper carb provides fuel to Cylinder 1 and 1/2 of the fuel for cylinder 2, the lower carb provides 1/2 the fuel for cylinder 2 and all the fuel for cylinder 3. If you are REALLY sure the lower carb is clean and you have no restrictions in your fuel line, I would then check the spark on cylinder 3.
 
FishinLite said:
I ultrasonically clean my carbs and make sure the small holes are open with a fine strand of copper wire, so I can't be much more help. My carbs come out of the ultrasonic cleaner looking brand new. But the upper carb provides fuel to Cylinder 1 and 1/2 of the fuel for cylinder 2, the lower carb provides 1/2 the fuel for cylinder 2 and all the fuel for cylinder 3. If you are REALLY sure the lower carb is clean and you have no restrictions in your fuel line, I would then check the spark on cylinder 3.
Click to expand...


Hey Thanks,
i'm just a weekend mechanic,
I'll pull that one again and use the wire method. But, at WOT, the main jet takes over ,and I would think I would see fuel vaporzing in the venuri like the top carb.
 
Check the carb again. I was certain that I had covered all the bases but I still found a chunk (tiny) of black junk in my main jet. I never even saw that jet when I was cleaning and changing things the first two times. If you are a marine mechanic, these events occur at a minimum. If not......join the club.
 
hey guys,
to close this thread,
I opened the carbs again and realized on the lower one, i'd pinned the float with the gasket and that is why the lower carb was not functioning.
with the new trigger, and a working set of carbs, cranked right up and did well at idle and WOT at the ramp.
thanks for all the help.
 
94Blue said:
hey All,
new to this site,
A friend gave me this 1986, 60hp, 3-cyc, Mercury.
I'm trying to revive it, and have it running, jus not well yet.
Compression 140 ish on all cylinders cold, new stator since wires were broken, new trigger this week, good spark, new plugs, fuel lines new and fuel pump works.

Rebuilt carbs with complete kit. When testing at boat ramp, the top carb of the 2 has visible fuel going thrugh the venturi, but the bottom carb doe not.

could this be a reed valve problem, or I need to check that carb again?

thanks,
Click to expand...

I'm about to order fuel line for my new-to-me 1986 Merc 60HP 3-Cylinder. Do I need 1/4" or 5/16" line? I know I could pull a piece off the motor but can't get to it before going away for the Thanksgiving feast!

Thanks
 
Thanks, Jeff. I'm pretty sure ethat's what it is on mine too. I'm going to order a length and some clamps so I can start on replacing the old stuff as soon as I get back from Thanksgiving with the family.

Jack
 
Hey guys I have same motor mercury 60hp and cannot get to run.m compression in top cylinder is 90 and other 2 cylinders 120
 
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