'91 60hp Low Speed Screw Settings Factoy Spec??

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reliablesources

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Hello Guys. New to this forum but know how it works.
If there is an answer to my question already on the forum, you can link it to me to keep from repeating ourselves.

Just bought a 91 Evinrude 60hp for a project. All is good except it spits at idle and mid throttle. Carbs are clean. Found Low speed screws as follows:
Top carb 1.25 out
Middle carb 1 out
Bottom carb .75 out

If i give it a manual choke it lines out just for a second. Seems like its not getting enough fuel. Do these screw setting sound odd to you. Factory service manual says to start at 2.25 out then adjust (assuming for all three carbs). And why would someone lean the carbs as they go down. if the settings are correct, why?? What should the settings be if they are not correct?
I know the duel cylinder, duel carb jetski setups but not sure about the vertical tripple outboards.

Thanks for the info

Tony
 
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ezeke

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Re: '91 60hp Low Speed Screw Settings Factoy Spec??

The initial low speed settings should be 2 to 2-3/4 turns out from gently seated.

First, by observation, determine that the throttle plates are closed when the throttle is in the idle position and that the plates remain completely synchronized as they move through the range of motion to fully horizontal at WOT.
 
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reliablesources

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Re: '91 60hp Low Speed Screw Settings Factoy Spec??

sync is good.
so the low spd screws setting are no where near correct at 1.25, 1, and .75 out. they should all be the same (somewhat)?
 
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backyard mechanic

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Re: '91 60hp Low Speed Screw Settings Factoy Spec??

reliablesources said:
Hello Guys. New to this forum but know how it works.
If there is an answer to my question already on the forum, you can link it to me to keep from repeating ourselves.

Just bought a 91 Evinrude 60hp for a project. All is good except it spits at idle and mid throttle. Carbs are clean. Found Low speed screws as follows:
Top carb 1.25 out
Middle carb 1 out
Bottom carb .75 out

If i give it a manual choke it lines out just for a second. Seems like its not getting enough fuel. Do these screw setting sound odd to you. Factory service manual says to start at 2.25 out then adjust (assuming for all three carbs). And why would someone lean the carbs as they go down. if the settings are correct, why?? What should the settings be if they are not correct?
I know the duel cylinder, duel carb jetski setups but not sure about the vertical tripple outboards.

Thanks for the info

Tony
Click to expand...


FONT="Comic Sans MS"]Tony starting with carb adjustments is like putting the cart in front of the horse. Never a good idea. If this is a project OB then you would be smart to start from the beginning. Compression checks are ALWAYS number one. Next, move on to lower end. Check it for water and if it holds pressure. Now that you know the OB has potential move on to carb FP rebuilds if necessary. Then just before running assure ignition components are OK, connections tight, new plugs set if needed. Your next step is adjust/set your primary timing, synchronize the timing to the carbs, WOT to secondary or WOT timing spec. Once all that is s it should be move to the idle/carb settings.

As said, the carbs need to be set so that the throttle plate is closed on all 3 carbs and at WOT they are indeed at WOT. The primary timing set so that at the touch of the throttles opening your timing is at spec. Then set secondary or WOT timing. With the newer OB's that can be done with spark test and moving the throttle to "that" setting. When it sparks, you're on timing. Carb settings usually start with 1 1/2-2 turns out but what ever the turns out just be assured that each cylinder has appropriate fuel/air ratio once you are done. Follow the manual... You'll be glad to did. [/FONT]
 
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reliablesources

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Re: '91 60hp Low Speed Screw Settings Factoy Spec??

yep, took it to the doc with no fire and he changed the power pack and timer coil. we didnt get into the carb setting because i was happy it ran. now im at the carbs and why its tuned the way it is. I will put set the screws at 1.5 out each and start there. lower unit good. put new trim motor on it.
 
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ezeke

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Re: '91 60hp Low Speed Screw Settings Factoy Spec??

tashasdaddy said:
http://shop2.evinrude.com/ext/index.aspx?s1=bf6ad09c53cead335fcfd8a6471c0f7f

#15 in diagram needle valve slow speed is suppose to start at 4 turns out, then adjust.
Click to expand...

Nope, 4 is too rich. And, 1-1/2 is too lean. Use the factory service manual setting "Factory service manual says to start at 2.25 initially" and work from there. The engine will sneeze and backfire if too lean and will be rough and unsteady if too rich.
 
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reliablesources

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Re: '91 60hp Low Speed Screw Settings Factoy Spec??

by the way the jetting is 44D high and 35 low. is that facotry?
 
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