evinrude 120 looper

65whaler

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Hello, here's my question. Underneath the carb cover is 4 small T's that go to a fittings between the carbs. What are these fittings and what do they do? I was told that these fittings were check valves, is this correct? My engine runs fine but dies in nuetral or low RPM in gear. Always have to start it up using the idle lever then slam it into gear. Thanks in advance.
 

reeldutch

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Re: evinrude 120 looper

i think you have a fuel isseu.
might need the carbs cleaned.

their is nothing wrong with slamming into gear.
better then grinding theeth.
 

Walker

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Re: evinrude 120 looper

What year is your motor? The check valve hoses only have one "T" to the bottom check valve. The rest are direct hoses.
 

OBJ

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Re: evinrude 120 looper

Along with the year as Walker suggested, got any maint history on the engine? Is it new to you or have you had it for a while?
 

65whaler

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Re: evinrude 120 looper

Walker said:
What year is your motor? The check valve hoses only have one "T" to the bottom check valve. The rest are direct hoses.

1988, do the smaller hoses connect to the check valves and what is their purpose?
 

65whaler

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Re: evinrude 120 looper

65whaler said:
Walker said:
What year is your motor? The check valve hoses only have one "T" to the bottom check valve. The rest are direct hoses.

1988, do the smaller hoses connect to the check valves and what is their purpose?

I've had the motor for 5 years, bought it rebuilt from a friend of mine. The motor runs fine but has always had the idle problem. Just recently I had the power pak, stator, and timing trigger replaced, I replaced these items due to a spark failure last year. Another problem it had was the holeshot was horrible, but after the electronics replacement the holeshot is great. The only other problem I have is the tach, sometimes it works but never at high rpm. Hope this helps.
 

OBJ

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Re: evinrude 120 looper

The small hoses make up the fuel recirc system. This system takes any fuel laying in the reed cage area, that was not sucked into the engine, and recircs it back to the cylinders. The check valves allow only one way operation.

The poor idle can be anything from the carbs needing an over haul to the engine needing a link and sync.

Does "choking" during idle make any difference in the idle or does the engine want to die?
 

65whaler

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Re: evinrude 120 looper





pushing the choke button during idle will usually kill the engine. If I were to clean the carbs, where are the ports that can have pluggage. My carbs look plastic, is there any specials precautions with this material?
 

65whaler

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Re: evinrude 120 looper

Boat mech. was impressed, said I had 130#'s in each cylinder.
 

reeldutch

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Re: evinrude 120 looper

thats 1 down 2 to go.

check the spark at all 4 plugs.

index flywheel and check the timing at different rpms.

the cylinder nr thats firing should apear close to the timing pointer. it schould not be jumping around.


i do believe this would all be fine.

i think you might look into the fuel system.
fuel pump pressure ok?
all jets clean inside carb?
you say when you press the primer the motor boggs down thats exactly what it should do.
but just befor it bogs down, do you hear a small rpm gain?
if thats the case just even for a split second before bogging down you are having a lean cylinder.
make shure you dont run lean that will destroy the engine.

good luck
 

reeldutch

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Re: evinrude 120 looper

dont soak the plastic carbs in carb cleaner they will warp.
use a crc carb cleaner can and spray trough all passages.
follow up with air.
put new kits on them.

first get a manual.
 

65whaler

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Re: evinrude 120 looper

Spark plugs are new, boat mech. set the timing last week when the timing plate and stator were installed. Does the rectifier have anything to do with the tach being irratic?
 
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