Early evinrude lightwin 3hp carb issues..

[jonoman69]

Hey, I know there is lots of info out there about these motors but I thought I'd ask a couple questions. I started fixing up one that was giving to me. Compression was good replaced the ignition system, and did the head gasket for the sake of it. I then cleaned and put a carb kit in. The motor fired right up for me and seems to rev up pretty good. But I can't seem to get it to idle very well. The motor idles down just below the stop setting, fairly slow but not what the motor should do. Then it just seems to bog out, even if I try to catch it with the throttle usually won't. After it dies I can fire it right back up. It we'll stay running fine when revved up it's just the idle. The only other thing I've noticed is when I leave the motor in the garage over night on a stand with the fuel shut off. Fuel seems to seep out around the silencer and carb intake. Also when placing the bowl on the carb I noticed there is no pressure from the boss gasket...would that cause the seeping? Any help would be great looking forward to getting out on the lake trout fishing

 

[boobie]

What was the compression on it ??

 

[Crosbyman]

if fuel is leaking out the carb silencer the float is properly not set right.. it should be parallel to the carb body held upside down ,

do a blow test on the carb inlet

air should go in rightside up and no air should go in upside down

http://www.leeroysramblings.com/OB carburetor_repairs.html

http://www.maxrules.com/fixtuneitup.html

 

[jonoman69]

I'll double check my float setting..would that cause the bad idle? And my compression before I started was 75 the other 73. But that was a cold compression check on dry pistons. I plan on rechecking the compression to make sure the head gasket made a good seal.

 

[jonoman69]

As far as the float goes also the fuel leaks out with the gas off....

 

[lindy46]

Did you remove the plug on the top of the carb and clean the idle circuit? How is the tip of the slow speed needle? Did you replace the float? You may want to adjust the float a hair higher (when upside down) than parallel. This will assure that the gas flow shuts off before the bowl overfills. Idle problem has nothing to do with the float. Compression readings are good.

 

[jonoman69]

I didn't replace the float but it isn't a cork float so it's newer I double check the point on the idle needle I do know I can't get it idle low enough that the Idle needle doesn't affect how it runs to much....would a compressed boss gasket affect it? Like I said when putting the bowl on there is no pressure from the boss gasket.

 

[Crosbyman]

A I recall...The boss gasket is for the high speed cct of the carb

as suggested you may want to clean out the low speed chamber with the 3 small drip holes of the low speed cct on the carb.

​did you carb clean the side channel feeding the upper chamber and blow it out with compressed air

when replacing the carb bowl gasket make certain the side channel passage is not covered up and you are using the proper gasket

​ if the needle (LS) has no effect on performance minimal gas is still gas is reaching the engine to keep it going make certain that needle is ok and the needle point actual extends into the upper idle chamber if/when you decide to clean it out. Otherwise blow in some carb cleaner in the LS needle channel till you can it it drip down the3 small hole above/behind the throttle pale

 

[lindy46]

You need to check the low speed needle and low speed orifice. Make sure the orifice is not chipped/broken. The only way to check it is to remove the plug.