evinrude light twin problem

[yorick]

Hello, I have an 1963 evinrude lightwin 3 hp (3302s). I just rebuilt the carb and I can get it to idle, but any additional throttle just kills it, and I get gas running out of the carb. I took the carb apart again and checked the float and it seems ok to me. Any ideas what I'm doing wrong ? thanks

 

[tashasdaddy]

Re: evinrude light twin problem

gas running out is sign that float needle is not seating, or float is not adjusted right.
http://forums.iboats.com/showthread.php?t=167352

 

[F_R]

Re: evinrude light twin problem

Did you put a new float valve in it? Sounds like that is the part that isn't doing it's job. Also, did you replace all the gaskets with new ones? How about the thick one that goes on the main nozzle in the center? The '63 has a fixed high speed orfice jet...did you take it out and clean it? It has a tiny hole in it that meters the fuel and must be absolutely clean.

 

[rolmops]

Re: evinrude light twin problem

Are you sure that the float actually floats? Or does it have a leak and does it sink?

 

[steelespike]

Re: evinrude light twin problem

I think you have two problems.The gas flooding is either the float valve not closing from some problem (dirt?)Float may be adjusted wrong.
With the carb inverted the normal top of float should be level with and even with the gasket surface of the carb body.With carb inverted you shouldn't be able to blow into the gas inlet.If it is a brass float shake it to see if gas has leaked in.if so get it out then solder the leak with solder gun.You can get the gas out by heating and cooling the float with a light bulb with the leak down to allow the gas out.BE VERY CAREFUL OF GAS FUMES WHEN DEALING WITH A CARB best to work in the open air.
If cork it may have absorbed gas and need to be dried out and sealed with epoxy.If adjusting the mixture screws doesn't solve the stalling then there is probably still gunk in the high speed passeges or jet.

 

[yorick]

Re: evinrude light twin problem

Thanks for the help,
I just took the carb off for a more carefull cleaning, the float is not cork or brass, but appears to be plastic, and it doesn't seem to be full of gas... I understandthat the high speed jet is in the bottem of the fuel bowl? How is it removed?

 

[tashasdaddy]

Re: evinrude light twin problem

special screw driver. it is behind the drain plug.

 

[yorick]

Re: evinrude light twin problem

thanks, Ill get out my grinder.

I live at 7000 feet up in the mountains, will the elevation cause me problems with the fixed jet?

 

[yorick]

Re: evinrude light twin problem

I removed the jet. Just how big is the hole in the jet supposed to be? I measure the hole in this jet to be 3/32 " which seems kind of big to me. Does anyone know what the proper size is supposed to be? thanks for the help.

 

[F_R]

Re: evinrude light twin problem

That is WAY too big for the orfice...unless you have the adjustable needle kit installed (???)

The orfice plug for motors without the adjustable needle kit is part number 309345. It was produced in two sizes, .029" and .030". If you order one, you will get the currently reccommended size.

 

[jameskb2]

Re: evinrude light twin problem

Good morning Yorick,

Before I found this great forum, I purchased a 1962 Evinrude Lightwin.

I didn't know diddly about 2 stroke outboards, but I did know a lot about automotive engines, and had repaired small 2 strokes like chainsaws and weed whackers. So...I dived in.

Your engine is considered by many to be one of the all time "classic" honeys. They run and last forever. This, provided that they receive proper care of course.

The site that explained everything to me, and walked me step by step through the tune up and tweak process is here:

Maxrules

Read through the parts that you are wanting to learn, then read the rest. I took an old cracked coil, burnt point, soaked cork float engine, and have it running like a top!

My best,

James

 

[yorick]

Re: evinrude light twin problem

OK, I ordered the new high speed jet, I get the feeling that it is the problem. The old one looks like someone drilled it out? It is the fixed jet, no high speed needle.
I checked the float, and I can't blow through it when carb is inverted, so that seems to be ok.

I thank everyone for their help.

James that is a great web site, thanks for the encouragment. This is my first outboard,but like you I have done some auto and two- stroke work before. I have to say that these things are much more fun to work on than a car!!