Carb Rebuild on a '77 2cyl 55hp Evinrude

[glengold]

Took the carbs off today and noticed a hose not connected to anything on one end. It's under the bottom carb and the one end was connected to the block (see pic)

What is this hose for?? should it be connected to something??

Next I began disassembling the carbs and noticed several differences from the exploded view that came with the kits.

First the floats hang way more than 3/4" down, so they are obviously resting on the bottom of the bowl.

Next the low speed jet needle was all the way in, and the rebuild instructions say it should be one turn out. (could this cause my top carb to be running lean?)

Both carbs low speed jet needle were fully seated.

Lastly the fuel line goes from the fuel pump to the bottom of the top carb, then a fuel line goes from the side of the top carb to the side of the bottom carb. Then there is that "mystery hose" not connected to anything besides the block.

I'm not sure if I should put it back together they way it was or go by the directions that came with the kit. There is a disclaimer saying things may vary between motors, hopefully someone will have a better understanding of this motor.

 

[jtexas]

Re: Carb Rebuild on a '77 2cyl 55hp Evinrude

The mystery hose is there to scavenge the oil that collects on the inside of the air silencer cover; there will be a nipple on the airbox for it. It's not mission-critical, but left unconnected will allow a small amount of oil to drain into the lake, and the inside of your cowl to get all oily.

The carb-to-carb fuel supply routing is correct -- once the line is pressurized, both bowls will stay full.

On reassembly, adjust the float height with the carb held upside down -- it should hang parallel with the carb body. That will cause the valve to shut off when the bowl is full; with an empty bowl, it doesn't really matter how it hangs.

After reinstalling the carbs and completing the link & sync, adjust the low speed jets according to the instructions in the "joe reeves" thread in the "engine faq" section of iboats. They seem to be incorrect as they are now, but they'll be perfect once you get done with 'em.

You're doing fine so far, just check back with any questions.

 

[glengold]

Re: Carb Rebuild on a '77 2cyl 55hp Evinrude

thanks tex, that explains all the crud in the inside of the cowling.

The low speed jet is part # 38 Idle Orfice http://shop2.evinrude.com/Index.aspx?s1=j0om3u15krgu8fa4u7ln01pb57&catalog_id=0&siteid=1

I have to remove the Idle Passage screw plug to get to it right? while the motor is running....

Is that the first carb adjustment FAQ by Joe Reeves? One per carb I guess because the High Speed jet isn't accessible while the motor is running since its at the bottom of the bowl and would be full of gas

 

[glengold]

Re: Carb Rebuild on a '77 2cyl 55hp Evinrude

on second thought I think these are fixed jet. there is no needle, just the orfice.

so I guess fully seated then....

 

[glengold]

Re: Carb Rebuild on a '77 2cyl 55hp Evinrude

Anyone know if the idle orfice on these carbs needs to be all the way seated? There are three holes at the top of the throat for the idle fuel to enter, I am unsure if the idle orfice position changes the amount of fuel entering @ idle. Upon disassembly the orfices were fully seated.

She idled ok before but it could have been smoother...

 

[jtexas]

Re: Carb Rebuild on a '77 2cyl 55hp Evinrude

Yes, it should be in there tight.

Don't take a chance on mangling that soft brass with a regular screwdriver -- there's a special tool for use on those jets. To fabricate one out of a screwdriver using a dremel or belt sander, see this thread:
http://forums.iboats.com/showthread.php?t=244013

 

[glengold]

Re: Carb Rebuild on a '77 2cyl 55hp Evinrude

thanks jtexas for the reply

I had seen that thread and made the tool from an old screwdriver.

I was still worried about mangling the high speed jet bc it wouldn't budge with quite a bit of pressure so I just cleaned it w/a piece of wire in place.

Everything was pretty clean upon disassembly but in the process I found what I believe to be the culprit... One of the throttle plates was loose and wouldn't close all the way @ idle.

I wish I could go outside right now and test her out but Gainesville is about to get slammed by some serious weather.

 

[glengold]

Re: Carb Rebuild on a '77 2cyl 55hp Evinrude

I got the carbs on and she idles great, however, I found yet another problem which may be compromising my top speed....

When I was pumping up the ball to fill the carbs I could hear an air leak coming from the fuel line connector on the side of the cowl. Upon closer inspection there is a space between the connector and the motor when the clip is snapped in place.

I am assuming that a 1/4 inch rubber washer is supposed to go here to seal the connection.

Can anyone verify this for me? I was going to go to home depot and pick up some rubber washers but want to be sure I get the right thing, being that its around fuel.

Thanks for the help guys, my girlfriend thinks I'm addicted to messing w/my outboard.... And then I told her I've been scouting craigslist for a non-running small outboard to fix up for my canoe (flat-back). She just rolled her eyes!!!!!

 

[HighTrim]

Re: Carb Rebuild on a '77 2cyl 55hp Evinrude

Thanks for the help guys, my girlfriend thinks I'm addicted to messing w/my outboard.... And then I told her I've been scouting craigslist for a non-running small outboard to fix up for my canoe (flat-back). She just rolled her eyes!!!!!

I get that everytime a new outboard joins the rest of the family in the basement....apparently its not "fashionable" to have a QD16 beside the couch, go figure, I think its beeeautifullll.

 

[jtexas]

Re: Carb Rebuild on a '77 2cyl 55hp Evinrude

there's no washers there. the air-tight connection is formed inside the connecter.

there's an o-ring inside the female (hose-end) connector which is supposed to be replaceable, but for a couple bucks at walmart you can get a replacement connector.

I don't think I've ever had to replace a male connector (motor and tank), seems like its always the female that goes bad.

hey just wait till you tell her that outboards need to be taken out & run hard every couple-three weeks, to keep internal parts oiled up and carbs from accumulating varnish...........

[high trim: first she ditches the neon beer signs and now this? next she'll be wanting you to take the trohpy fish off the living room wall!]

 

[HighTrim]

Re: Carb Rebuild on a '77 2cyl 55hp Evinrude

[high trim: first she ditches the neon beer signs and now this? next she'll be wanting you to take the trohpy fish off the living room wall!]

Wait till she sees how I removed the legs on the dining room table and replaced them with golden javelins