6 horse '73 Evinrude won't start

[paul becker]

Motor quit while running. Would only run when the choke was pulled out. Now it won't start at all. Taken apart carb. and inspected for clogs. It's clean. Changed gas and oil to new. Still won't run. Any suggestions on what to do next? Thanks!

 

[tashasdaddy]

Re: 6 horse '73 Evinrude won't start

did you do all this, you don't need special tools because you have adjustable jets. http://forums.iboats.com/showthread.php?t=244013

http://forums.iboats.com/showthread.php?t=167352

 

[paul becker]

Re: 6 horse '73 Evinrude won't start

I have tried all of the listed solutions still not running. the motor will burn a prime (fuel placed in the carb.) I am mystified. Pb

 

[F_R]

Re: 6 horse '73 Evinrude won't start

According to the parts list it has an orfice plug (fixed high speed jet). IF your problem is truly in the carburetor, I would almost bet the family jewels that you haven't removed and cleaned that orfice plug. All of the fuel that the motor burns passes through that precision calibrated orfice.

If it actually is clean, consider the possibility that the problem is not in the carburetor at all. What is your compression readings? How about the ignition? Will it jump a 1/4" spark gap?

 

[JB]

Re: 6 horse '73 Evinrude won't start

The first thing you need to do is find out what is wrong.

Changing, cleaning or overhauling stuff without knowledge that it needs changing, cleaning or overhauling is a waste of time and money.

I agree with F R that you probably failed to adequately clean the carb, but none of us KNOW that the carb needs cleaning.

Go to the Engine FAQs and do the "Outboard won't start" troubleshooting. Then you should KNOW that the carb is or is not the trouble.

 

[jay_merrill]

Re: 6 horse '73 Evinrude won't start

As usual, JB and FR have very good suggestions. I agree, start with the basics - fuel and spark.

I like to start with spark because it is so easy to confirm as being present or not in these engines. That said, the fact that the motor will run if you spray some premix in the carb suggests a fuel problem. Don't forget that, while junk in the carb is very often the problem, fuel delivery can be an issue too. Check to make sure that the fuel pump is working and check for an open fuel tank vent, etc.

 

[paul becker]

Re: 6 horse '73 Evinrude won't start

Jay, thanks for your thoughts. I have a quality spark in both plugs. The fuel pump will move fuel when I pull the starter, it pulses fuel. What, if anything can I do to test the fuel pump? Fuel vent is open. Each time I take the Carb. off the bowl is full of fuel. The bulb in the fuel line is hard and I know that fuel is reaching the the carb. inlet valve. I have inspected the high speed jet and found no clog. This carb. looks new. I am stumped

 

[F_R]

Re: 6 horse '73 Evinrude won't start

'tain't the carb then. Isn't the fuel pump either, If the carb is full of gas, it should run even if you took the fuel pump clear off the motor. At least for awhile till the bowl runs dry.

You are looking right at the problem and can't see it. Unfortunatly, all we can do from here is guess.

No, gol' dang it, on second thought, you say it will run if you squirt gas in it. HAS to be the carb, by all reasonable thinking. Please describe this high speed jet to us. Exactly what does it look like? What is the number stamped on it?

 

[JB]

Re: 6 horse '73 Evinrude won't start

Visual inspection is never adequate to determine that a carb is clean. The most critical passages cannot be seen. They must be cleared by mechanical or pneumatic means.

 

[jay_merrill]

Re: 6 horse '73 Evinrude won't start

At this point, my recommendation is to invest a few dollars in a carb rebuild kit. When you take the carb apart, be sure to remove the expansion plug (part #306442, item #10 on the 1973 ERude carburetor diagram, at www.shop.evinrude.com) in the top of the carb. If there is dirt in the associated passageway, you often can't get it out unless you remove the plug.

 

[paul becker]

Re: 6 horse '73 Evinrude won't start

I am about out of options. The carb has been blown out with air, soaked over night. The carb kit is my next step. Thanks for all the help. P. becker

 

[paul becker]

Re: 6 horse '73 Evinrude won't start

The high speed jet is located at the bottom of the bowl. The large screw is first removed and the jet can be cleaned out. I found no gum or crud in the orifice.

 

[F_R]

Re: 6 horse '73 Evinrude won't start

OK, forgive me for doubting you. I needed to be convinced that you found it.

 

[samo_ott]

Re: 6 horse '73 Evinrude won't start

Hmmm... this is a good one. Sounds like everything has been done... Interesting. I have one like this also now but will start another post

 

[paul becker]

Re: 6 horse '73 Evinrude won't start

Well I got her runnin. The carb kit was used. I also bought some benzine carb soak and let it sit for three days. Runs well at idle speed. Thanks for all the help. It really was the ticket to success.