1981 70 hp turns over, but won't run

[bdmorningstar]

I have a 1981 70 hp outboard that I can't get to run. I replace the battery and just rebuilt the fuel pump. I also bought a new fuel lane from the tank to the motor. I noticed that the female end that hooks to the tank looks like it just has a rubber piece where the male at the motor pushes against it. My old female connection looks like there is a ball bearing that the male end pushed against to open up the fuel line. The new fuel line is 3/8", and I think the older one was smaller.

The motor turns over easily, but i can't get it to catch and run. It did for just seconds a couple of times before I rebuilt the fuel pump. I can't get it to catch and keep running. Any ideas? Could the new fuel line from the tank to the motor be bad?

Thanks for your help.

 

[mfkadz]

Have you ever seen the motor run?

Is gas getting to the bowls? The carbs on my 55 HP have bolts at the bottom front of each carb. You can loosen them up and see if there's gas there. You can drain them. Then pump on the bulb and put your head by the carbs. The bulb should squeeze easily at first and you should hear gas going into the bowls. Once full the bulb should be hard to squeeze.

Another test is to put a couple fingers over the carb intake and see if your fingers get wet when you crank it.



mike

 

[bdmorningstar]

Thanks Mike. There's fuel in the filter bowl, but the plugs aren't wet, and after i put the new diaphram in the fuel pump i took it apart again, and it was only partially damp in one area, and there was fuel smell in the lines coming off it, except for one. I bought a new fuel hose, and the bulb felt crunchy at first, which i thought was odd, and only pumped up hard once. I bought a pre-1998 hose set, but the female coupler to the motor looks like it has a small diaphram the male piece pushes against, rather than the steel ball my old one has. The next thing I'm going to check is for spark.

 

[mfkadz]

Sounds like the wrong fitting. Pumping once would pressurize the hose to the connector.

mike

 

[bdmorningstar]

Took the boat to a repair shop today and found out is was an electronics issue. That and a few bucks later and it's running again.

Thank you for the ideas.