70Hp Johnson Not Starting

[win222]

Hello all,

On one of my boats, I have a 1997 70Hp Johnson outboard, about 3 years ago, it would no longer start.

I have no clue how to work on outboards, so I took the top off, and wondered what the problem could be?

The only thing I seen inside there that I could move was a red level, so i decided to turn it, and somehow magically the boat started right up, lol.

So for the past 3 years, I have been pulling the top off, and hitting this lever, which I found out is the fuel primer solenoid or it's bypass, the motor starts right up, then dies, I then have to flip the switch back, re-start it and it runs great all day.

Now that I have some $, I want to fix the problem, is the problem the fuel primer solenoid is bad? or could it be the primer bulb on the fuel lines? The primer bulb is really old and hard, I can barely squeeze it any more?

I'm going to replace the primer bulb either way.

Thanks!

[BassHunter954]

Clean intake system an rebuild throughly clean it really good.

[Catt]

I have a 1996 Johnson 70, change the fuel primer solenoid & primer bulb

[win222]

I changed the primer bulb today and the fuel lines from the tank to the motor, took forever to prime it, had to pump it about 200 times, but then the motor started right up, without messing with the solenoid.

I'll have to let it sit a full day now, to see if it starts without messing with the solenoid.

[Way2slow]

It's easy enough to check the primer solenoid to see if it's working or not. Pump the primer bulb up until it's firm, while holding some pressure on the primer after getting it firm, (not extreme pressure or you can push the needles off the seats and make it leak down) have someone turn the key on and push in on it to activate the primer. The bulb should start going soft fairly quickly if the solenoid is working.

You do understand the primer only works while the engine is turning over. The engine has to be spinning for the fuel pump to be working and the fuel pump has to be pumping to pump fuel through the primer solenoid to prime the engine when the key is pressed in.

Now, what I have seen is a weak battery or one that does not have enough cranking amps (or bad connections) the solenoid will not energize when cranking because the starter is pulling the voltage down too low. A way to check this is to crank the motor for a couple of seconds to build up fuel pressure, quit cranking and immediately press the key, do this three or four times quickly and then see if it starts. If your electronics cut off when you crank the motor, you can just about bet the solenoid is not energizing also.