Easy question, I hope! Johnson 70hp 2000

[salud]

Hey ya'll...just got a boat with this motor on it.

About a month ago, I had a 5 year maintenance done to the motor by a neighbor who works in a good shop up the street.
The motor was running great...purring.

THEN, I installed a water sperating fuel filter between the built-in fuel tank and the motor. Now it is still running but it does not idle well at all and it will stall. Sometimes after it has run and then you stop, it has trouble cranking again...I have figured that if you prime the bulb it will crank better.

Alot of times when I am idling and might need quick power, I have to shift-lock it into neutral and rev up the RPMs to keep it running.

It is almost like the fuel filter has made it hard for the pump inside the motor to pull fuel through it.

I also read something somewhere else on this forum about the anti-siphon valve but I am not sure how to go about problem-solving this as I am new to motors.

Can anyone help me through the steps?
I would greatly appreciate it as this condition makes it hard to throw the net on the poles while baiting shrimp!!

 

[tashasdaddy]

Re: Easy question, I hope! Johnson 70hp 2000

do you have the proper micron filter for your motor. you may have one for an inboard/outboard, which has a much stronger fuel pump. or the filter may be clogging, due to crap picked up.

 

[salud]

Re: Easy question, I hope! Johnson 70hp 2000

Hey thanks for the speedy reply there, tashasdaddy!

Pretty sure the micron filter is the right one...a guy I know and really trust just replaced all that stuff.
All the filters are brand-new so there "shouldn't" be any crap in them.

Like I said, I think it has to be connected that the motor was running fine one day. The next day I install the water separating fuel filter, go out, and this problem begins.

Any more thoughts?

 

[1730V]

Re: Easy question, I hope! Johnson 70hp 2000

Tashasdaddy may be correct.

If the primer bulb pumping helps, you are starving for fuel. You may also have an air leak that has developed with the installation of the filter. Recheck your hose connections.

The anti siphon valve is at the outlet of your fuel tank. It is part of the hose barb that is the outlet. Typically, when the valve sticks, your engine will suck the primer bulb flat.

Also, check your primer bulb. It has an arrow on it showing the direction of fuel flow. The arrow should be pointing at the engine. Don't ask me how I know that one.

 

[salud]

Re: Easy question, I hope! Johnson 70hp 2000

I was doing some research at another location and already double-checked the hose connections. In fact, the initial installation I did with cable-ties and I went back and replaced those with S/S hose clamps. So hopefully I eliminated the air leak.

You think I should check the anti-siphon valve? I don't understand why it is running at higher RPMs just fine. Maybe I should clean that valve anyway.

I had another friend suggest that the new filter might have messed with the idle adjustment. However, I have no clue how to adjust that...I have an idea how to do it, the general idea, but have never done it.

The primer bulb and the arrow I will double-check but I think that is one of those things you just grow up knowing and I didn't mess with the side going to the engine. Never hurts to look.

Clean the anti-siphon valve?

Thanks again for all the input, the message board is one of the most active and informative I have ever come across.
Let me know what you think.

 

[1730V]

Re: Easy question, I hope! Johnson 70hp 2000

Your idle fuel needle valves are accesible behind the air silencer. Your model may have rubber plugs, on the front, that can be removed to access the idle richness screws. There would be three in a line, up to down. If not, remove the face of the air silencer.

As a general rule, set them this way.

1. GENTLY seat each one by turning all the way in. Emphasize-GENTLY.

2. Turn each one out 1 and 1/2 turns to start.

3. Adjust in/out from there.

4. This procedure needs to be done in the water or with the engine in a barrel. You can't do it, on the muffs. The engine needs backpressure to get the adjustments correct.

 

[salud]

Re: Easy question, I hope! Johnson 70hp 2000

Hey man, that is exactly what my friend was telling me
about adjusting in the water and backpressure is the term he used.
I told him that with the ears on it idled perfectly.
It all makes sense.

How hard is it to get to the air silencer? Is it a real tricky procedure?
This friend made it sound like you might need some special tools for this (he didn't say this maybe implied or I read into it).
Unfortunately I do not have any of the manuals for the engine. I was planning on getting them this winter.
Do you have any general diagrams or is there anything else you can explain?

Also is it a good idea to seat them, then adjust OR can you adjust the way they are already set?

Thanks!

 

[GreatRiverDucker]

Re: Easy question, I hope! Johnson 70hp 2000

The air silencer is right in front of the carb, it should be a straight forward adjustment.