suzuki 2001 70hp

[fshndad]

hello, just rebuilt the motor.

I started it up today idles fine but when i rev it up on the flusher it surges up and down.

I checked the fuel lines and followed the service manual.

any thing else i should check.i emptied out the fuel before puting it back together. new plugs. new fuel filter.

[karlow]

Likely fuel starvation.

Did you replace the filters?
Did you pull and clean the fuel/air separator?
The other thought is to place a pressure gauge between the mechanical pump and the fuel /air separator and check the pressure.

Here is a simple test, if you are squeezing the bulb will the surging stop?

KP

[fshndad]

filters were replaced back in July. and VST tank replaced same time. i emptied the tank before putting it back together

someone on another board said there is a rev limiter on those motors and does the same thing if on the ear muffs.

i didn't try squeezing when it's doing that. I'll try it again this week.

Thanks!

[karlow]

I tried that on mine the other day. It did not surge.
Two things, it did that before I repaired it. I am not reving it that high, maybe 1200 or 1500RPM.

I say fuel starvation, put a gauge on the fuel rail.

[fshndad]

i not sure but another guy on a different forum said it's normal it's the rev limiter.

it does it at about 2800 rpm. which sounds about right.

Karlow, do you have a 2001 and older 4 stroke motor? if so could you text me a picture or take a picture of the intake manifold side? i have a service manual for the 2002 johnson motor(brp told me only that model was available) and mine does not tell me were the intake manifold cover water hoses go.

[karlow]

My motor is a 2002. I have a pic, but I can't attache it because it is too large.
I would not operate the engine that high in RPM on the muffs or unloaded. It might be the rev limiter kicking in.

KP