Evinrude 48 SPL pulses when on plane

I have had this engine for a while on my 16' Stratos and overall it has run great. I had the carb. cleaned last fall (2007) and it has been doing good until recently. I can run at trolling speeds with no problem, but when I am on plane the engine pulses like it's running out of gas. This doesn't happen all the time, but I would say about 60% of the time. I used to have to pump the bulb and that would help, but recently the bulb became compressed and there was no way to even give it a squeeze. At the same time I made sure the vent was open to allow the vaccum to pull gas, but the bulb was still compressed. I feel like the engine is running great, there just seems to be a delivery problem. I am new to this awesome forum and any information is greatly appreciated.

Re: Evinrude 48 SPL pulses when on plane

Your primer bulb and/or fule line may be sucking air causing it to collapse. If it is old or possibly dry rotted it is cheap to change out.

Re: Evinrude 48 SPL pulses when on plane

The ignition could also be cutting in, and out. First! a compression test.

Re: Evinrude 48 SPL pulses when on plane

I just purchased a new fuel line assembly today. I will replace it as soon as the rain clears. Thanks for the advice and I will keep you posted.

Re: Evinrude 48 SPL pulses when on plane

Your engine is leaning out. NOT good.

Your bulb should never collapse. That is a sure sign of a fuel restriction.

If you have a built in fuel tank, I would bet your anti siphon valve is sticking.

That valve is located at the outlet of your tank.

Re: Evinrude 48 SPL pulses when on plane

DJ,
My tank is not built in. I use a simple 6 gal. tank with a screw vent at the cap. Can you explain leaning out? The bulb collapses when I am running on plane and it doesn't happen every time. Thanks for the reply - Brett

Re: Evinrude 48 SPL pulses when on plane

I'm betting your new hose set is going to help a lot. If not, try a different tank. Could be a restriction somewhere in the pickup tube. If this is a plastic tank, they're cheap enough.

Re: Evinrude 48 SPL pulses when on plane

The new hose did the trick! Only a $23 fix!!! Thank you all

Re: Evinrude 48 SPL pulses when on plane

Cut the old fuel barb apart, you will probably find a check valve in pieces'.

Re: Evinrude 48 SPL pulses when on plane

Cheers mate!