Spark Arrestor, Anti-Siphon Valve, and Carb tutorial?

[Les Welch]

I posted a thread a couple days back about some WOT bogging, getting up to speed issues I am having. I have a 5.0 Liter OMC Cobra drive, 230 HP. I took the spark arrestor off last night and the outside of the "filter" is quite black. Here are a couple of pics. You can see where I wiped it off with my hand, and where I didn't.

Here is one of the inside, untouched by me.

Couple of questions.

1) What causes the black buildup, is it burning fuel?
2) Is it normal to be this dirty? I have no idea when the PO last cleaned it.
3) How do I clean it? Soak in gas, blow off, air dry?
4) Could something this simple be causing my bogging, lack of getting up to speed?

 

[Les Welch]

Re: Spark Arrestor, Anti-Siphon Valve, and Carb tutorial?

I was also told to check the anti-siphon valve coming out of the tank. I have no idea what that is. Here is a pic of the gas tank.

The big hose on the left is the one for filling the tank. The hose on the left is the one that runs out to the fuel pump. The smaller one on the right side of the fill hose, I am unsure what does. Is this where the anti-siphon valve would be?

Sorry for all of the basic questions, this is my first boat, and I am not engine/motor smart. It is however a fun learning experience.

 

[Les Welch]

Re: Spark Arrestor, Anti-Siphon Valve, and Carb tutorial?

a pic of the carb

 

[Don S]

Re: Spark Arrestor, Anti-Siphon Valve, and Carb tutorial?

1) What causes the black buildup, is it burning fuel?
2) Is it normal to be this dirty? I have no idea when the PO last cleaned it.
3) How do I clean it? Soak in gas, blow off, air dry?
4) Could something this simple be causing my bogging, lack of getting up to speed?

Yes, it's normal. Oil and fumes from the valve cover is where the black comes from.
DO NOT use gas for parts cleaning. Diesel fuel is better, use a brush to clean the flame arrestor and blow it out with compressed air from the inside out.
It doesn't look near plugged up enough to be the problem.

The picture below shows where the anti-siphon valve is, and which hose does what.,

Here is how to test your boats fuel system.
http://forums.iboats.com/showthread.php?t=167561

 

[Les Welch]

Re: Spark Arrestor, Anti-Siphon Valve, and Carb tutorial?

Thanks Don, great link. I'll pick up a gauge tonight, but can't get on the water until next week.

What should I be looking for with the siphon valve? I assume I should take it apart, then is it something visual I should be looking for, or do I blow it out, or something else? Thanks

Les

 

[aries50hp]

Re: Spark Arrestor, Anti-Siphon Valve, and Carb tutorial?

anti-siphon valve has a spring and ball that lets fuel flow in one direction.had mine off yesterday due to old gas and years of neglect.(previous owner)man it was caked shut!

 

[Howard Sterndrive]

Re: Spark Arrestor, Anti-Siphon Valve, and Carb tutorial?

I had a boat where the engine cover sound deadening foam was rotting, fine dust would come off the foam and adhere to the oil film and clog the flame arrester. The fuzz I see in yours looks familiar.

 

[sw33ttooth]

Re: Spark Arrestor, Anti-Siphon Valve, and Carb tutorial?

also i had old belts on my engine that were putting off a lot of dust pulleys were kind of rusty so when i cleaned mine it looked a little worse then yours but wipes right off.
i would NOT use gas to clean the spark arestor when the engine backfires if it does this is the only thing keeping you from an explosion some compressed air or a rag and some brake cleaner or desiel whatever just not gas.

 

[Randy J]

Re: Spark Arrestor, Anti-Siphon Valve, and Carb tutorial?

no smoking but i use a can of either for cleaning spark arrestor and just let it set for a few min clean.. if have a odd or big lots store is cheap price. other wise auto parts store but truck stops are real proud of everything lolo. truck stop 4 miles town 15 miles...