0392988 Check-Valve question?

[rothfm]

Ok, Read the posts on these little intake manifold one-way check valves.....

before forking over $20+ each X 4......Really want to know if mine are bad. Broke one during a rebuild-took em all out for testing.

I have spares from other motors but they also seem about the same. They will emit a tiny amout of air, if I blow really, really hard thru them--in the correct "screen-to-Nipple" direction, and nothing in reverse. SO, the one-way check seems to be working. But it seems it takes too much pressure to get any air to pass. I soaked them, with the same results.

IS THAT NORMAL? Meaning it takes ALOT of pressure to get a tiny tiny bit of air to come out????. I Know the factory manual says to use a syringe and alcohol-with "light pressure"-dont have a syringe at the moment.

Should it be really hard to get air through?? I'm of the Camp that if the factory put them there, I want them in place and working, particullarly after a rebuild.

 

[motodave]

Hey rothfm, I just popped for 6 new ones, using my mouth I can barely push air thru screen side to nipple, can't push any thru nipple to screen side. It should be fairly hard to push thru but not that hard, if you can blow thru them at all and the screen is clean, and you soaked them id let them ride. It's just tiny pulses of fuel that if thru them. You can also check them while engine is running, pull hose of bypass cover and should have tiny pulses of fuel coming out. Hope this helps!

 

[rothfm]

Thanks MotoDave, Thats what I was looking for.

Yep, I can force a bit of air thru them with my mouth, its hard but a bit of air does come out- Nadda the reverse-way. I soaked a bunch of them and they all sorta react that way.. Guess I'll use 'em for now.

Thanks for the come-back.


MR

 

[motodave]

Glad to do it, I was on the fence about spending the money on them also, but all 6 of mine easily flowed alcohol both ways. Haven't run it yet but I will be back on here posting if it doesn't help the idle

 

[boobie]

The only proper way to check them is what the factory manual tells you. If they fail the test, replace them as they're part of the carb calibration.