Rx Catch Can hissing sound

[ssmike]

For those of you with the Rx Catch Can, is it normal to hear a pretty loud hissing sound coming from the hoses to the catch can. Sounds like a vacuum leak. It is definatly the sounds of the gasses moving through the hoses in and out of the catch can. The sound goes away if I open the drain petcock but of course you can't drive it that way and it defeats the purpose. So with it closed and under normal operating conditions and engine is warmed up the hissing can be quite loud.

SC2150 says "if properly installed you should not hear any abnormal noise or sound". I double checked the install and I definatly have the hoses hooked up properly. I also removed the valve fitting and installed a non-valve fitting that he sent to me, no difference. Please advise!

[IndeedSS1]

Originally Posted by ssmike

For those of you with the Rx Catch Can, is it normal to hear a pretty loud hissing sound coming from the hoses to the catch can. Sounds like a vacuum leak. It is definatly the sounds of the gasses moving through the hoses in and out of the catch can. The sound goes away if I open the drain petcock but of course you can't drive it that way and it defeats the purpose. So with it closed and under normal operating conditions and engine is warmed up the hissing can be quite loud.

SC2150 says "if properly installed you should not hear any abnormal noise or sound". I double checked the install and I definatly have the hoses hooked up properly. I also removed the valve fitting and installed a non-valve fitting that he sent to me, no difference. Please advise!

I've not gotten around to putting my catch can back on after installing the straight through fitting. It seems odd that it would make that hissing sound with the new fitting. Perhaps the can is simply amplifying the normal sounds.

Mine other setup didn't do this and I'm wondering if filtering through the stainless mesh stopped it?

[ssmike]

I don't think it's the can itself but the hoses! I can grab ahold of the hoses and make the hissing change pitch and if I squeeze either one (pinched closed) the hissing stops cause I'm stopping the gas flowing in the hoses. Lee, if you get a chance can you try yours? Mine doesn't start hissing untill after the engine is warmed up if that helps!

[67motorcat]

Mine does the same as you describe.Thought it was a vacum leak also.

Nope,it's all good.I pinched the hose and the sound went away leading me to believe it is just the high vacuum at idle going through the orafices inside the can.

Maybe the sound gets amplified.So to answer your question I don't know if it's normal.
I can say though it works very well trapping oil.I'm not really worried about it.

[TAPSHIFT]

I installed mine a couple of weeks ago along with the oil cap/breather and it is also noisy, intermitantly. Hooked up correctly and even clamped the ends, which isn't even necessary apparently.

[IndeedSS1]

Originally Posted by ssmike

I don't think it's the can itself but the hoses! I can grab ahold of the hoses and make the hissing change pitch and if I squeeze either one (pinched closed) the hissing stops cause I'm stopping the gas flowing in the hoses. Lee, if you get a chance can you try yours? Mine doesn't start hissing untill after the engine is warmed up if that helps!

I've ordered some parts to make quick disconnects for the hoses. Looks like they were delivered today. Honestly though, I had decided to leave the can off. I'm almost to a burnout point messing with it. I'll see what I can do.

[mekc57]

Make sure the valve at the bottom is closed! I think those have to be turned all the way OUT to close them.

[mekc57]

I saw another post about this a while back and that was the fix. Mine is being shipped so I can't personally atest to this being the problem. I think the valve works like a radiator drain though.

[nancygrl]

I had the hissing. I carefully pushed the hoses a litte further onto the 2 fittings and mine stopped, thankfully!!!

[ssmike]

My drain valve is colsed and hoses all the way on! The earlier thread was about this same issue and I thought the drain was open so I thought I closed it and the hissing went away. Problem was that now it was really open. I discovered it when I removed the can and blew into the input and felt air come out of the drain. So, I re-installed it, closed the drain and HISS! If this ends up to be normal I'm pulling it out and returning it! It is quite loud and can be heard with the hood closed and idling and is very annoying. It really irritates me when you install a performance mod and it makes noise, or squeeks, or hisses, or causes another problem!

[TAPSHIFT]

Just got back from a short run and my can is making quite a racket. It is not a hiss, it sounds more like a dry bearing turning. Perhaps it is the check value vibrating??? Like one of the previous members, I too am not impressed. You can hear the noise in and outside of the car while running. Hoses are all tight, in the right fittings and the drain valve is turned out all the way out (closed). I will be sending SC2150 a PM as he has not chimed in on this most recent thread.

[mekc57]

Yeah, I ordered one, they said it's on it's way. If this is the way it is going to run, It's not even getting opened. It's going back!!!!!

They told me yesterday that there moving to a bigger shop right now and are bussy moving. Hope they reply to this problem!!!!! SOOOOON

[mekc57]

Has anyone tried unscrewing the fittings and wrapping them with tephlon tape? That might help? Just a thought.

I sent them a PM to respond to this thred!

[L99SS]

There were no leaks, hissing, or rattling following the install of my RX catch can. It's been on a few thousand miles now, and still no abnormal sounds from under the hood.

Just another thought, I don't have the breather cap. If you have one, try running without it (replace w/ OEM oil cap of course!) and see if the problem continues.