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-   -   If you ever cut open a PCV valve (https://www.offshoreonly.com/forums/general-q/334220-if-you-ever-cut-open-pcv-valve.html)

bck 02-01-2016 05:34 PM

If you ever cut open a PCV valve
 
3 Attachment(s)
I don't know why all this weirdness always happens to me but I figured this might save someone some trouble.
I had someone work on the boat/engines and one of the things he said he routinely did was install pcv valves but he takes the check balls out. So he proceeds to buy 4 new valves, gut them and install them. Well before I actually stated the engines for the first time I had occasion to remove the valves and I see a round piece of metal laying on my rocker arm. Just complete luck that I happened to remove the valve and that it landed directly on a damn rocker and was visible. I had a hard time getting a good pic but there is an extra piece of metal (like a double thickness for reinforcement) up at the top of the valve that can fall out.

Keith Atlanta 02-01-2016 05:38 PM

How the heck does it work without the check ball? Doesnt that defeat the purpouse?

bck 02-01-2016 05:42 PM

I have no clue. Maybe to have it flow better? I trusted him and let him do his job. I mostly learned what not to do.

bck 02-01-2016 05:49 PM

By the way. For those who followed the " what do these bearings tell you" thread, this was not the same person. This happened later in the game of take all my money.

getrdunn 02-01-2016 07:57 PM

Be thankful you caught the ball. Hard to say what the outcome would be if you hadn't. I've seen some things in the bottom of pans that baffle me to this day. Some that didn't take the path of least resistance that's for sure. I've never used pvc valves in marine however have seen them and from what I've heard is merc has gone back to using them. Probably more so to do with environment-issues than that of any real reason for them. But it's ok to spray hazardous chemtrails down on us everyday. Lol. Evidently your engine guy don't see the need for them however the only thing I would imagine he's doing by removing the ball is to utilize the pvc body as an oil trap. I'm not sure of what your running engine wise etc but regardless good catch.

Btw you may want to confirm he has the other three balls in his possession???

Good luck

mike tkach 02-01-2016 08:09 PM

without the check ball the valve is nothing more than a vacuum leak.did he say why he does this?

Black Baja 02-01-2016 08:23 PM


Originally Posted by mike tkach (Post 4399472)
without the check ball the valve is nothing more than a vacuum leak.did he say why he does this?

More like an oil siphon.

mike tkach 02-01-2016 08:25 PM


Originally Posted by Black Baja (Post 4399477)
More like an oil siphon.

lets just call it a detonation monster!

bck 02-01-2016 08:45 PM

They were gutted and empty. You wouldn't notice the extra layer of metal up inside unless you looked very closely. You can see in the pics how hard it is to tell which one is missing. The other valves still had this piece intact. It ended up being a non issue as the engines have been taken apart.I guess the pcvs were used because the engines had the provisions for them. As far as why the insides were removed, I have no idea. This was a reputable builder with an established business, not a side job. He just said that's the way he does it. The other end of the hoses was hooked up to the nipple on the flame arrestor.

SB 02-01-2016 08:54 PM


Originally Posted by bck (Post 4399491)
They were gutted and empty. The other end of the hoses was hooked up to the nipple on the flame arrestor.

That's how Merc does it on most of their motors. If you kept theirs, they are empty and nothing to gut.

Anytime you see a factory motor with tubes going to the arrestor, the PCV looking things are not actually PCV valves, because they are hollow inside with no springs/balls.

Issue is when people think these are supposed to be PCV valves,

PCV valves are not open to atmosphere, they are connected to full intake vacuum.

Very common for people to get confused on these, until they have been there and done that.


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