PCV has whistle and/or whine

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crewchief

A & P Mechanic
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On my third valve now. Every PCV I have used last for a short time (500 miles) before it begins to produce a whine noise.
It doesn't matter whether it's an OEM one or aftermarket.
Any insight?
 
Is your PCV in your valve cover? Is the valve cover baffled?

You may be sucking more oil through the PCV than they’re intended for, which is fouling the PCV. It’s also worth noting that not all PCV’s pull the same amount of vacuum, some pull more than others and pulling too much can pull oil too.

I run a HV oil pump on my 340, and it throws a lot of oil around even at the rockers. I baffled my Cal Custom valve covers, then used a 1/2” spacer to raise the valve covers further from the rockers, then finally relocated the PCV from the valve cover to the top of a catch can (there’s a pick up in the valve cover that runs to the bottom of the catch can). I also tried several different PCV’s to tailor the amount of vacuum being pulled through the system. There is a PCV valve that can be tuned, although it’s pretty pricey for a PCV.

Bottom line is it may take some trial and error to get the PCV system set up so it works for your engine.
 
Totally agree^^^!


Not a science, I know of and some experimenting may be required. For me it was only 2 to find the right balance. The pricey adjustable saves the trying but! Baffles are important in the long run.
 
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Is your PCV in your valve cover? Is the valve cover baffled?

You may be sucking more oil through the PCV than they’re intended for, which is fouling the PCV. It’s also worth noting that not all PCV’s pull the same amount of vacuum, some pull more than others and pulling too much can pull oil too.

I run a HV oil pump on my 340, and it throws a lot of oil around even at the rockers. I baffled my Cal Custom valve covers, then used a 1/2” spacer to raise the valve covers further from the rockers, then finally relocated the PCV from the valve cover to the top of a catch can (there’s a pick up in the valve cover that runs to the bottom of the catch can). I also tried several different PCV’s to tailor the amount of vacuum being pulled through the system. There is a PCV valve that can be tuned, although it’s pretty pricey for a PCV.

Bottom line is it may take some trial and error to get the PCV system set up so it works for your engine.
Yes, valve is in the cover and it's baffled. I'm using a HV pump too which as you say "throws a lot of oil around. Just need to find the PCV that can work.
 
I bought a PCV like this

Summit Racing® PCV Valves SUM-440308

Reason being they can be taken apart and the spring swapped out. Find an Ace hardware with a good spring selection and you can make your own adjustable valve. Takes longer but it’s a ton less money than the adjustable one.

But even after that I ended up buying one of these. I got the PCV set up right, but it still pulled too much oil

Trick Flow® PCV Air/Oil Separators TFS-51400850

I plumbed it with this and some AN like to the valve cover. Spent a crap load anyway. Although the fancy adjustable PCV would have still needed it on my car

Trick Flow® Oil Vapor Line Limiting Breather Fittings TFS-51400861
 
You might would like to give this a try. I have one on my magnum 408 with HV oil pump.

M/E WAGNER

yup, that’s exactly the $130 adjustable PCV I was talking about. Couple bucks worth of springs and the one I posted earlier works too. :D

and yes I realize I spent more than that on a catch can. But when PCV was right it still pulled too much oil at the valve cover, so it got moved.
 
yup, that’s exactly the $130 adjustable PCV I was talking about. Couple bucks worth of springs and the one I posted earlier works too. :D

and yes I realize I spent more than that on a catch can. But when PCV was right it still pulled too much oil at the valve cover, so it got moved.

How did you make it dual flow like the M/E Wagner?
 
How did you make it dual flow like the M/E Wagner?

Didn’t, doesn’t need to be.

I get it, the Wagner is a really nice PCV valve. But most engines don’t use anything like it.

And really the PCV wasn’t the problem I was having, it was too much oil flying around. I needed the PCV pulling what it was pulling, just without the oil. Moving the PCV out of the cover solved the issue.
 
You might would like to give this a try. I have one on my magnum 408 with HV oil pump.

M/E WAGNER
I tried stock PCV and my engine caused intermittent clacking and whining. Installed the Wagner PCV valve and multiple good things happened and no more noise. My Cal Custom valve covers are baffled and stood off the heads with spacers as well. Didn't stop the noise issue though until I changed the PCV valve.
 
I tried stock PCV and my engine caused intermittent clacking and whining. Installed the Wagner PCV valve and multiple good things happened and no more noise. My Cal Custom valve covers are baffled and stood off the heads with spacers as well. Didn't stop the noise issue though until I changed the PCV valve.

The only issue I was really having was the amount of oil I was pulling. I did foul a stock style PCV early on, but when I went to the aftermarket PCV’s that wasn’t a big issue. I was pulling oil into the carb though. I went to lower vacuum PCV’s, but ended up with crankcase pressure pushing gases out of my vent. Setting the PCV to pull what it needed pulled oil too. Relocating the PCV with a vapor separator solved the issue. The adjustable PCV is nice, but it wouldn’t have solved the issue I was having.

Whether or not it will solve the OP’s issue I don’t know, just sharing my experience to give him something to check.
 
Try a Standard Motor V165 pcv. Typically not an in stock item, you'll have to order it online. I had an 85 D150 w/318 and the valves from all the parts stores whistled. The Standard version didn't.
 
Opps doesn't show the one I had in mine. This one comes in 3 different hose sizes.

Precision Flow-Adjustment Valves with Barbed Fittings for Chemicals
3010n12p1-c03a-digitals.png


  • Valve Type: Needle
  • For Use With: Water, Oil, Air, Argon, Butane, Carbon Dioxide, Citric Acid, Deionized Water, Diesel Fuel, Ethanol, Ethylene Glycol, Gasoline, Helium, Hydrochloric Acid, Isopropyl Alcohol, Kerosene, Krypton, Methanol, Mineral Spirits, Natural Gas, Neon, Nitric Acid, Nitrogen, Oxygen, Phosphoric Acid, Propane, Salt Water, Soap Solutions, Sodium Hydroxide, Sodium Hypochlorite, Sulfuric Acid, Toluene, Xenon, Xylene
  • Seal Material: PTFE Plastic
  • Packing Material: PTFE Plastic
  • Needle Material: PVDF Plastic
Barbs grip onto tubing, providing a secure hold. To withstand aggressive and corrosive solutions in chemical-processing applications, these valves have a PTFE seal and a PVDF body. Turn the handle to adjust flow in small increments for metering, sampling, and other applications requiring fine flow control. Threads and a hex nut below the handle allow you to install these valves in instrument panels. They have a nut that can be tightened to compress the packing if it leaks.

For
Tube ID For Tube
OD Max. Pressure Max.
Temperature, °F Panel
Cutout Dia. End-to-End
Lg. Each
Black PVDF Plastic Body
Barbed × Barbed

1/4" 3/8" 125 psi @ 140° F 140° 7/8" 3 5/16" 3010N11 $24.65
3/8" 1/2" 125 psi @ 140° F 140° 7/8" 3 5/16" 3010N12 24.65
1/2" 5/8" 125 psi @ 140° F 140° 7/8" 3 5/16" 3010N13 24.65
 
The OP says that he is having problems with a whine/whistle stating he has tried different traditional PVCs with no luck. I suggested the M/E Wagner because it's made differently than a normal PVC. My thinking it would solve the whine/whistle because it's fully adjustable to work on any engine without having to piece something together. I've found that most of the time but not always I have to get out the wallet to fix issues with these engines..lol

Hard to tell what is really causing the whistle not knowing the specifics. Like how much vacuum the engine has at idle? Does it whistle at idle, cruise or all the time?
 
The OP says that he is having problems with a whine/whistle stating he has tried different traditional PVCs with no luck. I suggested the M/E Wagner because it's made differently than a normal PVC. My thinking it would solve the whine/whistle because it's fully adjustable to work on any engine without having to piece something together. I've found that most of the time but not always I have to get out the wallet to fix issues with these engines..lol

Hard to tell what is really causing the whistle not knowing the specifics. Like how much vacuum the engine has at idle? Does it whistle at idle, cruise or all the time?
Vac is at 15/16 @ idle. Only begins to make noise once in gear and cruising.
 
Try a Standard Motor V165 pcv. Typically not an in stock item, you'll have to order it online. I had an 85 D150 w/318 and the valves from all the parts stores whistled. The Standard version didn't.
The last one I used was a V165, but it didn't stay quiet for too long. Lasted about 300 miles.
 
Are you sure it is not the air cleaner or something around the air horn on the carb? That is a common area for 'whistles' and squeaks. Try just taking the air cleaner off and put it back on and see if the whistle goes away for a while.
 
Are you sure it is not the air cleaner or something around the air horn on the carb? That is a common area for 'whistles' and squeaks. Try just taking the air cleaner off and put it back on and see if the whistle goes away for a while.
Used a stethoscope to narrow it down. It's the pcv, replace it and all goes quiet for awhile. It's the oddest thing to last only for a short period of time.
Hose is new and routed to rear a carb base. Noisy with air cleaner off.
 
So if you used a stethoscope that was at idle..... and at a higher vacuum level than at cruise. You probably know this: the PCV has a low flow and high flow setting that varies with vacuum. If you are using a stock Mopar replacement, then they seem to open from low to high flow at around 13-14 in vacuum. So it almost seems to be whistling at both flow settings: at higher vacuum/low flow at idle for your stethescope test, and then at medium vacuum/high flow settings when cruising.

That seems to point to the connections on the PVC rather than the internals where the variable valve is. So no hose collapsing? Are you using proper PCV hose that is made to resist collapsing under vacuum conditions?

Not sure this helps....
 
So if you used a stethoscope that was at idle..... and at a higher vacuum level than at cruise. You probably know this: the PCV has a low flow and high flow setting that varies with vacuum. If you are using a stock Mopar replacement, then they seem to open from low to high flow at around 13-14 in vacuum. So it almost seems to be whistling at both flow settings: at higher vacuum/low flow at idle for your stethescope test, and then at medium vacuum/high flow settings when cruising.

That seems to point to the connections on the PVC rather than the internals where the variable valve is. So no hose collapsing? Are you using proper PCV hose that is made to resist collapsing under vacuum conditions?

Not sure this helps....
Yes, it's a thick wall hose, no collapsing on any part of the hose and connections are tight. The valve has chatter which tells me that it is opening and closing rapidly. At idle, no sound of a whistle, it begins as soon as you put it into drive from park.
 
Have you replaced the rubber grommet in your valve cover? They are notorious for drying out and shrinking even if they look fine visually. A new PCV valve will seal for awhile then once she gets a little oil around her which does not take long will start moving around in worn out grommet. Went thru whistle/whine pcv issues on my 65 cuda & after several pcv valve replacements finally replaced rubber grommet on my valve cover with new softer rubber one that sealed nicely and no more issues.
 
Yes, it's a thick wall hose, no collapsing on any part of the hose and connections are tight. The valve has chatter which tells me that it is opening and closing rapidly. At idle, no sound of a whistle, it begins as soon as you put it into drive from park.
Sounds like a mild cam and the vacuum pulses are causing the PCV valve to chatter between high and low flow settings. So it probably is right on the edge all the time.

One suggestion is to the switch to a certain MP PCV valve, which changes from low to high flow at a lower vacuum level. I can never keep track of the MP PN.....
 
The OP says that he is having problems with a whine/whistle stating he has tried different traditional PVCs with no luck. I suggested the M/E Wagner because it's made differently than a normal PVC. My thinking it would solve the whine/whistle because it's fully adjustable to work on any engine without having to piece something together. I've found that most of the time but not always I have to get out the wallet to fix issues with these engines..lol

I agree. I only suggested the $25 valve as a tool to tinker with flow to see if it goes away with a little less flow. I didn't mean as a permanent fix as I should of stated.With all the valves he's bought now he could have the one you suggested. I hope the grommet fixes your issue. It sounds very plausible.
 
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