donkeylips
Well-known member
I'm looking for a good check valve to put inline with my PCV valve.
The specifications I'm interested in are:
1. Pressure rating
2. Vacuum Rating
3. Opening(cracking) pressure
4. Temperature range
Here are a few that I'm looking at:
US Plastic 3/8" Kynar - #64175
1. 1psi-150psi
2. 2inHg - 29inHg
3. .5psi
4. Not listed
Price: $1.28
RTM Racing Plastic Check Valve (8mm)
No technical specifications given. Appears to be the same as above.
Price: $3.03
McMaster-Carr #7775K53 Quick-Opening Brass Check Valve
McMaster-Carr #5670K83 Stainless Steel Adapter
1. 1,000psi max. @ 70 deg. F (275psi max. @ 72 deg. F Adapter
2. Not listed
3. .3psi
4. +10 to +400 deg. F (-20 to +750 deg. F Adapter)
Price: $22.33 + (2ea. Adapter @ $4.47) = $31.27
Does anybody have any long-term experience with these? The only reason I'm considering the brass McMaster valve is because it has the lowest opening pressure and is good at high temps. Although it does get below 10 deg. F here in Buffalo.
My main concern is the opening pressure. How much pressure is required for the stock PCV valve to open? Can one of these check valves impede flow?
Or am I worrying about nothing when all of the check valves seem to open at 1psi or less? What kind of pressure is normal in the crankcase?
The specifications I'm interested in are:
1. Pressure rating
2. Vacuum Rating
3. Opening(cracking) pressure
4. Temperature range
Here are a few that I'm looking at:
US Plastic 3/8" Kynar - #64175
1. 1psi-150psi
2. 2inHg - 29inHg
3. .5psi
4. Not listed
Price: $1.28
RTM Racing Plastic Check Valve (8mm)
No technical specifications given. Appears to be the same as above.
Price: $3.03
McMaster-Carr #7775K53 Quick-Opening Brass Check Valve
McMaster-Carr #5670K83 Stainless Steel Adapter
1. 1,000psi max. @ 70 deg. F (275psi max. @ 72 deg. F Adapter
2. Not listed
3. .3psi
4. +10 to +400 deg. F (-20 to +750 deg. F Adapter)
Price: $22.33 + (2ea. Adapter @ $4.47) = $31.27
Does anybody have any long-term experience with these? The only reason I'm considering the brass McMaster valve is because it has the lowest opening pressure and is good at high temps. Although it does get below 10 deg. F here in Buffalo.
My main concern is the opening pressure. How much pressure is required for the stock PCV valve to open? Can one of these check valves impede flow?
Or am I worrying about nothing when all of the check valves seem to open at 1psi or less? What kind of pressure is normal in the crankcase?