PAIR Reed Valve as Crankcase Vent?

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landtoy80

landtoy80

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Is there anything inside the PAIR reed valve that will melt or get plugged if I route the gasses from the crankcase to the intake of the PAIR reed valve or would I be better off just tapping into the steel line and put a "T" on it?
This is assuming that the PAIR system has vacuum? I would think so as there is no pump on the system that I can see and air gets sucked in.

If possible, I would just rig up the PAIR so that its always open. This would be easier than removing the pipe and putting a "T" in the pipe.

I know that I would have to unplug the O2's as they would give a false signal from the blowby gasses. I have run with O2's with no harm for thousands of miles.
 
Took apart the PAIR valve and it will work. It has a back fire valve in it and all metal inside except for a rubber gasket.
Did a mock hooked it worked. Used vacuum to open PAIR valve and I got vacuum in the crankcase. Its very little at idle but goes up with rpm's.
I hooked the vent valve of the valve cover to the PAIR valve and hooked up the vacuum gauge to the PCV valve port.
I will be putting the vacuum gauge in the cab to monitor the vacuum in the crankcase when driving. If there gets to be too much vacuum I will get a vacuum relief valve.

This should resolve my positive pressure in the crankcase. Should keep my oil from getting degraded and thinned with blowby gasses and stop the leaks from the excessive pressure. I hope :D
 
FAIL.

The PAIR valve has vacuum at idle and if you rev the motor when parked. Has pressure when driving then spikes of vacuum.
Was hoping that is would be like an E-Vac Scanenger but its not.
 
Vented to atmosphere under hood with no catch can and it stunk so bad could hardly breath.
Would a catch eliminate that much smell?

I so far have vented under hood, stinks all the time.
Vent to the cats. Use the old rear heat line to get there. Cut the steel line where it entered the cab and vented there, stunk when I stopped.
Just tonight I added 3' hose from where the steel line is and ran the hose to the running board under rear pass side door. Drove a few miles and no smell yet. Will get more hose to exit at rear bumper.
Not sure how that much hose will affect venting the crankcase?
 
An hose venting open is not going to work so well if you are trying to relieve pressure in your crank case. You need to hook the hose back to intake manifold with an oil catch can and NO PCV valve. The vacuum from the intake manifold will suck out the blow by better than venting to the atmosphere.

The reason I said no PCV valve is to have an unobstructed flow of crankcase gases as it gets sucked out by the intake manifold vacuum.
 
I thought about doing what you said than wondered if that would affect air fuel mixture. From what I have been reading, the PCV valve meters the flow of blowby gasses. Wouldn't the flow rate be too much for the ECU to compensate for with on unmetered PCV valve.

From Positive Crankcase Ventilation (PCV)
PCV PROBLEMS



The most common problem that afflicts PCV systems is a plugged up PCV valve. An accumulation of fuel and oil varnish deposits and/or sludge inside the valve can restrict or even block the flow of vapors through the valve. A restricted or plugged PCV valve cannot pull moisture and blowby vapors out of the crankcase. This can cause engine-damaging sludge to form, and a backup of pressure that may force oil to leak past gaskets and seals. The loss of airflow through the valve can also cause the air/fuel mixture to run richer than normal, increasing fuel consumption and emissions. The same thing can happen if the pintle inside the PCV valve sticks shut.

If the pintle inside the PCV valve sticks open, or the spring breaks, the PCV valve may flow too much air and lean out the idle mixture. This may cause a rough idle, hard starting and/or lean misfire (which increases emissions and wastes fuel). The same thing can happen if the hose that connects the valve to the throttle body, carburetor or intake manifold pulls loose, cracks, or leaks. A loose or leaky hose allows "un-metered" air to enter the engine and upset the fuel mixture, especially at idle where the idle mixture is most sensitive to vacuum leaks.

On late model vehicles with computer engine controls, the engine management system will detect any changes in the air/fuel mixture and compensate by increasing or decreasing short term and long term fuel trim (STFT and LTFT). Small corrections cause no problems, but large corrections (more than 10 to 15 points negative or positive) will typically set a lean or rich DTC and turn on the MIL.

Problems can also occur if someone installs the wrong PCV valve for the application. As we said earlier, the flow rate of the PCV valve is calibrated for a specific engine application. Two valves that appear to be identical on the outside (same diameter and hose fittings) may have different pintle valves and springs inside, giving them very different flow rates. A PCV valve that flows too much air will lean the air/fuel mixture, while one that flows too little will richen the mixture and increase the risk of sludge buildup in the crankcase.

Watch out for cheap replacement PCV valves. They may not flow the same as the OEM PCV valve. Quality brand name replacement PCV valves are calibrated exactly the same as the original valves, and are designed to provide long-lasting, trouble-free performance.
 
Was thinking of using one catch can with 3 ports (like the breather catch can) and hook up the pcv valve to catch can to suck up most of the blowby and run the vent line under vehicle. That way only the excess blowby will be vented to atmosphere.

Or use 2 catch cans. One can for the pcv system (stock configuration) where it is still sucked into the intake and other can hooked to the vent port so that any excess pressure/gasses will just vent to under vehicle.

Trying to make it the least stinky as possible.

2 catch cans vented under vehicle is the easiest way to go if it doesn't stink.
 
Vented under the vehicle you won't smell anything. Here is an example on one of my other vehicles. Dual catch can set up. PCV valve eliminated with a straight through open fitting. The clear silicone hoses are from the 2 vc ports. The 2 black silicone hoses are the exit and routed under the vehicle. No mess. Only fumes can escape the catch can. Any oil stays inside because of it's internal design. Or just replace your rings.

78bac4b5_a391_42f3_94f4_66c0bd1c0ac8_1.jpg
 
Yesterday: I changed the oil. Drive 50 mi today with no smell at all. I bought a new PCV valve and hooked it up this after noon and left the vent port open to atmosphere to relieve excess pressure. Drove 50 more miles and no smell.

With the new PCV valve hooked up and a plastic bag on the vent port of the valve cover, I started the motor. The plastic bag filled up instantly at high idle. When motor dropped to normal idle the bag would fill up slowly but when I rev the motor it filled up instantly. This confirms that I have excess pressure in the crankcase.

Now that the excess blowby gasses can escape, hopefully the issues of pressure in the crankcase (diluted oil, stinky oil, seeping seals) will be reduced. With fresh oil, there is no issue of stinky oil vapor. Now I just need to make or buy a catch can to catch oil oil vapor. Thinking of using a small ammo can as a catch can. Prior to venting, my oil pan was the catch can where all the unburnt fuel, blowby gasses and oil vapor just condensated and fell to the pan.

I should of looked into this problem about 100,000 mi ago when I noticed that the PCV hoses and oil fill cap were seeping oil. I just ordered a new filler cap and put hose clamps on the hoses. That is when I noticed that my oil consumption when up and I started to use additives to deal with it.
 
I would like to end this thread as its not really related to the thread title, not using the Reed valve to vent crankcase.

After about 700 mi of venting to atmosphere along with the PCV valve hooked up, the crankcase no longer has pressure. After about 600 mi, the hose/pipe that I hooked up to the vent port that runs to the rear bumper was accumulating fluid somewhere. So I mocked up a catch can. Its spaghetti sauce glass jar that I installed two ports on the lid and put a scouring pad inside as a baffle. After 96 mi there was just a little clear fluid in the jar, no oil yet. The oil level has not gone down yet. I usually dont have to add my first qt of oil till 1800 mi, its gets progressively wore at the oil get diluted. Will see what happens now that the crankcase can vent away the moisture.
 
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4G63 POWER said:
Wow you just don't want to spend any $ do you.
Click to expand...
Wanting to and having money to are two different things. I am at the later right now. I was lucky to be able to spend $20 (tax return came in) to buy the hose to vent crankcase to the rear bumper. This $1.49 gal gas is killing me! MORE POWER TO OPEC !!!!
BUT:
On my defense, had I had the money, I still would be doing the same thing but with parts from Napa rather than from O'Reily and the dumpster.


I am at the point in my life where I dont need to spend money to fix things...
jun18755-jpg.190553

ok, I have been there before...
 
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