PCV Valve Replacement Questions

A little more thinking here too: I'd be inclined to use Loctite 242 (blue), a more easily removable product, regardless of Toyota's recommendation to use a more permanent thread lock. Per @StarCaller:

PCV Valve Replacement Questions | PriusChat

 

well, now you know both methods but I agree, if you're going to clean the intake, the pcv is there for easy access. If you just want to replace it if its causing the issue, then going from the bottom is easier to replace, unless you want to remove the intake manifold...

 

I'm likely going to remove, clean reinstall my pcv valve in the next few days, in conjunction with a replumb of my oil catch can. Taking the intake manifold off too, give it a clean out.

I'm thinking now for the pcv valve: a few turns of teflon tape.

I've had it out before, about 2 years back, didn't apply any sealant, and the zone around and under is a little grubby.

 

The new PCV valve I have in my garage has something already applied, which I'm assuming is either a sealer or a thread lock, is that not standard?

I'm doing this as well (intake/pcv/occ), hopefully this weekend.

Do you guys do anything to the MAP? I'm going to fully remove the throttle body, pinching off the hoses and taking the MAP off, should I just leave it alone, or if it's oily do I clean it (understanding that it's sensitive)?

 

The stuff on the new PCV valve is probably the Repair Manual spec'd thread-lock (see attached). FWIW, when I removed the PCV valve on ours it wasn't too hard, so I'd likely just screw it in, as-is. I believe it's equiv to Loctite 271? Loctite 242 has also been mentioned, as effective and a little easier to remove, down the road.

You're taking off the throttle body to facilitate taking off the intake manifold? And maybe clean the throttle body? For either of those two tasks, I'd recommend to just unbolt the throttle body and lift it off, but leave the coolant lines attached. There's enough play that you can move it out of the way, clean it if you like, and tie it to the inverter, just to make room for intake manifold removal.

The MAP (Manifold Absolute Pressure) sensor, just below and to the right of the throttle body: yeah I would remove and clean it. I sprayed it with MAF (Mass Air Flow) Sensor cleaner (CRC brand), and gently brushed with Q-tip.

 

I'll try that, I thought I would give myself more room for the OCC install on the bottom beam but I guess I probably won't need that much.

 

If you're screwing or bolting to the bottom beam, for a bracket, put some sort of rubber gasket or washer in between the bracket and the beam. The beam needs to flex, when you're using the front jacking point (it's the underside of that beam.

I used through bolts when I connected to the lower beam, fished them through openings on the underside of the beam, but it was very awkward. If I was doing it again think I would just drill pilot holes, then use some self-tapping screws. Again, put some sort of compressible gasket in the "sandwich".

Anyway, what I did was through bolt from below, then a rubber washer on top, then my bracket, then a steel washer, then a nut snugged down, and finally a second nut, torqued against the first, while restraining the first nut from turning. This gives you a bolted connection that will not come loose, but has some give.

Another trick is rivnuts or rivstuds.

Or even better: just some heavy-duty zip-ties wrapped around the beam, to secure a bracket? Avoid drilling in it.

 

Another take:

DIY: How to Replace the Positive Crankcase Ventilation Valve (PCV) On Your 3rd Gen Prius » Balancing Act

 

Dealer parts guy said they don't stock PCVs since they never need replacing. Is there a way to test the valve? Did anyone have one that had failed?

 

They have them in Sarasota...and on the east coast...

 

There's a fair bit of bs and cryptic description in the attachment. There is a description how to test it.

Just do what you have to do to get to it, remove the valve with a 22 mm socket, give it a good shot of Carb Cleaner. I cleaned the threads, applied a little Permatex 243 thread lock, and torqued to 15 ft/lb.

If you want to replace it's under $10, shouldn't be too hard to get.

=================================================
PCV valve p/n: 12204-37010
Connector hose between pcv valve and intake manifold:
HOSE, VENTILATION p/n: 12261-37060
=================================================

 

Thanks for that. Low cost to replace, but the test looks easy to do. I suppose if I take it out I may as well put a new one in.

 

Maybe should mention, Permatex 243 is not spec'd threadlock, just easily available. I think the object is mainly to prevent it leaking, and a thread lock will do that. The 243 is a relatively easy-to-remove threadlock, and description says it's still effective if threads are a bit oily. It's just what I used recently.

Maybe the new ones come with the kosher threadlock on the threads?

Also, you could skip the thread lock, it'll likely just get a bit grubby directly below.

The 243 does gum up the threads a bit.

 

I bought my PCV valves from a dealer parts store, and they were Aisin brand parts (just like the ones I removed). They came with dried green goop already on the threads. So no additional threadlocker necessary on those.

 

So I just replaced my PCV valve and I might have made a mistake. I dont have an adaptor to fit my 22mm socket onto my 3/8 torque wrench (the 22mm socket is 1/2 inch drive). So I used the 1/2 inch drive wrench I have to tighten it down fairly tight and just tried to take a guess at what 15 ft/lbs feels like (i have recent memory of this tightness when I did my spark plugs) but I avoided really wrenching on it as 15 ft/lb isnt much.

I was thinking that I'd order an adaptor set so I can get my 3/8 torque wrench attached to my 1/2 inch drive socket and then tighten to 15 ft/lbs, but I am not realizing that if I do that I risk breaking the factory sealant/thread locking material (looks like it has a curing time of 24 hours, that will be past by the time i get the adapter), and then I'd have to reapply the thread sealant. Any advice? Do you think "kindof tight" with a ratchet is good enough, or if its not tight enough do I risk it leaking through the threads? Its one of those situations where I am 50% worried I overtightened it and might be stripping it, and 50% worried its too loose and might leak.

Maybe that means its good enough? Or maybe i should bite the bullet and buy some blue thread lock, remove the pcv valve, apply thread lock and then torque to spec?

 

One more thing. Here are some specs from a ToyotaNation post (cant verify accuracy) about the Three Bond:

THREE BOND 1344,
Break loose torque 50-70 kgf.cm, prevailing torque 50-70 kgf.cm
blue, 600CPS, low strength, med viscosity, frequently removed, 300F max
cure: initial 1-2h, final 24h

According to Toyota equivalent to LOCTITE 242
McMaster Carr 91458A112 $12.71 Loctite 242 Threadlocker Adhesive,10ml, 0.34 oz, Blue, 300F

Superior to (450F) LOCTITE 246
McMaster Carr 91458A480 $14.50 Loctite 246 Threadlocker Adhesive, 10ml, 0.34 oz, Blue, 450F


THREE BOND 1324
Break loose torque 100-150 kgf.cm, prevailing torque 250-300 kgf.cm
red, 600CPS , med strength med viscosity, removable, 300F max
cure: initial 1-2h, final 24h

According to Toyota equivalent to LOCTITE 271
McMaster Carr 91458A160 $12.71 Loctite 271 Threadlocker Adhesive, 10ml, 0.34 oz, Red, 300F

Superior (to 450F) LOCTITE 266
McMaster Carr 91458A570 $14.50 Loctite 266 Threadlocker Adhesive, 10ml, 0.34 oz, Rust, 450F

 

I think the thread lock is mostly considered a thread sealant, and I don’t think it’d hurt to back it off and retorque.