MDX PCV valve design

[artbuc]

Not at all familiar with this design. It does not click when you shake it although it works when you apply air pressure. Seems like the spring is so strong it does not let the piston move when you shake the valve. Dealer says a good working valve will click but whoever got good info from a dealer? Is anyone out there familiar with this type of PCV valve? Thanks.

http://www.partsgeek.com/catalog/2010/acura/mdx/air_intake/pcv_valve.html

 

[Hokiefyd]

You should be able to hear it rattle, though I do concede that it's pretty faint. This is the same PCV valve design used on all Honda J-series V-6 engines. Both of mine rattle a bit when you shake them, but it's faint. They tend to not get all that fouled up. You can spray it out with parts cleaner, but they're not very expensive to begin with, so it's probably worth it to just replace it.

 

[Trav]

+ 1 Standard Honda J engine PCV, it will rattle when shook if its any good. When these foul sludge, deposits and possible oil use are not far behind.
Its a pizz poor design that's way too small for this engine.

 

[artbuc]

Thanks for the responses. I got it as clean as possible. Used almost a full can of carb cleaner. Got a lot of crud at first but then the cleaner came out clean. Guess there is enough residual crud to resist the spring. New one on order. Reason I took a look-see is because I am burning oil...1 qt per 5k for the last 10k.

 

[Trav]

The one from Advance Auto is aftermarket boxed but contains an original Honda part in the OE Honda bag.

 

[Hokiefyd]

Originally Posted By: Trav
The one from Advance Auto is aftermarket boxed but contains an original Honda part in the OE Honda bag.


Good to know, thx.

 

[benjamming]

Originally Posted By: artbuc
Thanks for the responses. I got it as clean as possible. Used almost a full can of carb cleaner. Got a lot of crud at first but then the cleaner came out clean. Guess there is enough residual crud to resist the spring. New one on order. Reason I took a look-see is because I am burning oil...1 qt per 5k for the last 10k.


BTW, 1qt/5k miles is no cause for concern. I assume that this was an uptick in usage though.

 

[HangFire]

Originally Posted By: Trav
+ 1 Standard Honda J engine PCV, it will rattle when shook if its any good. When these foul sludge, deposits and possible oil use are not far behind.
Its a pizz poor design that's way too small for this engine.


It's huge and typically lasts 100K miles, but it's a pizz poor design and too small?

Disclosure: I have a Pilot (J35) and replaced the original at 120K and it improved nothing because there was nothing wrong with the old one.

 

[rcy]

I changed the one in my 2006 MDX at 180 000 km, and it still rattled, just not as easily as the new one I put in. Interesting to note that Honda does not list the pcv valve as a maintenance item. It is huge compared the pcv valve on my 2004 Maxima.

 

[Trav]

Whats huge about it? Most of it is the long plastic body, the business end is tiny.
Take another look at the valve carefully.

 

[Georgiey22]

Have a 2013 TL and have never replaced the PCV on this J35 3.5L engine. Does anyone have an image of where the PCV is on the J35? Want to get familiar with its location, I like to proactively change my PCV's at 75K miles since the maintanence cost is affordable and usually simple to complete.

 

[artbuc]

Originally Posted By: Georgiey22
Have a 2013 TL and have never replaced the PCV on this J35 3.5L engine. Does anyone have an image of where the PCV is on the J35? Want to get familiar with its location, I like to proactively change my PCV's at 75K miles since the maintanence cost is affordable and usually simple to complete.


Here you go:

http://www.paulstravelpictures.com/Honda-Pilot-V6-Engine-PCV-Valve-Replacement-Guide/index.html


Lube the orings before installing. Be careful that the bolt bushing (Honda calls it a collar) does not fall out as you remove the old valve. It is easy to see the valve but not easy to get your fingers on it.

 

[rcy]

Originally Posted By: Trav
Whats huge about it? Most of it is the long plastic body, the business end is tiny.
Take another look at the valve carefully.


Yeah, I see what you're saying. The tapered end is the actual valve. Seeing as it doesn't connect to a hose, like most other PCV valves, I wonder if that accounts for the design? Honda has used this design on their 6 cylinder for some time - I can't imagine that it doesn't work.

 

[Hokiefyd]

It connects to the hose (though indirectly) that runs up to the intake manifold or the top plate (I've never seen one that runs directly to the top plate, as in that Honda Pilot pictorial linked above). The OP's MDX's PCV valve is on the transmission side of the cylinder head, which is apparently an improvement over the original design that our '05 MDX has, where the PCV valve is at the crank snout side of the cylinder head, right underneath the dipstick area. Our Ridgeline also has it on the transmission side of the head, so Honda has moved it to that side on all of their more recent J35 engines.

I call it an "improvement" only because they changed it. I can't imagine them making a change without a good reason for it.

 

[rcy]

What I mean by it doesn't connect to a hose, is that it doesn't fit into a rubber hose like a lot of other pcv valves. It looks like it blocks the hose or pipe inlet but doesn't actually fit inside.

 

[Hokiefyd]

Oh, right...it's an internal channel in the cylinder head cover that conveys the crankcase gasses to the silicone hose (then on to the intake manifold). The PCV valve seals to that channel with the small o-ring at the end of the valve.

It does seem to work. I'm not sure how one would know if the PCV system is "big enough" or not. I do know folks who have installed catch cans on their Honda V-6s get some sludge in them, so it's certainly passing the gasses though. And I'd guess the evidence of a valve that's too small would be a build-up of junk in the front cylinder head cover area, and I'm not sure Honda V-6s have a history of that (VCM issues aside).

Trav -- how do we know the valve is too small?

 

[Trav]

It works but the system they had on the older engine was much better, they had a large opening PCV in the rear cover. The ones near the dipstick on VCM engines had a habit of clogging once deposits started building up.
They moved it to the rear of the front cover as a band aid. Once the small holes got plugged up it's all over.

Front PCV side.

Rear.

 

[artbuc]

Originally Posted By: Trav
It works but the system they had on the older engine was much better, they had a large opening PCV in the rear cover. The ones near the dipstick on VCM engines had a habit of clogging once deposits started building up.
They moved it to the rear of the front cover as a band aid. Once the small holes got plugged up it's all over.

Front PCV side.

Rear.

Been wrenching on my (and many friends') cars for 50 years and never ran into a PCV valve that could not be cleaned or had to be replaced as PM. If my oil consumption is caused by a fouled PCV valve, I will start replacing it every 30k miles. Not a big deal but certainly not what I would expect from an Acura. Hopefully I do not have a separate problem which is causing oil consumption and fouling the PCV valve.

Been using Pennzoil 5w-20 dino. Would I get less sludge with synthetic?

 

[Trav]

If its a VCM engine then yes you would be much better running synthetic without extending the OCI.

 

[slacktide_bitog]

At least the PCV is on the front valve cover!