Made by Monkeys

Bad PCV Valve Takes Driver on Rough Ride

View Comments: Newest First|Oldest First|Threaded View
Page 1/3  >  >>
User Rank
Re: Replacement Cost
DVanditmars   5/8/2015 3:27:11 PM
Just to clarify ;-)

"more likely some pointy haired management moron had this wonderful idea on how to increase profit"

User Rank
Toyota with similar problem
gmelton   9/5/2014 11:12:09 AM
Had the engine in my Toyota Corolla remanufactured.  The valve cover has a baffle that is not removable so a new expensive cover is required (so they thought).  The baffle is held in place by flattening a portion of the cover so that it takes the shape of a rivet.  Lowered fabricatin cost but is worthless for maintainence to remove the sludge buildup hidden behnd.  No amount of soaking or flushing removes the mess.  I machined off the fastener heads (grinding would also work) and removed the baffle.  Cleaned all the sludge then drilled and tapped the posts for 8-32 screws.  Reinstalled the gasket with aviation Permatex. Followed by the baffle. installed the screws with high strength Loctite and job completed.  It might have been easier to buy a new valve cover but I refuse to support poor design.  As for the Mini-Cooper.  I would have removed the old PCV and installed an in-line veerson. The world seems to be full of engineers who in fact are monkeys driven by the bean counters trying to save a penny.

User Rank
Re: Auto transmission failures and "permanent fluids"
Amclaussen   8/26/2014 4:59:16 PM
Well said laramsey, to expect the automatic transmission on a average sized sedan to last several years WITHOUT ANY MAINTENANCE (ATF replacement and Flushing) is quite unrealistic (and a very stupid design!).

Present day auto transmissions are heavily loaded thanks to ever present pressure to keep vehicle weight down, cost down, fuel efficiency high; and blindly believing in "marvelous modern fluids" that simply fail to produce those "magical", quasi eternal performance is Wishful Thinking.

FACT: all ATF's degrade after many thousand miles of heavy work.  That is the main reason why transmissions fail.  Not only wear products from the clutch packs and bands, are kept inside the transmission wearing parts, but metal particles themselves act as catalizers accelerating the fluid degradation by oxidation, thermal breakdown and sludge formation. Transmission fluid oxidation is unavoidable unless the system is hermetically sealed and filled with an inert gas cushion above the liquid level... I doubt the BMW transmission is not vented. All venting arrangements allow some degree of air  (thus Oxygen) ingress into the case. Long molecular chains characteristic of ATF's are unavoidably subject to breakage, producing "ligher ends", molecules that have a lower molecular weight and are prone to evaporate from the rest of the fluid, while  some other chains tend to polymerize and form "Heavy ends", that form heavier and heavier compounds that increase viscosity and form thick deposits or residues. It is only a matter of time, and the heavy deposits will plug the fine passages that are present in the valve body and solenoids. Sludge deposits are "cooked" on hotter transmission spots. Even the torque converter blades loose some efficiency as they loose their clean and smooth surfaces, which produces increased turbulence and more heat, in a vicious cycle. Pretending that an ATF fluid will be good "for the entire life of the car" is a blatant lie.

Maybe, an overly "creative" design manager at BMW, saw some highly optimistic and glamorized Synthetic ATF brochures, and immediately saw the opportunity to be "creative" himself, and used the (dis)information to pretend that the "Very Advanced BMW engineering" now can spare or make unnecessary the ATF change!

Don't forget monkeys not only work at BMW, but at Exxon-Mobil, Pennzoil, Quaker or Valvoline too! even when engineers at all those fluid companies could do an excellent job, the "creative" writers at their advertizing departments usually transform their recommendations into outreageous claims.

A proper, COMPLETE fluid replacement plus flushing is the best way to maintain the transmission in good order.  At least every 30,000 miles or sooner in dusty or heavy duty conditions. Please remember that draining the ATF's pan only removes about half of the entire contents of the transmission, thus a proper flush is needed to displace the entirety of the torque converter contents.  That can be done by connecting transparent vinyl hoses to the ATF outlet going to the cooler and returning, and having ready at least 30% of extra ATF bottles in order to start the engine in PARK and allow the transmission pump to displace the old fluid out at the same time (and rate) the new fluid is poured into the transmission, never letting the fluid level go down or above the proper level. When 80% or so of the old fluid has been displaced out of the transmission, you will see a dramatic change in color, but continue flushing with 4 or 5 extra quarts to be completely sure all the old fluid is out.

With a little care and practice, it guarantees more than 95% of the fluid is replaced, which is MUCH better than just replacing the pan contents.

During the fluid replacement procedure, it is best to clean all metallic shavings from the magnet inside the pan, and to replace the ATF filter and O-Ring.  Using a inside-motor cleaner (like Wynn's Oil system Cleaner) before removing the old fluid is an easy way to clean small hydraulic passages and valve orifices and flow restrictors. Just let it act at idle while shifting  manually from Reverse, Neutral, Drive, 2, 1 and back for 5 minutes (don't drive the car while the cleaner is inside the transmission!). Good luck with maintaining your transmission.

User Rank
PCV valve - Ugly strategy, but effective
laramsey   8/26/2014 11:56:20 AM
Welcome to one of BMW / Mini's revenue anhancement program.  And -  it gets worse.  I owned a 323, which needed more or less constant electric window repair, among other non-performance related items.  I couldn't find any aftermarket window regulator.  I asked the dealer if, after six plus years of production, had they improved the window regulator they were selling me for hundreds of dollars each.  The dealer unashamedly replied, and I quote:  "They are the same [parts] as always.  See all these cars lined up out here for service, including new ones?  Many of them will get window regulators.  They are basically the same as yours".  I pressed further, and uncovered what I suppose is the corporate line, and I quote:  "globalization" had reduced their options on window regulator suppliers to one, and "most all the car makers have about the same thing" installed.  He couldn't explain why many other makes have no such recurring problem.  The real reason it that as a manufacturer, with a good marketing strategy, you can easily prepetrate such things on an uneducated (from a technical/engineering standpoint) customer base.  

By the way, I maintained that car by the book, and it was a total loss at 11 years / 100k miles, because the "SEALED, MAINTENANCE FREE" automatic transmission failed.  So I'm out - that's the last BMW product I'll *ever* have.  In the end, I spent more on that car in most years, than I did on my Honda Accord in the *entire 17 years*  I owned it.

I only wish I could say BMW was the only manufaturer that does things like this.

User Rank
Re: Replacement Cost
dbell5   8/26/2014 10:31:45 AM
@zeeglen: "some management moron had this wonderful idea"

Not just Desiged by Monkeys, but worthy of a Dilbert strip...

User Rank
Re: ifixit
tekochip   8/26/2014 8:12:49 AM
It depends upon the design, of course, but PCV valves do wear out.  I had a Mustang with a carburated engine and I used to clean the PCV valve rather than replace it.  After well over 100K miles the car began to run poorly and it took me the longest time to realize that plastic body of the PCV was horribly worn.

Of course the replacement was only a few of bucks not hundreds.

User Rank
Replacement Cost
zeeglen   8/25/2014 7:01:17 PM
...but I'm sure he wasn't thinking about replacement cost.

I must disagree with the author on this point - I'm sure the engineer really was thinking about the replacement cost.  Not necessarily liking the idea, more likely some management moron had this wonderful idea on how to increase profit from parts sales that only they could provide.  And then forced the engineer to design it accordingly.

Larry M
User Rank
Re: ifixit
Larry M   8/25/2014 3:34:57 PM
EV Professor wrote "I would never pay $400 for a valve cover. I would spray the PCV valve with solvent and blow it out with shop air and schedule it to be cleaned every 50,000 miles."

Exactly what I was thinking. These valves don't fail; they just sludge up. I can't remember how many dozen I dumped into a coffee can with a few inches of gasoline, at various times back in the 1960s and 70s. After a soak of several minutes, a good swishing back and forth until sludge stopped coming out, and then a final blow-out/suck out was all it took.

Obviously this valve cover would take something a little bigger than a coffee can, but even if you had to buy an aluminum foil throwaway roasting pan and a gallon of gasoline (or safer solvent), you would still be way ahead.

User Rank
Old cars
Cadman-LT   8/20/2014 10:08:03 AM
GTOlover, I love your solution...buy old cars!

User Rank
Re: A group of Greater Monkeys of the worst class!
patb2009   8/12/2014 7:56:48 PM
that's what i was thinking, use a utility knife to cut out the

old PCV valve body, and then get an in-line PCV valve of any reasonable size.



Page 1/3  >  >>
Partner Zone
More Blogs from Made by Monkeys
Made By Monkeys highlights products that somehow slipped by the QC cops.
One reader had to dismantle the Mazda Tribute for the sake of changing the alternator and some spark plugs.
Made By Monkeys highlights products that somehow slipped by the QC cops.
Made By Monkeys highlights products that somehow slipped by the QC cops.
Made By Monkeys highlights products that somehow slipped by the QC cops.
Quick Poll
The Continuing Education Center offers engineers an entirely new way to get the education they need to formulate next-generation solutions.
Oct 10 - 14, Embedded System Design Techniques™: Getting Started Developing Professional Embedded Software
SEMESTERS: 1  |  2  |  3  |  4  |  5  |  6 |  7 | 8 | 9 | 10

Focus on Fundamentals consists of 45-minute on-line classes that cover a host of technologies. You learn without leaving the comfort of your desk. All classes are taught by subject-matter experts and all are archived. So if you can't attend live, attend at your convenience.
Next Course September 27-29:
Sponsored by 3M
Learn More   |   Login   |   Archived Classes
Twitter Feed
Design News Twitter Feed
Like Us on Facebook

Technology Marketplace

Copyright © 2016 UBM Canon, A UBM company, All rights reserved. Privacy Policy | Terms of Service