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Backwards PCV Valve Broke My Car

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Tim
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Platinum
Bad luck
Tim   11/11/2011 12:41:21 PM
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The function of PCV valves is usually a no-brainer.  You lost on the luck of the draw on this one.  I am sure that Fram produced at least a million of these PCV valves.  If their part per million (PPM) defect rate was one, you got the unlucky one that failed miserably. 

herbissimus
User Rank
Silver
Re: Bad luck
herbissimus   11/14/2011 10:55:56 AM
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doesn't every mass produced product have an acceptable quality level? wouldn't that mean that  most every manufacturer determines, based on largely economic factors , what percentage of products will be d.o.a. or in some other way , less than perfect?

the guy that put his filter on with 2 rubber gaskets isn't alone, but several times the professional oil change guys have dangerously overfilled my crankcase, which also can be an engine killer.

i find myself wondering how many industrial processes when considered from end to end have so many open loops in them--places where there's no, or incomplete feedback, so quality suffers.

David McCollum
User Rank
Gold
Just lucky
David McCollum   11/13/2011 11:38:57 PM
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I'm guessing I've been lucky all these years. I always verify the things I can check, liking bloing both ways on a PCV valve, but who can see inside an oil filter.

averagejoe72677
User Rank
Gold
Re: Just lucky
averagejoe72677   11/14/2011 10:04:51 AM
I have been avoiding Fram products for many years. I bought a new Toyota Corolla in the mid 1980's and was warned by the dealer that I would void my warranty if I used a Fram oil filter. Fram had apparrently been producing oil filters without an anti-drainback valve. That engine had a high horizontal oil filter and without the anti-drainback valve, the oil filter would simply drain all the oil within it back to the oilpan, resulting in a momentary dry start each time the engine was started. Fram did correct that issue later on. The manager of a local parts store said the Fram Rep came in and replaced all their inventory  with updated filters that did have the anti drainback valve. I never did go back to the brand as reports started sufacing that the bean counters within Fram had cheapened up the product by cutting the amount of filter media in their oil filters. This is a shame as Fram used to be a top shelf product. I now use Purolator, Motorcraft and Wix. Better be safe than sorry.

 

David12345
User Rank
Platinum
Re: The devil is in the details
David12345   11/14/2011 10:24:42 AM
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 I had a similar experience to the split oil filter on a motorcycle, but it was my fault.

I changed the oil and filter on my 1983 Honda Shadow.  After refilling the crankcase to the proper level, there were no leaks and everything seemed fine.

It was a pretty day, so I took my wife to work on the back of the motorcycle.  As I entered one tight turn the back of the motorcycle got REAL squirrelly, but we successfully rode it out.  I immediately pulled over expecting a flat tire, but instead found an intact tire with an oil coating.  We made some calls and her girlfriend took her on to work.   I had a friend with a trailer get me and the bike home.

 The oil filter was right in front of the rear tire and had the rubber seal blow, dumping 1.5 quarts of oil on the rear tire in under 50 feet.  A little investigation revealed that the old oil seal had attached to the metal of the engine; so that, I had 2 seals doubled-up when I installed the new filter.  This was fine until the bike got fully warmed-up. Then with the higher oil pressure of operating at speed, the double-seal blew-out. 

Clearly, my embarassing error . . . I now inspect a lot closer to make sure the old seal came off, before installing the new oil filter on my cars or bikes.    

Rob Spiegel
User Rank
Blogger
Re: The devil is in the details
Rob Spiegel   11/14/2011 10:55:15 AM
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Hi David,

Can i use this in a future Monkeys column?

If so, please send along you full name to: rob.spiegel@ubm.com

Thanks.

vectorhappy
User Rank
Iron
pcv valve rattle?
vectorhappy   11/14/2011 9:59:18 AM
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Did the new pcv valve rattle before installation? Most pcv valves use a stainless steel ball as to provide the one way flow - and the ball will rattle when the pcv valve is shaken (not stirred)....if it doesn't rattle, it is stuck.

Sometimes saving a few dimes doing your own oil-changes / repairs can be costly if you don't know what to check along the way, including how to lube and check the seal on an oil-filter prior to installation.....

One example of this was a friend that decided to wire up the lights / brakes on his new horse-trailer. Everything seemed fine until the trip home after dark and turning on his lights caused his trailer brakes to engage. We all had a good laugh when he told us the story. The friend was a qualified EE with multiple patents to his name, but didn't know what he was doing when wiring the new trailer lights.

vectorhappy (one with dirty fingernails and scarred knuckles)...

jmiller
User Rank
Platinum
Re: pcv valve rattle?
jmiller   11/14/2011 10:44:13 PM
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I'd laugh, except I've done the same thing.  Wiring them darn trailers isn't easy.  Even though I'm an ME I sure thought I could follow a simple schematic and put everything together in the right way.  Little did I know.

William K.
User Rank
Platinum
Backwards? PCV valve??
William K.   11/14/2011 10:52:17 AM
The problem with the crankcase becoming pressurized from a stuck valve is due to the valve being in the wrong location. The PCV valve is not supposed to vent to a pressurized manifold, since that would not vent at all. What was wrong is that the valve was not routed to vent into the intake path before the turbocharger, in the area that is not pressurized. That is one of those things that sometimes gets overlooked when modifying an engine.

And I really wonder about how long it took to reach hydrostatic lock and break three pistons. That does not seem like an instant sort of occurrance. 

As fpr Fram oil filters bursting, I can't imagine that happening, of course, I only put them on American cars. I have seen filters rust through, but that was a whole different situation.

bob from maine
User Rank
Platinum
Oil Filters
bob from maine   11/14/2011 12:58:24 PM
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Quickie oil change places are notorious for 'double gasketing' and using cheap oil filters. If you have one of these places change your oil, ask for the old filter in a plastic bag; check to make sure the the o-ring gasket is with it, if not, find out why. There is generally a reason why most manufacturers offer different grades of oil filters for different prices, the difference in cost is insignificant over the life of the car, buy the best you can find. Regarding the PCV valve, it is likely the original had come with the turbocharger kit and did nothing but block off the vacuum line, or was deliberately installed backward to prevent damage.

Lauren Muskett
User Rank
Platinum
Re: Oil Filters
Lauren Muskett   11/15/2011 2:20:01 PM
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Asking for your used oil filter is a great tip, especially at the quickie oil change places. I am always concerned with what goes on with my car when I bring them to those places. You definitely get better quality oil/filter when you do it yourself, but soemtimes it just doesn't happen that way!

Critic
User Rank
Platinum
PCV Misunderstandings
Critic   11/14/2011 4:12:04 PM
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A PCV valve should not be relied upon to prevent boost pressure from pressurizing the crankcase.  Also, it is important to understand that the crankcase will be pressurized while the engine is boosted, from blow-by.  When a turbocharger or supercharger is added to a car, it is very important to re-engineer the PCV and crankcase venting systems.  I suspect that in this instance, this was not done.

Charles Murray
User Rank
Blogger
Website
Charles Murray   11/15/2011 4:07:38 PM
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What a great website link. Simple products -- such as PCV valves, oil filters, and fuel pumps -- have the potential to turn small problems into a fatal ones, as was almost the case for this writer. Thanks for the website link. We should all take a hard look at it, especially those of us who are do-it-yourselfers.

wade
User Rank
Bronze
turbo pcv setup
wade   11/17/2011 10:16:16 AM
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william has it correct.  pcv should connect ahead of turbo.  also, broken pistons from hydraulic lock or combustion pressure?  turbo would never drain into the intake manifold.  blow the turbo oil seals and you will get smoke but will get oil to the cylinders if you are cranking without the engine firing.

shjacks45
User Rank
Bronze
Something wrong with turbo
shjacks45   11/21/2011 4:02:17 AM
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1. Aircraft turbocharger for 280 HP aircraft engines placed on a 140 HP auto engine? This series of parts could be turbo-normalizers, which upgraded 18,000 ft altitude air (3psi, -20 degrees) to sea level air pressure. As a turbocharger, several engine changes such as lowering compression ratio is required (late 70's 280Z had 10:1 compression ration; the aircraft engines were 8.5:1 needed lowering to 7.5:1). On the aircraft engines the turbos were originally used on, 70F air was compressed to 198F (results in power loss when used without intercooler) .

2. Exhaust turbo engages at low engine RPM?

3. Stock 1979 Nissan 280ZX has a carbuerated engine. Carburator are designed for a manifold vacuum. Positive Crankcase Venilation valve is designed to take oil fumes (gas, etc.) from the crankcase headspace and using the Manifold vacuum to pull them into the engine and burn them.

4. PVC valves were added to reduce air pollution. Older cars did not have them and newer vehicles operate satifactorily when they are clogged.  The question implied is why did you feel that you needed to change the PCV valve, presumably there were engine problems such as excessive oil usage?

5. FRAM would not be liable for any damage caused by using its replacement parts outside the parameters that the original part was designed for q.v. engine with non-Nissan turbocharger.

6. You say you under rated your 14 psi turbo to 9 psi. Measured or settings for the original spec 280 HP aircraft engines (which take in twice as much air as the 280Z)?

7. Gee, if I saw oil "jetting" into my turbo I do not think I'd continue running the engine. Your dialog seems to indicate you revved the engine until it blew. Manifold detonation would be a likely cause of your engine damage. Engine oil ignites at a much lower temperature than gasoline, the extra 200+ degrees from compression, high compression engine, boom.

 

 

 

Keldawwg
User Rank
Gold
Re: Something wrong with turbo
Keldawwg   11/21/2011 2:18:40 PM
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A couple things...

It was not an aircraft turbocharger, it was simply an aftermarket turbocharger that was fitted to a car that did not originally have a turbocharger.  It was added to the car to increase the performance of the engine...

Exhaust turbo engages at low engine rpm? I don't know what you are asking with this question... The car had a small amount of turbo lag where the engine responded more slowly than a non-turbocharged engine until the exhaust flow was sufficient to spin up the turbocharger and start providing boost pressure. So from 600 RPM (Idle) to about 1500 RPM the engine did not have any increased power, in fact it had less power than a stock 280ZX. From 1500 RPM on, the engine produced a great deal more power than a stock normally aspirated engine. The time elapsed from 1500 rpm (Starts to develop boost) to 3500 rpm (approximately when the engine blew up) was perhaps 2 seconds...

The waste gate is a device that opens to vent any additional pressure beyond what it is set at. At 9 pounds of boost, the car performed great and did not require any additional hardware to keep detonation from happening. The engine did not knock from preignition at that boost level. The straight six in the Z cars was developed from a design originally licensed from Mercedes-Benz, 7 main bearings, 8.3:1 compression ratio and one of the most durable engines ever produced by anyone...

PCV valves were added to cars when they could no longer just vent the crankcase. (This is what they had on cars manufactured before the late 60's... Just simply a vent...) They wanted to pull the blowby gases from the crankcase. Without a PCV valve, if there was a backfire in the intake manifold, it would have a direct path into the crankcase, which would likely ignite the air-fuel mixture which is present in all internal combustion engines. I think you can imagine why this would be a bad thing. At the very least, the engine would probably blow a few seals from the internal pressure...

PCV valves need to be replaced regularly for two reasons. If it is clogged, and no air is being drawn from the crankcase, the resulting pressure from the blowby gases could blow your seals on the engine because the engine is now a sealed unit... If it is stuck open, the backfire-blown engine scenario could happen just like when they didn't have the PCV valve in place... A PCV valve is simply a calibrated air leak from the crankcase to the intake manifold... But probably it's most important function is that it is a one-way valve. Air is supposed to flow only one direction. From the crankcase to the intake. This is why I stated that the PCV valve was defective... If it was installed in a non turbo charged car, the result could have been blown engine seals; in a turbocharged car the problem was a bit more dramatic...

Question 6... Is there a question there? I didn't under rate my turbo, I just simply adjusted the waste gate so that it would open at 9 pounds of boost. This means that the turbocharger would never pressurize the intake system with more than 9 pounds of pressure.

Question 7... Ummm, in the 2 seconds going from 1500RPM to 3500RPM, I was driving my car... Specifically, I was in second gear accelerating to approximately 45 miles per hour. I didn't see the oil jetting into my turbo, I saw all this evidence as I was taking the car apart to replace the engine. I had no advance warning; one second the car was running perfectly (with 260,000 miles on the clock) and the next it was dead.

A 1979 280ZX did not have carburetors... 1974 260Z was the last year the Z cars had carburetors in the US... I believe that some Fairlady right hand drive cars produced for the Asian markets might have had carburetors as late as 1975, but by 1976 world wide they all had common rail fuel injection...

I did not try to get Fram to pay for my engine... I just chalked it up to a learning experience; never buy ANY Fram products. Fram oil filters are the absolute worst you can buy, I have seen several cars destroyed by them, and a couple motorcycles as well. I worked as a mechanic all the way through school becoming a mechanical engineer; I have seen a lot of shoddy products produced by companies that used to make good stuff. Fram tops the list easily. I once replaced an engine for free for a single Mom with three kids whose engine was destroyed when her Fram oil filter split wide open on the freeway and her engine seized. She had no warning either; one second she was driving to work, the next her engine was locked up so hard she spun out of control on the freeway... I took pictures of the oil filter, and Fram graciously offered to refund her the purchase price of the filter... It was all she could do to pay for a used Japanese engine, which back then was around $350...

Rob Spiegel
User Rank
Blogger
Re: Something wrong with turbo
Rob Spiegel   12/23/2011 2:49:08 PM
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Hey Keldawwg, that's the kind of detailed comment that realkly raises the bar on comments. Thanks for all the detail.

shjacks45
User Rank
Bronze
Thanks for confirming my comments
shjacks45   11/21/2011 8:43:40 PM
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@Keldawwg:

 Thanks for verifying my comments (& @wade's).

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