Why I measure crankcase blow by gases and vacuum.... & so should you! Air leaks!

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Jack@European_Parts

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Why I measure crankcase blow by gases and vacuum.... & so should you! AIR LEAKS!

Cause verse Effect! JPPSG rule......Final Solution Section!

http://forums.ross-tech.com/showthr...essional-Problem-Solver-Guide-quot-JPPSG-quot

Over the past 15 years, I have observed all the platforms & especially TFSI/TSI engines and the so called, need for a ridiculous oil specification or blow by gases remediation design process.

A large discussion of this took place in Marin's oil thread....... http://forums.ross-tech.com/showthread.php?2224-Oil

The reason I feel this is needed as part of the how to section.....


It appears that a critical diagnosis of air leaks is being negated, further where many result in a phantom untraceable air leak, long after intake manifold and N80 are all been changed.

You will find on occasions that Jef, Dana, and Peter speak of rear seals popping on the crank, further causing an air leak.

You may also find them saying you need to use propane to find it.......indeed this is helpful when measuring trims, but also has its safety issues.

What you don't find is why and how did this condition ever happen in the first place.

It happens 3 ways.

A. Flash block combustion explosion internally, from contaminated oil with gasoline from misfires and heavy vapor concentration or oil now a solvent as a result blowing seals.

B. Blow by gases too high & as a result of washed cylinder walls failed piston rings and or damaged components such as HPP.

C. Direct Boost leak by oil separation check valve stuck sometimes sporadic & from sludge allowing for boost to be directed into the crankcase.


C. Happens all too frequently and more than people realize internally within the engine.........it hides like a sniper in the brush.

When boost is made while this valve sticks open, the seal expands and further while not leaking oil yet!

The engine comes off boost and we are at idle or idle offset at a traffic light waiting on a hill and bam the air under vacuum leaks in and into the intake causing a deviation setting a DTC.

Further the oil pooled in the check valve now creates a seal and the valve closes drawing the seals in, in addition some oil into combustion process causing a misfire at idle....or offset!

Wonderful right?

How to observe....


Installing a PSI/Vacuum gage to block area or one which can be logged.

Originally the experiment started out to prove that "any" ( for Eric ) SAE oil sealed piston/rings + lubricated chains, far better or critical friction components, such as the HPP or cam lobe/follower, than the required VAG specification using synthetic oil.

Ahhh oh pump the brakes right? Wait What! are you kidding we were taught otherwise?
Basic's will tell you I am right in addition to statistics.

The results were almost immediate....... :thumbs:

Any SAE oil was used in short 3-5K intervals, the engines ran far superior for internal longevity.....and I stand behind this position to date.
May the HPP/cam followers & chain failures speak for themselves.......... :rolleyes:

A set of gages were added to the block, with a reset to record the highest or lowest level observed.
Later electronic gages were used which could be used in real time & or logged.

Note : The dancing or sucking down loose oil cap test ........"is ok" but doesn't cut the mustard or address the hidden flaw I aforementioned.
The point is measuring the Vacuum/PSI through an oil cap being drilled, further while watching a gage during a test drive, can be a great diagnostic indicator.

Any schmuck can make this tool in 30 seconds, with a stretch of vacuum line, an old oil cap and a cheap vacuum gage PSI set.........you do this to be able to wire tie to the wiper etc. & to go observe through the window during logs or just before DTC. pends.













 
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Eric

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1) Worthless without pics/video ;)

2)
Originally the experiment started out to prove that SAE oil sealed piston/rings + lubricated chains far better or critical friction components such as the HPP or cam lobe/follower, than the required VAG specification using synthetic oil.
What Jack means by SAE, is conventional, non-synthetic oil. Even Jack wouldn't put non-SAE J300 rated oil in an engine :)
 
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Jack@European_Parts

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I sent pictures to Eric to post because he will want them posted as clean as possible.

Simple stuff to make....... takes 30 seconds.

Right hand barb with self sealing taper insert to drilled hole on center of the oil cap.

Quick..........

https://postimg.org/image/4kp2mvfbb/




I would extremely appreciate feedback on the helpfulness of use of this method as a diagnostic path when successful by all users!

Thank you!

NostraJackAss Has Spoken & Made a Requested for a Response to the Collective!
 
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Jack@European_Parts

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What Jack means by SAE, is conventional, non-synthetic oil. Even Jack wouldn't put non-SAE J300 rated oil in an engine :)
Well............Huh what?

http://standards.sae.org/j300_201304/

[h=1]Engine Oil Viscosity Classification[/h]
Standard:



Revised:


  • 2013-04-02









Issuing:







Publisher:


  • SAE International





Pages:

9



Scope:

This SAE Standard defines the limits for a classification of engine lubricating oils in rheological terms only. Other oil characteristics are not considered or included.




Rationale:


This revision begins the process of extending the SAE Engine Oil Viscosity Classification system to lower high-temperature high-shear-rate (HTHS) viscosities by adding a new high-temperature viscosity grade – SAE 16 (>2.3 mPa s HTHS) – to SAE J300. In addition, the minimum 100 °C kinematic viscosity (KV100) of the SAE 20 grade is raised from 5.6 mm[SUP]2[/SUP]/s to 6.9 mm[SUP]2[/SUP]/s. A formal request for this new grade was presented to the Engine Oil Viscosity Classification Task Force (EOVC) by the International Lubricant Standardization Advisory Committee (ILSAC) on September 21, 2011 as well as on earlier occasions by a number of individual original equipment manufacturers and oil companies. The benefit of establishing a new viscosity grade is to provide a framework for formulating lower HTHS viscosity engine oils in support of the ongoing quest of engine builders to improve fuel economy.
The minimum KV100 of the SAE 20 grade is increased from 5.6 mm2/s to 6.9 mm[SUP]2[/SUP]/s for two reasons: (1) equipment manufacturers desire to narrow this range to ensure proper operation of hydraulically-actuated engine control devices which are sensitive to kinematic viscosity and (2) the lower portion of the KV100 range is not being utilized and is outside of the formulating range of oils with HTHS viscosity > 2.6 mPa s. The new minimum value of 6.9 mm2/s was selected to provide the same KV100 range as a fraction of the minimum KV100 of the SAE 20 grade {(9.3-6.9)/6.9 = 0.35} as the current SAE 30 grade {(12.5-9.3)/9.3 = 0.34}. Raising the minimum KV100 is not expected to impact commercial SAE XW-20 lubricants in the marketplace.
The KV100 range of the SAE 16 grade overlaps that of the SAE 20 grade. This represents an historical departure from non-overlapping KV100 ranges in SAE J300. Allowing overlapping of these two grades was done to provide adequate formulating space for the new grade. Assignment of a single high-temperature viscosity grade to an engine oil with KV100 in the overlap region (6.9 – 8.2 mm[SUP]2[/SUP]/s) is covered in Section 6 of this document.
 
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Eric

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16 is old news. They're up to (well down, really) 12 and 8 now.
 
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ivagp

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what about hooking up at the dipstick?
 
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Jack@European_Parts

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what about hooking up at the dipstick?

Later cars don't all have dipsticks...........and some dipstick tubes extend into the oil itself, but sure why not for cars that have it and don't extend into the oil.

This was just a means that anyone can get access to and the fact it's cheap & easy to do getting access to PSI values at the top of the engine as heat rises.
 
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Geoffzie

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OK Jack, so if I did this ... what numbers should I see? From your own experience? What would be considered "normal" readings ... and what would be considered "abnormal" readings? Would they be similar to "normal" vacuum readings?
 
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Jef

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Jack,

Is there a specific gauge you suggest? Brand/model? Some gauges may not registered the low values very well, or at all.
 
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Jack@European_Parts

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Jack,

Is there a specific gauge you suggest? Brand/model? Some gauges may not registered the low values very well, or at all.
I didn't even think of that because I am still using my snap-on sets from 30 years ago and which say "Made in USA" on them. :rolleyes:

In addition my all metal Mighty Vac sweeps in both directions on a single line plugged in too....

Let's see.......this would be cheap enough maybe....no?

Example not endorsed seller, nor am I selling this.


Eric found this one....

http://www.ebay.com/itm/GREAT-Fuel-...e=STRK:MEBIDX:IT&_trksid=p2057872.m2749.l2649

http://www.ebay.com/itm/2-Utility-V...495478?hash=item1c3680ceb6:g:bDgAAOSwVcFXPISk
 
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Jack@European_Parts

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O
K Jack, so if I did this ... what numbers should I see? From your own experience? What would be considered "normal" readings ... and what would be considered "abnormal" readings? Would they be similar to "normal" vacuum readings?
I am not going to disseminate the base figures at this time.

See that is going to have to be determined by trial on your own, as can others report back numbers found & to compare and build a database for each platform they are testing.

Engines and wear + situations differ but it is the drastic change you are seeking & that points to a problem while on a real life road test.

Now it's your & everyone else's turn to engage the collective to contribute.


 
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Jack@European_Parts

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Let me say this to be clear.......this method of diagnosis is for anomaly's in the crankcase gasses for vacuum or boost/PSI & which can also be excessive, due to blow by.

A base reading of what normal vacuum or PSI can be seen in the intake manifold & to compare them, you should not be so concerned with what is a normal value by just observing the base PSI or vacuum in the crankcase as a rule.

Crimp tests can be used to isolate and establish a base line for any specific motor, further by cross checking values or isolating check valves.

As for what Jef aforementioned about values not being able to be seen depending on a gauge.
I kind of strongly disagree here.
You can see for yourself by inducing issues such as a stuck PCV valve or Boost being permitted to divert directly into the crankcase. This will register pretty drastic on a road test & when either conditions are present being out of bounds.

If excessive vacuum is found in the crankcase the engine will consume oil and plug stuff up and when in a boost leak or high blow by situation carbon build up at valves will be excessive and seals will weep or stretch; to the point they leak air causing a trim to go dump fuel. This results in issues such as SAI tubes plugged etc........hence more oil consumption issues.

Both issues if not kept in a working zone of equilibrium, will cause an oil consumption issue or induced oil leaks.

Please think of basics of operation and where do gases come from, how do they effect a situation vicariously & when they are triggering a phantom MIL.
 
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OKrepairer

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thats a great idea and where might i buy a gauge just like yours?
 
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Jack@European_Parts

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WHAT NO STICKY .............?

This thread is very important that people start observing it! :rolleyes:
 
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