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Oil separator question....

mistapickles

By mistapickles,
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mistapickles Newbie

mistapickles

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I have a complete hard pipe setup in my car but really understand the importance of an oil separator. So yesterday I welded a bung on my ahp to allow the upper hose on the oil separator to connect. The car feels much better. Anywho, as I was driving in to work this morning doing my typical gymkhana session in traffic I got to wondering about my oil separator. It was designed for 8 psi and I'm easily running 15 psi and plan on running 18-20 psi after I get my upgrades done. Is this increased pull in the ahp creating greater pull in my engine? Is there a plus and/or minus side to the increase in vacuum? And if the negative outweighs the positives is there a valve I can use to control the amount of vacuum pulling on my oil separator?
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Shelby
Shelby

come on guys ,,you can tune a fuel system and install a huge turbo but wireing a dip stick in place you never think of ???how   long is that rubber oring expected to last ,,that's all that holds th

Caliber308
Caliber308

After all the replies in this post, it comes down to this: Whatever the set up your running.....What works as far as modifications to/and or elimination of the Oil Seperator, it seems that most of us

Funky Phil
Funky Phil

booyah!

Frenchi934 Newbie

Frenchi934

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id really like to see someone who knows chime in here because I also have the factory oil separator on my setup and im running 30psi. under heavy boost i notice that my car smokes and im nearly 100% positive that its because the catch can cant separate with that much vacuum being pulled on the top hose.

 

Ive noticed some of the big HP setups run a separators that dont have a vacuum source, just vents on the top.

 

anyone have any input?

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aknorthstar Explorer

aknorthstar

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After installing my new Garrett turbo I noticed my car started smoking after hard boost. Running 15 psi. I removed my oil separator and installed a breather on the valve cover. I noticed a lot of high hp cars on this site that run a simple breather on the valve cover and tried it. It took care of my smoke problem instantly. Car runs great!
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mistapickles Newbie

mistapickles

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After installing my new Garrett turbo I noticed my car started smoking after hard boost. Running 15 psi. I removed my oil separator and installed a breather on the valve cover. I noticed a lot of high hp cars on this site that run a simple breather on the valve cover and tried it. It took care of my smoke problem instantly. Car runs great!

the oil separator causes vacuum in the crank case and the head so the problem with just having a breather on the valve cover is the oil pump runs four quarts of oil in two seconds at 4k rpms and with that it empties your oil pan in TWO seconds. If you don't have vacuum in the case helping pull that oil down you can actually run your engine without oil at a high rpm in a turn not to mention you're absolutely making oil bubbles/foam because the pickup is pulling air and oil because the oil isn't coming out of the head fast enough AND it'll float in a mist in the case because of all the spinning parts. The vacuum the oil separator creates is absolutely necessary and can be gotten around.
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Caliber308 Collaborator

Caliber308

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I eliminated my Stock Oil Separator in 2005 without any negative effects. I small breather off of my rear valve cover and installation of the K.V. system have served my set up well.

 

Bill

Edited by Caliber308
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ucw458 Grand Master

ucw458

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the oil separator causes vacuum in the crank case and the head so the problem with just having a breather on the valve cover is the oil pump runs four quarts of oil in two seconds at 4k rpms and with that it empties your oil pan in TWO seconds. If you don't have vacuum in the case helping pull that oil down you can actually run your engine without oil at a high rpm in a turn not to mention you're absolutely making oil bubbles/foam because the pickup is pulling air and oil because the oil isn't coming out of the head fast enough AND it'll float in a mist in the case because of all the spinning parts. The vacuum the oil separator creates is absolutely necessary and can be gotten around.

 

 

It doesn't work that way.

 

The separator is pulling from the VC and most of the crankcase pressure is coming from the rings. So if anything those gasses flowing to the separator would prevent oil drainback to the pan. But they aren't powerful enough do to anything like that.

 

 

The real benefit of a separator is pulling a vacuum on the crankcase helps the piston rings seal better.

 

 

 

 

I've been thinking about using something like this,

 

http://autoplicity.com/products/495947-moroso_23534_vacuum_pump_pulley.aspx?utm_source=google&utm_medium=cpc&utm_content=495947NOFITMENT&utm_campaign=GSNOFITMENT&adtype=pla&kw=&utm_term=&adpos=1o2&network=g&gclid=CLGYxaeIh7cCFadxQgod8nIAKQ

 

Maybe mounting it where the AC idler goes and run it off that belt. And add an aftermarket oil separator.

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scott87star Contributor

scott87star

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I've measured the vacuum generated at stock boost levels by the oil separator, its a psi or two at most but the absolute value isn't as important as it represents flow or flow capacity. I would expect as long as you're able to pull vacuum at any boost pressure/rpm combination you're enjoying the design benefits of the separator. More vacuum is not bad given lower rpm cruise can apply 20 inches of mercury to the crankcase through the PCV (about 10 psi vacuum). It's when you no longer can get into the vacuum at that port where you run into problems.
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mistapickles Newbie

mistapickles

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yeah, that's part of the problem, you don't want suction in the head because that means it's holding oil in your head. You want something that's going to let the oil out of the head and back into the oil pan, you want suction in the crank case.
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StarquestRescue Newbie

StarquestRescue

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id really like to see someone who knows chime in here because I also have the factory oil separator on my setup and im running 30psi. under heavy boost i notice that my car smokes and im nearly 100% positive that its because the catch can cant separate with that much vacuum being pulled on the top hose.

 

Ive noticed some of the big HP setups run a separators that dont have a vacuum source, just vents on the top.

 

anyone have any input?

Vacuum in the crank case is a good thing. I doubt i hose from the intake pipe can maintain vacuum under much boost. Vacuum in your intake is an indication your filter is dirty, to small and or the air flow meter is restrictive. Really i think the hose draws a draft from the air flowing over the opening vs actually having vacuum in the intake.

 

When the blow by from the rings over come the amount of draft, there is then positive pressure in the crank case and oil and smoke (blow by) tends to be more noticeable. If the oil that goes out the valve cover is not completely separated from the air it is sucked back into the engine and burned which also produces oil smoke.

 

This oil being drawn into the intake lowers the octane of the fuel, oil is also a fuel, and detonation can occure.

 

Real race cars use vacuum $ pumps and seldom return the oil to the crank case. On a street car it is possible to empty the crank case if the oil that is blown or sucked out is not seperated from the air and returned. Such a car engine would likly already be quite sick to have pushed out that much oil in the first place.

 

Most times, cars that have excessive blow by have ring problems or ring land problems.

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psu_Crash Grand Master

psu_Crash

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It doesn't work that way.

 

The separator is pulling from the VC and most of the crankcase pressure is coming from the rings. So if anything those gasses flowing to the separator would prevent oil drainback to the pan. But they aren't powerful enough do to anything like that.

 

 

The real benefit of a separator is pulling a vacuum on the crankcase helps the piston rings seal better.

 

 

 

 

I've been thinking about using something like this,

 

http://autoplicity.c...CFadxQgod8nIAKQ

 

Maybe mounting it where the AC idler goes and run it off that belt. And add an aftermarket oil separator.

 

I have thought of fabbing up something like that a lot but never found a suitable pump for anywhere near that price. Now you have me thinking ...

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MikeMeyerhoff Newbie

MikeMeyerhoff

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Really i think the hose draws a draft from the air flowing over the opening vs actually having vacuum in the intake.

 

I hadn't thought about it that way, but a venturi effect using a restriction would help. Sort of like the stock secondary air port where it enters the downpipe... that little shield is a venturi.

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Shelby Newbie

Shelby

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with 30 lbs boost there is only one place on the engine with any sort of vacuum , and that's at the air intake , it won't be a lot but the main point is to alow the engine blow by to reenter the engine and not blow the oil out in the engine compartment , and a clean flow of air from valve cover back into the air intake is what is needed , the separator has baffles to stop pure oil from being sucked into the engine

you said your running a garret turbo have you got an oil pressure reducer in line to the turbo oil port,, it's possible your blowing oil past the shaft seals and not from the crank case,

 

if it is blow by sounds like you are having an excessive blow by problem and that points to rings or ring lands causeing a stuck ring or rings

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Funky Phil Newbie

Funky Phil

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THE STOCK SEPERATOR SYSTEM HAS NO PLACE IN A PERFORMANCE BUILD.

 

Recycling into the turbo inlet is emissions tom foolery.

 

30psi tells me your trying to make power. crank case pressure works against all of your seals, oil return, and rings.

Without proper venting you will see

1. blown out dipsticks, VC, mainshaft, oil pan seal leaks

2. broken turbos due to lack of chra scavenging leading to overfilling/overheating/overpressurizing

3. broken internals from contaminated air causing det, and ring/land failure.

 

You can try a venting system, ensure the lines are large -10 or multiple -8 with large vents. good for a street car but will leave the cabin smelling like oil after a couple pulls and filters will require regular cleaning. Make sure your catch can is baffled and DO NOT return it to the pan.

 

vac pump, GREAT for performance cars but quality pumps come at a price

 

Exhaust EVAC. cheap but can be tricky to get it working right. Not emissions friendly but also doesnt leaving cabin stinking.

Dmyers posted a link to my setup. And it works great/too well at times.

Edited by Funky Phil
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Shelby Newbie

Shelby

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Exhaust EVAC. cheap but can be tricky to get it working right. Not emissions friendly but also doesnt leaving cabin stinking.

Dmyers posted a link to my setup. And it works great/too well at times.

 

Edited by Funky Phil, Today, 03:34 PM.

 

 

 

care to tell us where and when and what it lacks,, and phil do you drive your car as a daily

not trying to start a war just asking

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Funky Phil Newbie

Funky Phil

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Do you mean the stock system?

routing oil back into the intake is bad as was already stated by john (sqr) I actually was tuning a mpi hx35 car a month back that was pinging bad at 15-20psi. I looked at his setup and he was using the stock "routing" but missing the can. Now its wrong in sooo many ways to route it like he did, but it proves the effects of putting oil back into the airstream. I had him relocate the line to atmosphere venting and clean his IC and plumbing.

We were able to make 25psi 3-4-5 gear pulls with no ping. You could smell the atmosphere venting in the car though. Everyone I know running the "stock" system in "higher" HP applications is blowing the dipstick and spraying down thier bay.

 

Exhaust Evac, just needs a good baffled catchcan with a good flow capability. And a free flowing exhaust.

 

On my own car a few years back when I utilized a stock setup, it always misted inside my piping even with the seperator. It also would puff after pulls.

 

Is my car a daily? depends what you consider a daily. Do I drive it regularly? Yep. Every day? Not if its raining. Ask everyone that went to Little Rock, I drove it everyday to include the 2hr cruise to the dragstrip.

Edited by Funky Phil
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ucw458 Grand Master

ucw458

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Everyone I know running the "stock" system in "higher" HP applications is blowing the dipstick and spraying down thier bay.

 

That's probably why my engine bay has gotten a few oil baths from the dipstick tube. I get so pissed when that happens.

 

 

Good info here. When I get back to working on my car I'm gonna ditch the stock setup and run something better.

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Shelby Newbie

Shelby

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come on guys ,,you can tune a fuel system and install a huge turbo but wireing a dip stick in place you never think of ???how

 

long is that rubber oring expected to last ,,that's all that holds the dip stick in place

 

as for blowing oil, the entire time I drove my turbo truck ( over 5 yrs) I never added a qt of oil between changes, unless a hose leaked , @ 2k miles it'd be down aprox 1/4" on the stick , but I did run a total of slightly less then 8 qts of oil ,, never had the least bit of problem with blow by oil , even after I took the oil separator OFF the system

 

but every engine is a little diff ,,also a great many of these guys your talking to have marginal ring

sealing

 

all in all I care less how any one runs this or that but we have guys on here that have selective reading they only read what they want to , they hear the biger turbo and more boost but the warning about what happens with big boost they completely over look ,,UNTILL oh crap this POS blew up

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Caliber308 Collaborator

Caliber308

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THE STOCK SEPERATOR SYSTEM HAS NO PLACE IN A PERFORMANCE BUILD

 

You can try a venting system, ensure the lines are large -10 or multiple -8 with large vents.

 

vac pump, GREAT for performance cars but quality pumps come at a price

 

 

 

 

I have to agree with the above post.

 

A decent Belt-Driven Vacuum Pump set up for a 2.6....Appox: $500.00. A KrankVent system...... Maybe $120.00.

 

Stock 2.6 set ups produce between 19 to 22 psi vacuum.

 

With my KrankVent and Roller Camshaft: 17 psi Vacuum.

 

Bill

Edited by Caliber308
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