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Discussion Starter #1 (Edited)
Well I have finally found a way to stop the oil from going through my engine. For those who aren't up on my dilemma--back over a year ago my ccv gave up the ghost and the car sucked up some oil while out on the road--I heard all sorts of stuff go on before I could shut her down--

I have replaced the CCV and all hoses now three times to no avail-- the car has used 1 quart of oil every 1000 miles and sometimes more---I tried to run the car with out the cranck case from being evacuated--did this with a tube going to the valve cover and running out the bottom and letting the gases be pulled out like the old days--via a road draft tube--didn't work still used the same amount of oil--tried to use a oil catch can--still used oil---

I started to read around on different Forums and found one idea that caught my eye--Mustang forum talked about a way to remidy the problem by adding more vacuum to the crank case--they used a scavenger system--don't have one of those though:roundel:

I now have hooked the distribution unit direct to the valve cover and bypassed the ccv and instead of around 5 or 6 inches of vac goinging into the crackcase--there is now around 18 inches---this has ceased my oil useage---I have driven the car for around 2000 miles and the oil is right at the top of the dipstick like the old days. This is due to the vacuum being added to the crankcase--this helps seal the rings from down under and has stoped the oil useage.

I'm thinking that if I drive the car like this for another 30 days--this may seal my rings
back up enough that the ccv valve can be hooked back up again---

Anyone have any input on this idea?
 

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Anyone have any input on this idea?
I don't know. You are a genius? :dunno:

mw
 

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Discussion Starter #3
I'm far from that---just trying to get an idea if I'm thinking right---if this approach will work--or if it's not viable.
I guess a vacuum pump could be hooked up someway to do the job--that would call for someknid of bracket to be configured and a longer belt for driving it--this type of system would have an added benifit of some extra hp gains---but it would be expensive to configure.
 

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How much vacuum is in the crankcase when the system is properly configured? If just a very small amount (3-6 water inches), it may be that the oil separator is clogged, and is allowing oil to be sucked into the intake, and then burned.

If so, it will eventually ruin the cats.
 

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Discussion Starter #5
Normal vac is around 3 to 6 as indicated--but here is the rub--I have changed out the seperator 3 times with new units and each time the same problem---before the origanal ccv went south--never used any oil between changes--afterwards--1 qt every 1000 miles. So there is no way the ccv is cloged---I have also checked the system with vacuum test to make sure everything is sealed properly also
 

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I do not see how higher vacuum could possibly help with sealing the rings in any way. If for example, you have badly leaking valve seals, high vacuum might be able to greatly reduce the oil leaking past the seals though the valve guides into either the intake or the exhaust.
 

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Discussion Starter #7
I would have thought the very same thing until I started checking around as indicated above---vacuum brought into the crankcase can and will enhance piston ring seal---I'm not smart enough to know why
but there are oil scavaging systems out on the market that do that very thing for hot rods, using
vac pumps. These cars equiped with add on vac pumps hooked into the cranck case will develop more hp
and thats done by evaquating the crankcase of blow by---get the blowby out of the system--the system seals better--this can be proven on a dyno also. Check the following site for a little more info--now of corse I'm not adding a ton of vacuum like in the attached info--just what the engine now produces--but what I have inttroduced solved my problem.
http://www.highperformancepontiac.com/tech/hppp_0703_pontiac_evac_pump_kit/index.html
 

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While it's nice to seem to have fixed the oil usage issue, I feel that its only temporarily hiding the real problem. Start with a compression test and a leak down test and go from there.
 

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Discussion Starter #9
Did a comp test just a few weeks back--all cylinders read right at 180 lbs---car now has 160k miles --runs great and pulls just fine---only thing that I'm trying to rectify is this oil useage that came out of no where--as for a leak down test--I don't have the tools for that one--but I'm going to keep this project going for another few weeks and then go back to my ccv valve and see whats happening--As stated above--Driven the car over 2000 miles like this and no ill affects--just that the oil useage has stoped---got to add when driving at high speed the usage was bad--now driving at high speed no oil is being used--has me hopeful that I can at last get a handle on this problem with out swapping out with a new engine---thats what I had in mind if this didn't work.
 

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I now have hooked the distribution unit direct to the valve cover and bypassed the ccv and instead of around 5 or 6 inches of vac goinging into the crackcase--there is now around 18 inches---this has ceased my oil useage-
Question:
When you say "inches of vac" are you talking water or mercury?

It is my understanding the CCV (measured at the valve cover) is around 3-6 inches of water, and the intake is 18-22 inches of mercury at idle. 18 inches of mercury = 240 inches of water.
 

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Discussion Starter #11
Hell if I know which it is--I'm pulling around a 19 on my vac gauge--what ever that is measured by is what
is going on inside the crank case---If this doesn't remedy the problem, there will be an engine swap--Don't want to go through that if it can be helped. Have read of many that have had this same problem come along and bite them--hoping this will work so that others can benifit----will be posting back with the results of course.
 

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I'm pulling around a 19 on my vac gauge--what ever that is measured by is what is going on inside the crank case---
More than likely, we are talking "inches of mercury." (most vacuum gauges measure vacuum in this unit)

You have increased the negative pressure in the crankcase 40x more than stock. I don't think this will be a problem. It should reduce pumping losses and may increase your HP just a little. Many race engines do this.

Please keep us updated on this!
 

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Discussion Starter #14 (Edited)
Hey CN90---I haven't a camera to make the pics happen--but what I have done is--used a peice of 5/8 outside diameter rubber vac hose and attached it to the large opening on the distribution unit----the small opening on the distribution unit is sealed with a vacuum cap. The other end of the 5/8th vac hose is inserted into the side of the valve cover that would be used to hook up the ccv valve--so all and all the vac is going straight from the intake to the crankcase without any ccv valve---works great so far---
On the dipstick tube--yes I cleaned it up to speck--even bought a new one to be sure--nothing helped the problem --except with what I have come up with in the above.

Max--on the vacuum increase--on hte link I provided above is info on adding vac pumps to older V* engine's and after dynoing--they were coming away with as much as 30 horse power---so I figure with the right pump added you might come away with 5 hp in one of the I6 cars.
 

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I wouldn't hook the CCV back up again, ever. Regularly check your oil cap gasket and your dipstick o-ring to make sure they don't become huge vacuum leaks and keep going with this.

You may want to add a check-ball type conventional PCV valve and a catch can to the system to prevent you from pressurizing the crankcase under WOT and condense more of the oil out of the crankcase gases to keep them from being burned and possibly fouling a catalytic converter.

I'm considering bypassing the oil separator on my 540 with a catch can and PCV valve. Our oil separator is buried behind the timing chain and difficult to replace or clean if it clogs.
 

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Discussion Starter #16
Have thought of doing that very thing Ascott----I would indeed just drive on except for one thing--with this hooked up this way I have codes from both banks 1 and 2 that says the car is running rich---also the cars a little harder to start in the morning when cold---I have checked the crank case through the vent hole in the valve cover for a vacuum leak yesterday---all is sealed and the crank case holds vacuum---so to get the car back into open loop --gotta get the emmisions hooked back the way the car came from the factory---if this doesn't work though--I will drive the car just like it is--I'm still getting good gas mileage and the car doesn't burn one drop of oil the way it is right now---the service engine light is on and I can live with that if I gotta.
Guess time will tell how all this turns out---going to add---before hooking this up like this the exhaust pipe would be wet and gummy with black looking oily exhaust residue--now the pipe is burning so clean you can drag your finger through it and not see a hint of carbon.
 

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If it has good compression (180psi on all cylinders) then you need to perform a leak down test as the next step. This will show you more about the condition of your rings.

I think you've got the vacuum pump idea slightly wrong- the main reason we put vacuum pumps on the older muscle cars and hotrods is not to gain power. Its because when we install performance camshafts, the camshaft has more overlap. This inherently reduces vacuum at idle by a large amount. So crankcase gas evacuation and power-assisted brakes dont work very well with such low vacuum. So we run the vacuum pumps as a substitute.

Car Craft magazine has a lot of good online articles on this (its a hotrod/muscle car magazine), that are worth reading if you can google them up :)
 

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I give you points on the ingenuity scale for sure ! I haven't delved into my CCV repair yet (just passed 180k on the motor) ... but I am sure it is coming.

Hope the results of my pending R&R are different but if I end up with a BMW burning oil like my air-oil-cooled p-cars ... this thread will help.

Sorry for your troubles.
 

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Have thought of doing that very thing Ascott----I would indeed just drive on except for one thing--with this hooked up this way I have codes from both banks 1 and 2 that says the car is running rich---also the cars a little harder to start in the morning when cold---I have checked the crank case through the vent hole in the valve cover for a vacuum leak yesterday---all is sealed and the crank case holds vacuum---so to get the car back into open loop --gotta get the emmisions hooked back the way the car came from the factory---if this doesn't work though--I will drive the car just like it is--I'm still getting good gas mileage and the car doesn't burn one drop of oil the way it is right now---the service engine light is on and I can live with that if I gotta.
Guess time will tell how all this turns out---going to add---before hooking this up like this the exhaust pipe would be wet and gummy with black looking oily exhaust residue--now the pipe is burning so clean you can drag your finger through it and not see a hint of carbon.
If you're coding rich, then you have a leak that's allowing air into the intake tract via the crankcase.

The engine is a closed system with one inlet - the MAF, and one outlet - the exhaust behind the last O2 sensor. That means your inlet for the crankcase ventilation system must be AFTER the MAF. If you're venting from somewhere else, or your oil cap leaks air, or some other spot, then you get extra air in the system, the computer will dump fuel to compensate, and you get an uncontrollably rich situation.
 

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If it has good compression (180psi on all cylinders) then you need to perform a leak down test as the next step. This will show you more about the condition of your rings.

I think you've got the vacuum pump idea slightly wrong- the main reason we put vacuum pumps on the older muscle cars and hotrods is not to gain power. Its because when we install performance camshafts, the camshaft has more overlap. This inherently reduces vacuum at idle by a large amount. So crankcase gas evacuation and power-assisted brakes dont work very well with such low vacuum. So we run the vacuum pumps as a substitute.

Car Craft magazine has a lot of good online articles on this (its a hotrod/muscle car magazine), that are worth reading if you can google them up :)
A Leakdown test does not tell you the state of the oil control rings. Only the compression rings.
 
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