im gonna try it, anything to keep oil out of my new intake. im gonna route the pcv to the first can, then run the bottom line to the next can, then into the intake. just wondering if anyone else tryed it

 

I have a H/C motor and an AMC catch can---It fills up with about 1-2 ounces every couple of tankfuls---and--still the manifold is real oily--I installed a LS6 valley and PCV as well--no change---I'm totally lost as what to do also---It can't be good--I'm sure that synthetic oil isn't a good thing to promote combustion !!!! Took the manifolf off to clean it after 3000 miles---holy cow !!! what a mess---I can't believe it even runs at all with that much oil in there--intake ports oily too--and the heads are BRAND new.

 

Thats pretty scary! I just had a CC installed and was hoping not to have to empty it more than 2X/year (at regular oil changes). I may have to re-think that.

Pdd000: Our cars look like long lost brothers. Real sharp!

 

You guys might want to read this:

http://www.conceptualpolymer.com/PCV...oval%20101.pdf

I'm not surprised that a typical catch can does NOT trap all oil.

 

Wierd.... I have an Elite Enginering catch can... the line from teh valve cove to the TB is the fresh air feed line for the PCV system and isn't supposed to allow oil to move the other way. Some have said that at very high rpms a vaccum can be pulled there.

However, others have tested inline air compressor filters and PCV valves and they don't get oily... I have the one catch can... I empty it every few thousand miles and I'll stick w/ that.

 

Dave

Thats a great write up based on good research.....thank you

Couple of things:
1. " At full throttle, there is nearly zero vacuum. At this point the PCV valve is nearly useless, and most combustion gases escape via the "breather tube" where they are then drawn in to the engine's intake manifold anyway."

This quote from you reafirms why I see lots of oil in the breather line when at the track. And why I have been running some type of filter or can on this line as well as the PCV line.

2. I remain a little concerned that this type of filter will not restrict flow when exposed to maximum oil flow rates, like at the track. I think ideally (and what I would like to try) is to first have a can like the AMW or Elite in the oil path to trap the bulk of the oil and then let the smaller coalecsing finish the job.

3. Whats the chance that you could obtain this stuff at your reduced prices and make these available to forum members. You could mark it up and make some spare change

Anyways, I for one want to commend you for the time you have taken with this on going issue.


DH

 

Nice Dave!

 

Thanks, Howie and Lonestar. When you size a coalescing filter that is to be mounted downstream of a compressor (that contains oil), you should always make sure that the flow capacity of the filter exceeds that of the compressor. However, what you don't want to do is order a filter that has a flow capacity that is 20 times that of the compressor. The reason is that larger capacity filters are generally less dense to minimize pressure drop across the filter. Using the "mesh" I've seen in most catch cans is akin to having a 100 CFM filter in-line with air flow that peaks at about 1.5 CFM. The result is inevitably, a low percentage of trapped oil vapor.

The coalescing filter I chose has a flow capacity of 8 CFM - more than 4 times the flow that our PCV lines "see" (according to my measurements), yet its filter is far more dense than the filters used in the more expensive catch cans. Essentially, the Watts filter is the smallest one I could find.

I recently asked (in the C5 parts for sale section) if anyone would be interested in a group buy of the Watts filter/mounting bracket assemblies. I was going to order five of them, along with five of my extended filter bodies. There ended up being enough interest so that I ordered 10 sets of everything. An eleventh person chimed in a bit late.
I apologize for not telling you about it, but I honestly thought you had ordered one of the filters on your own. The total cost for each set of filter assembly and extended can, along with the brass fittings and thumb mounting screws is about $75 (+ shipping). I really believe that these filters will trap more oil than the average catch can, primarily because of the density of the filter material. I've been running my setup for 750 miles+ now and through a mountain run (short blasts of 120 and very high-rev hill climbing) and I have not noticed any drivability issues or lack of power. Then again, as you mentioned before, street driving is not nearly as harsh on the car as race track driving.

Hey, I can always order more filters; it's just that I (and everyone who orders one) save more as the quantity goes up. Then again, if you know anyone who runs a CNC lathe, give him my drawing and buy him a couple of six packs. I made my extended can (except the threaded part) on a manual lathe and it's no fun!

BTW, I mounted my filter where I feel is the best area for a coalescing filter (coolest spot that is somewhat easily-reached). Here's a pic.



Dave

 

2 cans is not the silliest idea in the world, but you'd want one on the PCV line and one on the fresh air / throttle body line. Running two in tandem is probably a waste.

 

thanks bro-yr car is smokin

 

why do you think that?

 

It's common knowledge that oil can and will enter the intake under certain conditions via the "fresh air" TB to valve cover line.

If you have a decent catch-can, anything that gets by it (airborne oil vapor) will probably get buy the second can as well.

If you buy two cans, it would only make sense to put one on the PCV line and one on the fresh air line. With that configuration you'll catch the vast majority of oil ingestion. A step further would be to buy two of those filter assemblies Dave has mentioned in this thread.

 

This is like having dropping two fishnets, 5 feet apart. Both fishnets have the same size openings and some of the fish you are trying to catch slip right through the course mesh of the nets. Whether you drop 2 or 10, those little fish will always slip through and since the first net caught the large fish, the second net will be empty or near-empty.

The trick is to use one finer-mesh net to catch everything (well, except for the plankton, which you are not interested in, anyway).

 

makes sense. so if i could get a finer mesh in the can that should do the trick? were do i get it?

 

Well, the easiest thing to do is what I did - buy a coalescing filter that was designed to trap oil aerosols under low-flow/low-pressure conditions. If you read the pdf article I wrote, you will see which one I chose.

Dave

 

thanks dave. i read the pdf-great read. to bad i missed the group purchase

 

Use one of my Oil Separators that is designed to extract oil from the air. Check my my website and click on the Oil Separator tab.

 

Dave

I can't believe you didn't include me in that group buy......I didn't know you put one together

Let me know if you do it again.....

DH

 

I never got to see the inside of Charlie's can (but I am going to!!!), however, I can state that it was very nicely constructed (almost looked like it was developed with CAD software )and much bigger than the Elite or AMW. Charlie also had it mounted up front like my AMW and Dave's.


DH

 

Howz about using one of those cheap, disposable vacuum brake booster filters? The ones that are (or at least were) OEM on many cars and light trucks for years. The have 3/8" hose fittings on each end and are about the size of a disposable fuel filter.
They were designed to keep oil/fuel vapors from backflowing from the intake manifold into the vacuum brake booster on carbureted cars/trucks. Don't know what filter media it uses, but they are inexpensive.
Robert