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ASA Oil Seperator -- bottom-line reviews

scrollF4

scrollF4

Moderator, Asst. Line Boy
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I have read a lot of great reviews in these fora supporting Anti-Splat's ASA Oil Separator, and I have a question for the group: Has anyone had difficulty with, or been disappointed by, the system, particularly regarding its performance?

I ask because I'm at the perfect point to order and install, and want to make sure I'm making the wisest choice.
 
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Did not help in my case

Hi Scroll,

I am also at 52F and installed the ASA air/oil separator on my RV-10. I was hoping the slight negative crankcase pressure would reduce some of the weeping and that the belly would stay cleaner. Unfortunately it did not help on the oil weeping and the belly still gets dirty. I saw no change in oil consumption or any noticeable power increase.

Just one data point....

TJ
 
RV-10 oil seperator

Thanks TJ.
It occurred to me that ASA's video discussed a larger oil separator for the RV-10 engine, but then their product list showed only one size separator. Do you have that standard ASA separator on your 200+ hp engine?
 
Bottom line is that for me it was simpler and faster to install than the bent aluminum tube supplied with Vans kit.
 
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Flying again! said:
Hi Scroll,

I am also at 52F and installed the ASA air/oil separator on my RV-10. I was hoping the slight negative crankcase pressure would reduce some of the weeping and that the belly would stay cleaner. Unfortunately it did not help on the oil weeping and the belly still gets dirty. I saw no change in oil consumption or any noticeable power increase.

Just one data point....

TJ
Click to expand...

...I am sorry to hear this and if you would like I will help you resolve the issues you are having. I boast regularly that we don't have any unhappy customers and prefer to keep it so. I suspect there is something different in your installation. At any rate, please feel free to give us a call so we can help. We have been manufacturing this product since early 1970s and have literally thousands in use. If you honestly are unhappy with your results you can also return the product for a full refund at any time. Thanks, Allan...:D
 
Thumbs up

I'm loving mine Sid. I have an O-320. The oil consumption has always been low and I don't notice any difference; but it certainly has cleaned up the plane's belly. I'm really impressed with that. Allan being so easy to deal with is icing on the cake. :D

Cheers,
 
Just ordered the kit. Can't wait to get it installed. The blow by on my IOX-360 is pretty bad. This should be a good test for the ASA kit.
 
There are four ways oil leaves the crankcase: 1: past the rings and into the exhaust, 2: out the breather in the form of mist, 3: past the valve guides, and 4: leaks at seams.

One drip a second ends up being a considerable amount of oil.

A large majority of the time oil gets out thru the breather because of the poor breather design inherent to Lycomings. But in the other cases, a separator will not help. So just because a separator doesn't solve the problem, doesn't mean the separator isn't working effectively.
 
Follow-up

I appreciate the feedback, gang. My separator arrived the other day, and I'm installing it today. It'll be a while (months?) before I start the engine, but I'm looking forward to the clean belly.

Allan, the white powder coat and blue tubing are going to look great under N260KM's hood. :cool:
 
rocketbob said:
There are four ways oil leaves the crankcase: 1: past the rings and into the exhaust, 2: out the breather in the form of mist, 3: past the valve guides, and 4: leaks at seams.

One drip a second ends up being a considerable amount of oil.

A large majority of the time oil gets out thru the breather because of the poor breather design inherent to Lycomings. But in the other cases, a separator will not help. So just because a separator doesn't solve the problem, doesn't mean the separator isn't working effectively.
Click to expand...

...Actually it does help in several ways. First, the separator catches oil exiting the breather. Second, with the vacuum evacuation valve installed, the lower pressure in the crankcase considerably reduces the windage, thus reducing oil vapors destined for the breather or separator. This lower crankcase pressure also helps seal and keep oil from passing by the piston rings as the differential is always in favor of the crankcase unless the throttle is pulled back. The reduction in crankcase pressure also has a dramatic effect on oil passing through the valve guides. The differential pressures on the intake guides become a standoff at cruise power settings and the exhaust guides stop passing oil when any power is applied. This eliminates the problem with Lycoming engines coking up the exhaust guides and sticking valves. (See Service Bulletin No. 388C) This has been an ongoing problem and has had much attention in the past. We have never seen an engine with the evaluator system installed show any signs of this issue. Also any oil leaks that fall into the seepage category are usually eliminated (when engine is running) as the cc pressures are reduced they become inward air leaks, rather than outward oil leaks. With throttle applied, you could remove the drain plug and oil would not come out. I will concede, we have been unsuccessful at making a separator that can stop oil leaks while the aircraft in parked, engine off, but we will keep trying. Some other advantages of this system include eliminating the possibility of the breather freezing up in cold weather. Another very important advantage is, with lowered cc pressure, any moisture present in the engine boils off at a considerably lower oil temperature and is carried off to the exhaust stream....:D
 
PerfTech said:
With throttle applied, you could remove the drain plug and oil would not come out.
Click to expand...

lurk5.gif
 
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Special one for an IO-540

Allan,

So I didn't see the answer in the posts above.. Is there a special size oil seperator that you make for the RV-10 (i.e. Lycoming 540)?
 
ppilotmike said:
Allan,

So I didn't see the answer in the posts above.. Is there a special size oil seperator that you make for the RV-10 (i.e. Lycoming 540)?
Click to expand...

...Yes ! the model for the 540 is different, and is 2.5" dia. instead of the 2.0" like the four cyl. models. Sorry, I must have missed that. Thanks, Allan....:D
 
clean down under

I am no longer going to dread the creeper and oily rag. (AND that darned bent whip antenna that always wants to put my eye out.... worse than a daisy BB gun)
The drain from my oil separator is now introduced to my stainless exhaust pipe. They can continue to get to know one another for a long time. A month of busy flying with the Antisplat saddle clamp and blue hose feeding any bypass into the hot gas stream, and the belly is sparkling white. These are such great little planes. Doesn't seem right to dribble oil and yuck anywhere on them. Just my observation.
 
DanH said:
Mike, you devil.

Case pressure on mine measures 2.5 to 3.5" Hg negative, 1.2 to 1.7 psi.

Allan, are you getting more than 3.5" Hg?
Click to expand...

...Yes Dan we are seeing higher numbers, but this requires some clarification. It is almost impossible to measure this with any conventional means that most people will have at their disposal. A vacuum gauge is worthless for this task, a magnehelic mechanical instrument is also useless as neither can react to the extremely high cycle rate (170 spikes per second). Any reading you gather will only reflect the low side of the pressure spike. A standard low cost digital manometer will do a little better, but they can't react that fast as well and are so dampened the readings for this purpose are useless. We gathered the information with our quartz pressure transducers from our dyno cell. These are very accurate and can read thousands of times faster thus providing all the information so the pressure spikes can be averaged, providing an accurate reading. We used this method to map what actually takes place in the cylinder of our racing engines at 8,500 rpm. wide open throttle. We gathered and mapped cylinder pressure readings every degree of rotation for 720 degrees of rotation or one complete cycle. When measuring crankcase pressure fluctuations, one would think all would be self canceling, as one piston is moving upward and another downward. This is not the case. The piston speed is much faster over the top of the stroke than at the bottom. This differential works wonders for our purposes. The pressure waves created allows us to use then as a pumping force to evacuate the crankcase. This in conjunction with the bias cut tube in the exhaust stream can produce numbers as high as 5.5" Hg negative. This piston speed differential and windage reduction is also responsible for the HP gains we have recorded on the Lycoming and Continental aircraft engines. Sorry! Looks like I am beginning to ramble! :eek:
 
PerfTech said:
The piston speed is much faster over the top of the stroke than at the bottom.
Click to expand...

Having trouble grasping how this could happen???????

Assuming zero piston pin offset, and the cyl bore is normal to, and not offset from crank center line, then piston lineal speed (not mean speed) is highest at mid stroke, is zero at TDC and BDC, and is either accelerating (moving toward mid stroke) or decelerating (moving away from mid stroke) between, depending on where in the rotation the crank pin is.

If I am wrong, please explain.
 
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Mike S said:
Having trouble grasping how this could happen???????

Assuming zero piston pin offset, and the cyl bore is normal to, and not offset from crank center line, then piston lineal speed (not mean speed) is highest at mid stroke, is zero at TDC and BDC, and is either accelerating (moving toward mid stroke) or decelerating (moving away from mid stroke) between, depending on where in the rotation the crank pin is.

If I am wrong, please explain.
Click to expand...

Hi! Mike; Due to my obvious lack of typing skills and laziness have a look at this link. It does a good job of explaining the piston crankshaft and rod ratio relationship. Thanks, Allan
http://www.epi-eng.com/piston_engine_technology/piston_motion_basics.htm
 
Allan, thanks for the link------best explanation i have ever seen for the subject.

I am aware of the effective shortening of the rod as the crank pin moves away from cylinder C/L--------and the effect it has on piston motion.

Same thing happens on the up stroke, which is not discussed in the linked data.

Still does not explain your statement of "The piston speed is much faster over the top of the stroke than at the bottom."
 
Mike S said:
Allan, thanks for the link------best explanation i have ever seen for the subject.

I am aware of the effective shortening of the rod as the crank pin moves away from cylinder C/L--------and the effect it has on piston motion.

Same thing happens on the up stroke, which is not discussed in the linked data.

Still does not explain your statement of "The piston speed is much faster over the top of the stroke than at the bottom."
Click to expand...

...Assuming a constant rotational speed in degrees the key statement is in this paragraph and illistration.


Figure 3: 90? After TDC

It is important to understand that the motion of the piston within 90? before and after TDC is not symmetric with the motion 90? before and after BDC. The rotation of the crankshaft when the crankpin is within 90? of TDC moves the piston substantially more than half the stroke value. Conversely, the rotation of the crankshaft when the crankpin is within 90? of BDC moves the piston substantially less than half the stroke value. This asymmetry of motion is important because it is the source of several interesting properties relating to the operation, performance and longevity of a piston engine.
 
All this conversation has caused me to rethink and replace my existing oil separator and with that, I wonder how hard would it be to install the 90 degree fitting into the accessory case in an installed engine. The space back there is very tight and the 90 fitting makes it even harder.

I suppose I need to look for that plug to see where exactly it is.
 
I'll be darned. I lurnt somtin new today.
(Sorry Mike S. I was on your team for a minute or two) Then I flopped like a catfish in the bottom of the john boat.
 
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Bavafa said:
All this conversation has caused me to rethink and replace my existing oil separator and with that, I wonder how hard would it be to install the 90 degree fitting into the accessory case in an installed engine. The space back there is very tight and the 90 fitting makes it even harder.

I suppose I need to look for that plug to see where exactly it is.
Click to expand...

... 99% of the separators and evacuation systems we sell are on existing installations. We can provide special fittings if necessary, but it usually isn't. At any rate, we will get it done. Thanks, Allan...:D
 
MarkW said:
(Sorry Mike S. I was on your team for a minute or two) Then I flopped like a catfish in the bottom of the john boat.
Click to expand...

No biggie----------I still contend that his statement is wrong. What I think he meant to say is correct, but it is not what he did say.

If he had talked about the piston speed leaving TDC is greater than the piston speed approaching BDC I would have to agree (if you read the linked info carefully, you have to conclude the inverse is also true)

But he said it is higher "over the top"----------and you cant go over unless you start before TDC.

Semantics............................ http://en.wikipedia.org/wiki/Semantics

TRUE_piston3_ANI.gif
 
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Mike S said:
No biggie----------I still contend that his statement is wrong. What I think he meant to say is correct, but it is not what he did say.

If he had talked about the piston speed leaving TDC is greater than the piston speed approaching BDC I would have to agree (if you read the linked info carefully, you have to conclude the inverse is also true)

But he said it is higher "over the top"----------and you cant go over unless you start before TDC.

Semantics............................ http://en.wikipedia.org/wiki/Semantics
Click to expand...

...Mike you are correct, I worded it wrong. I should have said, piston speeds over the top 180 degrees of rotation are considerably fasted than the bottom 180 degrees. I guess I got a little ahead of myself.
...Sorry I missed the ice cream social as I was looking forward to talking with you. I went to the Ramona BBQ first with intentions of going to both and time just didn't work out for me. Obviously we both need ice cream & BBQ....:rolleyes: I will be there next time. Thanks, Allan
 
PerfTech said:
We used this method to map what actually takes place in the cylinder of our racing engines at 8,500 rpm. wide open throttle. We gathered and mapped cylinder pressure readings every degree of rotation for 720 degrees of rotation or one complete cycle.
Click to expand...

You never have mentioned the name of Anti Splat's sister/parent/cousin company. That would be Performance Techniques (http://turbocharged.com/main.htm)? Are there others? I know we would all like to hear more about the company, the race engines, and a very impressive dyno setup.
 
Love it.

Back to the original question...

I love it.

Clean belly, low rate of oil consumption. It just works. :)
 
Air oil seperator

Installed the anti splat air oil separator. Before install belly was very oily. Oil consumption was about 1 qt in 6 hrs. Just flew to sun and fun. Total time after installation 11 hours. Belly is now clean except for a few residual streaks from the corners. Oil consumption was 1/2 qt in 10 hours... Wow. Great product

Toby
 
airtoby said:
Installed the anti splat air oil separator. Before install belly was very oily. Oil consumption was about 1 qt in 6 hrs. Just flew to sun and fun. Total time after installation 11 hours. Belly is now clean except for a few residual streaks from the corners. Oil consumption was 1/2 qt in 10 hours... Wow. Great product
Click to expand...
Good to hear it worked for you, Toby. Is this just with the separator or also with the vacuum valve and exhaust pipe saddle as well?
 
Just finished the installation of my ASA oil separator and vacuum valve on my RV-8 TMX 0360. I was impressed with the quality of the components.

Installation is pretty straight forward. It took longer than anticipated (isn't this always the way) since there is not much room between the rear of the engine and firewall. I had to remove more items than anticipated so I could have room to work.

Summary of steps: Remove old breather line, remove right mag, remove exhaust pipe, heat muff, scatt tubing, and anything else in the way....... remove plug on the rear accessory case. Install AN fitting, mount separator on firewall, drill oblong hole on exhaust pipe, mount vacuum valve, connect all lines, install and time mag, clean up and secure all lines.

The only glitch I ran into was that I was unable to install the supplied 90 degree AN fitting on the accessory case due to engine mount interference. Fortunately I had a spare 45 degree fitting that worked nicely.

I left the clamp off at the oil separator where the line is connected to the crankcase. In the unlikely event the vacuum valve malfunctions or a blockage occurs, I am hoping the line will blow off the oil separator rather than have the engine blow a seal.

Cleaned the belly, went flying, did some light acro and landed. Belly was still clean. Just in time to send the plane to the paint shop!
 
I have installed the ASA product, including the exhaust valve. After 50+ hours it is working as advertised. My oil consumption is down and my belly is clean of any oil. No more oil leaks in the engine compartment. I do periodically check the one-way NAPA valve by blowing into the oil dipstick tube to verify it is working properly.
 
Hi Guys,

Sorry this comes a bit late, but I thought I would share.

I would recommend that you inspect the check valve frequently for function and also blockage.

My check valve failed after 80 hours, the rivet that holds the assembly together broke and allowed the internals to fall and block the exit, there was no immediate increase in oil pressure, however the oil sludge then built up around the components and carbonised causing a complete blockage which blew the crankcase seal out of the front of the engine, what the time period was between failure and complete blockage, I can't exactly be sure, luckily I was close to the airport when I noticed a distinct burning smell.

After landing the sides, bottom and inside of the cowl and firewall of the RV where covered with oil, it was a real mess.

When I topped up the oil it needed 0.5 a quart to bring it back up to 6 quarts which is what I normally keep my oil level at, so I was lucky to not have ejected very much oil or damaged the engine.

I cleaned up the mess, cleaned and reinstalled the seal as per the appropriate lycoming instruction and have had no issues or leaks in over 60 hours, so all good here.

Allan sent me a replacement valve free of charge (their service is fabulous) and commented that they had only had 1 or 2 other failures.

I guess the message is check this component very carefully and more frequently to ensure that it is still functioning, otherwise on a long trip you could be caught out and have a very expensive engine failure.

Regards,
 
Whistle Slot?

A whistle slot was sometimes cut in the old style breather tube to bypass a blockage if one did occur. For these ASA oil separator installations should we be cutting a whistle slot in the hose to / from the separator to prevent this type of blow out?
 
A whistle slot is not recommended on the ASA setup. To help mitigate any damage to the engine seals in the event of a blockage I removed a hose clamp from the hose where it contacts the oil-air separator. I am hoping that the hose will blow off of the oil-air separator before an engine seal blows.

Open to other options. Any other suggestions?
 
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