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Oil Separator and Vacuum Valve

dlloyd3

Well Known Member
Several weeks ago I bought and installed an oil separator and a vacuum valve sold by Anti Splat Aero. They shipped the same day as ordered and the parts looked very good. I mounted the separator on the engine mount using Adel clamps, ran the inlet plumbing to the breather, outlet air to the vacuum valve. That valve I had welded in place by a local hot rod fabrication shop. An oil return line was obtained from TS Flightlines and teed in to the #3 valve rocker drain.
A quart of oil every 5-6 hours was either leaking, going out the breather, or being burned. Results after 10 hours are there is no new oil on the belly of my airplane. No oil is leaking from the bottom of the accessory case. The 10 hours began showing 7 quarts on the dipstick. Now it is down to about 6.5. It has been too hot and bumpy to determine any power increase due to the lower crankcase pressure. But that doesn't matter--the belly is clean!
There have been a couple of threads discussing the pros (several) and cons of using the vacuum valve in addition to a separator as well a a thread introducing Anti Splat Aero separator. Can't believe I waited this long.
 
Question

I just bought one also for my -10, it was shipped the same day. I have not installed it yet, but noticed that my O-540 has a 1" breather tube and the air oil separator is ?? . I looked and it appears the O/IO-540 engines have both 1 inch and 3/4 inch breather fittings.

If there is one available, I would rather change out the breather fitting to convert it to ?? rather than try to reduce the 1? fitting to ?? . Two questions:

1. Does anyone know the part number and where I can get a breather fitting that fits on the O-540 that is ???
2. If not, what is the best way to reduce the breather size from 1 inch to ???


Once I get it installed, I will report on how well it works. I currently use 1 quart every 3.5-4 hours. Plugs are clean, exhaust nice and clean (very light grey with no soot/residue), good compression, minor oil seepage in some areas, no dripping oil -- therefore it appears oil is being blown out through the breather). Hope to have the same results others are reporting.:)


Thanks -- TJ
 
Breather line

I just bought one also for my -10, it was shipped the same day. I have not installed it yet, but noticed that my O-540 has a 1" breather tube and the air oil separator is ?? . I looked and it appears the O/IO-540 engines have both 1 inch and 3/4 inch breather fittings.

If there is one available, I would rather change out the breather fitting to convert it to ?? rather than try to reduce the 1? fitting to ?? . Two questions:

1. Does anyone know the part number and where I can get a breather fitting that fits on the O-540 that is ???
2. If not, what is the best way to reduce the breather size from 1 inch to ???


Once I get it installed, I will report on how well it works. I currently use 1 quart every 3.5-4 hours. Plugs are clean, exhaust nice and clean (very light grey with no soot/residue), good compression, minor oil seepage in some areas, no dripping oil -- therefore it appears oil is being blown out through the breather). Hope to have the same results others are reporting.:)


Thanks -- TJ

...If you cant find a fitting locally, please let me know and we can make you an adapter and send it to you. Thanks, Allan:D
 
Type of Hose?

What kind of hose are people using to go from the breather to the separator? MIL6000 or some other flex line?

Hello Charlie
... We recommend a high quality silicone hose. If you cant find it locally we have it in stock and it is only about $5 a ft. If we can help please let us know. We are currently having steel braid oil return hoses made and as soon as they are finished we will be offering an installation kit. This will include three ft. of silicone hose, the four clamps, the oil return hose and fittings. We get many requests for this so we will offer them in a few days. Thanks, Allan...:D
 
Excellent Results for me also

I've also installed the Anti-Splat Oil Separator and check valve. I was getting a lot of oil out the breather and onto the bottom of the airplane and antennas. I normally only run between 6-7 quarts of oil so I'm not overfilling and blowing out the extra. I just cleaned the belly after having the separator installed for about 25 hours. Very little oil and it was so thin it didn't really need cleaning. I am super impressed how well the oil separator works. Since I'm not blowing so much oil out the breather my oil consumption went from about a quart every 7 hours to a quart every 15 hours or so.

I used the standard rubber hose that Van's ships for connection to the aluminum breather tube (new one that wasn't shortened yet - CV Hose 9816) for connection from vent to the inlet of the separator. I used an identical one with a longer tail (about 30" before trimming) to connect to the check valve on the right side exhaust. It had the pre-bent 90 which worked well to turn the hose out away from the battery at the oil separator before going down. Both hoses are available direct from Napa.

For the small drain connection out the bottom of the separator going back to the crankcase I used the same braided hose that Van's uses for the manifold pressure line (VA-102). Of course your mileage will vary for length depending on where you locate the oil separator. And you'll probably need a 3/8" to 1/8" brass pipe bushing to adapt to the 1/4" hose fitting for connection at the crankcase. It's probably difficult to find a 1/4" hose to 3/8" pipe fitting.

I had a friend weld the check valve to the exhaust at the proper angle. The installation was easier than expected. I was very impressed with the quality of separator and mounting bracket. As far as a power increase.... you're probably asking the wrong guy as I'm not sure I could tell the difference between a few more horses. That's not why I wanted to install it. Below are a couple photos of my install. I'm a very happy customer just like with the wheel bearing mod Allan provided.

OilSep1.jpg
OilSep3.jpg


OilSep2.jpg
 
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The silicone hose that Allan is using is much better than the heater hose that Vans is using. I use a convoluted teflon hose. Very flexible, withstands high temps, looks great. But, is more expensive than a clamped silicone hose.
Tom
 
INSTALL KIT!!!!!!!!

...Here is a photo of the items that come in the installation kit. Thanks, Allan..:D
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222.jpg
 
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Anyone see any problem using a copper reducer (from Home Depot) butted up against the 1 inch breather fitting using 1 " hose and 2 clamps and then using the 3/4" silicon hose I got from ASA for everything else?

No one has been able to tell me if I can use the 3/4" breather from an O-360 on an O-540.

Thanks -- TJ
 
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Anyone see any problem using a copper reducer (from Home Depot) butted up against the 1 inch breather fitting using 1 " hose and 2 clamps and then using the 3/4" silicon hose I got from ASA for everything else?

No one has been able to tell me if I can use the 3/4" breather from an O-360 on an O-540.

Thanks -- TJ

....No problem with reducing it down, or you can just buy a 1' male NPT x 3/4" push on hose fitting that will go right in the accessory case and then everything is 3/4" hose. Most 0-540 are 3/4" from factory but it seems I need to ask when we get an order for the 0-540 or include a fitting. We are very sorry you encountered this problem and if we can help please let us know. Thanks, Allan...:eek:
 
Alan, that is probably a good idea. I have a stock YIO-540 from Vans and it is a 1" breather. So I suspect MOST of the 540s will be 1" and only older engines or those that are rebuilt might have the 3/4". I'm not sure I've even seen someone with a 3/4" breather so far.
 
What is the maintenance requirement for the separator unit?
How do you clean & inspect it?
How long does it last?
I don't see a way to disassemble the cannister for cleaning?
I'd hate to do an oil change, and think the carbon trapped in the maize would be carried by the clean new oil back into the sump?
I'm not being negative, I think it's a better unit than the Airseps we use at work, and they can't be disassembled either. We just throw them away when they get clogged, because we can't slosh them out, and opening one would destroy it.
So fill us in on the life cycle manitenance?
 
New Fittings !!!

Alan, that is probably a good idea. I have a stock YIO-540 from Vans and it is a 1" breather. So I suspect MOST of the 540s will be 1" and only older engines or those that are rebuilt might have the 3/4". I'm not sure I've even seen someone with a 3/4" breather so far.

....We have made some fittings for this installation. Regards all, Allan...:D
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Cleaning

What is the maintenance requirement for the separator unit?
How do you clean & inspect it?
How long does it last?
I don't see a way to disassemble the cannister for cleaning?
I'd hate to do an oil change, and think the carbon trapped in the maize would be carried by the clean new oil back into the sump?
I'm not being negative, I think it's a better unit than the Airseps we use at work, and they can't be disassembled either. We just throw them away when they get clogged, because we can't slosh them out, and opening one would destroy it.
So fill us in on the life cycle manitenance?

...The life cycle in basically for life! This unit should last the life of your airplane and is guaranteed to do so. There is no carbon build up as the blow-by is only oil. The water vapor is sent over board, and oil is returned to the reservoir. We have never seen any build up in the unit itself. It will stay as clean as the inside of your crankcase. We do suggest if your engine has excessive blow-by, that when doing your annual inspection you loosen the clamp, remove the unit and rinse it out with solvent, gasoline or carburetor cleaner. There are no biodegradable parts or anything that can be hurt with even the most aggressive carburetor cleaners Etc. The separators are made of aluminum and have some stainless steel wire inside that can be swished and blown out with air if you desire. If you install the vacuum valve, we recommend at annual or 200 hours you unscrew the valve, stick a wire brush or small screwdriver in the 3" tube and remove any build-up inside the tube. We have only seen this on engines with no separator installed and an excessive amount of blow-by and oil consumption problems. Thanks, Allan...:D
 
Alan, has anyone used your install kit for the 540? Three feet of hose seems like it might be a little short to get from the left of the engine, curve around and then get to the right side of the firewall to connect to the separator. I haven't had a chance to measure yet, but it seems like that might be a little short.
 
Does anyone know where the return oil line from the separator would be connected on an O-360-A1F6D? Thanks,
 
Would there be an advantage (in performance or reliability) to having two vacuum valves installe...one on each pipe with a "t" connector to the separator?
Any down side, aside from weight?
 
Would there be an advantage (in performance or reliability) to having two vacuum valves installe...one on each pipe with a "t" connector to the separator?
Any down side, aside from weight?

No advantage just more expense and complexity. Thanks, Allan...:D
 
Alan, has anyone used your install kit for the 540? Three feet of hose seems like it might be a little short to get from the left of the engine, curve around and then get to the right side of the firewall to connect to the separator. I haven't had a chance to measure yet, but it seems like that might be a little short.

I did one myself and it was plenty for that plane. If you think you may need more just let me know. Allan...:D
 
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