PDA

View Full Version : oil catch can for a 2015 Audi s5??



s5dan
03-29-2018, 12:37 AM
Anyone out here selling a oil catch can?

Sazexa
03-29-2018, 01:16 PM
Try the classifieds section

volvofan
04-09-2018, 01:32 PM
One just popped up in classifieds. You know why? Because I just spent all f**king weekend making my own custom solution.

In a similar vein, does anyone need it to rain tomorrow in Massachusetts? If so, you're in luck because I'm about to go wash my car.

-Jon

Lizard 1
04-09-2018, 04:54 PM
What is the DIY version of this?

Ape Factory
04-10-2018, 07:16 AM
Don't waste your time, they don't really help in the carbon buildup department (sorry volvofan, I feel your pain!). It'll be more beneficial to change your oil every 5K. There are two other ways oil get onto the valves. First, past the valve guides and second, from valve overlap. Catch can doesn't work in either of those scenarios. I believe JHM did a lot of testing on the RS4's, which were notorious for carbon buildup in short order, and found nothing really helped. This included water/meth injection.

Audi's new cyclonic air/oil separator is much more sophisticated and works better than the older units pre-S5. I studied it's design quite a bit (Audi PDF) and it's function under different engine operating parameters is quite interesting and gives a bit of insight into the hurdles they had to overcome. A catch can is simply not sophisticated enough to make a difference long-term. You'll still need to carbon clean. Even if you were to vent to atmosphere, it wouldn't catch what drips down the valves or combustion byproducts during overlap.

Reggie
04-10-2018, 09:51 PM
Don't waste your time, they don't really help in the carbon buildup department (sorry volvofan, I feel your pain!). It'll be more beneficial to change your oil every 5K. There are two other ways oil get onto the valves. First, past the valve guides and second, from valve overlap. Catch can doesn't work in either of those scenarios. I believe JHM did a lot of testing on the RS4's, which were notorious for carbon buildup in short order, and found nothing really helped. This included water/meth injection.

Audi's new cyclonic air/oil separator is much more sophisticated and works better than the older units pre-S5. I studied it's design quite a bit (Audi PDF) and it's function under different engine operating parameters is quite interesting and gives a bit of insight into the hurdles they had to overcome. A catch can is simply not sophisticated enough to make a difference long-term. You'll still need to carbon clean. Even if you were to vent to atmosphere, it wouldn't catch what drips down the valves or combustion byproducts during overlap.

You are right nothing worked on the RS4s. Toyota added a injector in the manifold to inject a slight amount of fuel to clean the valves.

doug97gxe
04-11-2018, 07:13 AM
Catch Cans are usually required with Turbo Cars .. not so much with Supercharged Cars.. but it can't hurt anything.. back in the day i made a DIY one for my 350z with materials from Home Depot

pics are down but won't matter anyway its a different car

http://www.350z-tech.com/forums/141-how-articles/52192-how-homemade-catch-can.html

Ape Factory
04-11-2018, 07:43 AM
In this case, people are hoping it'll catch the evaporative volatile emissions from the oil in the crank case. EPA laws mandate the "air" be recirculated into the combustion chamber. Problem is, we're hurling this air which is mixed with a variety of sticky stuff at hot, dry valves. Over time, due to not being sprayed down constantly by gas, it sticks, burns and accumulates. Carbon buildup.

Fresh oil doesn't vape off as much (and doesn't have any combustion byproducts in it yet) which is why changing it sooner than 10K is beneficial (if costly).

But I do know what you're referring to concerning compressor blow-by (unfortunately) on turbocharged engines and you are right in that regard as turbos, especially a decade ago, had enough of a tolerance in the CHRA/shaft/seals that you'd often get oil in the intake side of the engine an accumulation of oil usually sitting in your intercooler. They're a bit better these days but it's still an issue. Depending on the design, superchargers usually contain their own lube source and it's not as likely to enter the intake tract.

doug97gxe
04-11-2018, 08:33 AM
In this case, people are hoping it'll catch the evaporative volatile emissions from the oil in the crank case. EPA laws mandate the "air" be recirculated into the combustion chamber. Problem is, we're hurling this air which is mixed with a variety of sticky stuff at hot, dry valves. Over time, due to not being sprayed down constantly by gas, it sticks, burns and accumulates. Carbon buildup.

Fresh oil doesn't vape off as much (and doesn't have any combustion byproducts in it yet) which is why changing it sooner than 10K is beneficial (if costly).

But I do know what you're referring to concerning compressor blow-by (unfortunately) on turbocharged engines and you are right in that regard as turbos, especially a decade ago, had enough of a tolerance in the CHRA/shaft/seals that you'd often get oil in the intake side of the engine an accumulation of oil usually sitting in your intercooler. They're a bit better these days but it's still an issue. Depending on the design, superchargers usually contain their own lube source and it's not as likely to enter the intake tract.

Ahhhh thank you for the explanation


Sent from my iPhone using Tapatalk

volvofan
04-12-2018, 10:01 AM
Yup, tracking on all the myriad of sources of carbon build-up... all great info above, too. I'm just hoping the catch can helps to slow the process down, not eliminate it entirely. I figured a water/meth injection system or an extra fuel nozzle in the intake tract would be about the only other way to mitigate/eliminate. I think JHM tried the latter at some point (JHM Carbonator (http://www.audizine.com/forum/showthread.php/454383-Carbonator)) but it didn't pan out?

I went overkill w/ my catch can... -12AN (3/4" ID) lines from BOTH valve covers feeding into a baffled .75L can, then out to the cyclonic oil separator. Used OEM connectors, braided nylon sleeves (to match the rest of the hoses that are part of the APR stage III kit), and heat shrink tubing to make it all look nice and neat. I ran a drain line with 1/4 turn ball valve down into the belly pan area so I could empty it without even popping the hood. If I had it to do over again, I would have only used -10 or even -8 coming from the valve covers, since there are two hoses instead of just the stock one, it would not cost any flow capacity and would have allowed me to use smaller (e.g. cheaper) fittings and hoses. As it was, I was about $200 all in for the parts.

-Jon

Ape Factory
04-12-2018, 10:37 AM
Very thorough! Any pics?

volvofan
04-12-2018, 07:09 PM
I had a feeling someone might ask, so I took some quick photos when I stopped to fill up.

The can originally had the three -12AN ports around the circumference of the can with a mesh breather filter on top. I cut off one of the three ports and installed it in the top where the breather was using drilled/tapped screws and JB Weld (and an o-ring for good measure) to seal. The hole left in the side of the can was easily tapped and plugged with a 1/2 NPT brass fitting.

Added bonus: while doing this maintenance, I discovered that the air pump foam filter inside my airbox completely disintegrated. I ended up plugging that airbox hole and cutting the hose back to the air pump fitting, then attaching the nice mesh breather filter that came with the catch can to it :) Otherwise, it would have gone to waste!


616286162961630

Ape Factory
04-12-2018, 07:13 PM
Sweet! Looks factory! Nice and tidy. I know there's not a lot of room to work with in there, especially with the addition of the supercharger.

volvofan
04-24-2018, 01:50 PM
Update:

I'm emptying every thousand miles or so. More frequently than I need to, for sure, but I don't have a dipstick or sight glass, so frequent maintenance is a must! Definitely more condensed water vapor than oily sludge... very runny, smells almost like gasoline. Still, glad it's not in my intake. I get maybe four to six ounces or so every draining (I typically do it at a fill-up, and grab a coffee cup or used plastic bottle out of the trash... haven't come close to filling one yet).

-Jon