[Cman]

Took the car to a buddy of mine that owns his own auto shop to show him the car. He liked. We were talking about the engine in it and when he noticed it was the Skyactiv engine he commented about maybe putting an oil catch can on it to collect the oil from the PCV system that would end up in the combustion chamber and be burned along with the air and fuel.

I didn't think these engines or any regular 4 cyl. type engines need a catch can. I do however use one in my Z06 and Shelby as those engines are known for sucking oil through the PCV and diluting the air/fuel mixture when it is burned. This can cause knock and reduces power. On the Shelby the oil can get bad enough where it will coat the intercooler and reduce boost and ultimately just makes a total mess inside the intake tract.

So is my friend right does this engine need an oil catch can? If it does who makes one for the 2.0L Skyactiv engine?

Tony

 

[Cman]

found this:

There?s Nothing Positive About the 2.0L SkyActiv PCV System! | JBR Blog

 

[Snoogie]

To be honest I've had a few cars come in with a catch can of various designs and brands fitted to these skyactiv engines and I will agree that it will help keeping oil from contaminating the intake valves and such. We had a few cases at the shop I work at where a full cleaning was needed to clean out sticky valves that would through drivablity codes. I'm actually planning on fitting one from corksport or anyone else who makes a decent functional catchcan. Those engines I've seen with catchcans fitted have a lot of oil collected between oil changes (about 3 tablespoon). In my opinion if you can afford a quality catchcan then go for it.

 

[Cman]

Well, would the ones they sell for the Mazda 3 fit on the engine for the CX-3?

I find the price for these to be absolutely ludicrous. US$185 for the JBR one and US$234 for the corksport one. It's just a frickin can with some hoses attached to it and the engine venting oil vapours. The ones I bought for my Z06 and Shelby weren't anywhere close to those prices.

I should just pick up another one for a Z06, fab up a bracket and get some fuel resistant hoses and get one on my car for way less.

Tony

 

[anchorman]

I'll just settle for using high grade fuel and oil. That write up by the company that makes money out of fitting such devices is hardly going to be negative about their worth.

 

[Cman]

I agree the article would be a bit biased since they are selling an item due to an issue they deem could be a problem with this engine, and using high grade gas and oil in your car isn't going to prevent this. However if this engine is known to suck oil vapours into the intake tract (it looks to be the case with the little research I've done since yesterday) then it probably is a good idea to get something like a catch can to prevent that.

I'm going to look into this, and I just might fab up something with the catch can from one of my other cars and see if I can make it work in this engine.

Tony

 

[santa]

I think I'll trust that Mazda thought about this when they designed the Skyactiv engines:
13:1 Compression and 40 mpg on 87 Octane fuel? Introducing Mazda?s Skyactiv Technology

Quote from page 6: "To eliminate the problem of intake valve deposits that plague current direct gasoline injection engines, the engineers at Mazda determined that deposits are formed when intake valve temperatures fall below 400 degrees C. Measures were taken so that the intake valve would operate above this point to reduce deposit formation."

"One of the biggest issues with direct injection engines is a build up of deposits on the intake valve. Mazda determined that this was largely due to the intake valve being too cool. A lot of analysis went into designing the heat paths away from the valves to keep them at the proper temperature to avoid deposit formation."

 

[DJ9999]

I'm in the camp that maybe .01% of buyers will install a catch can on this type of vehicle. Those other owners will not have any appreciable differences over those who have installed one. Not looking to debate, coming from Mazdaspeed forums, I know people feel strongly one way or the other.

It does provide good peace of mind to the weekend garage mechanics of the world.

 

[Vdubber]

I know this is an older post, but I agree with these motors needing a catch can. I just tore apart a skyactiv g 2.0 because of carbon build up and am installing an OCC when i put it back together. This car was throwing out crazy codes due to the build up. To the point the dealership recommended the engine be replaced LOL...tore it down just to make sure nothing was damaged inside the engine.
Here are a couple of pics. Not as bad as I thought, but it must sensitive to it.

 

[TORQUERULES]

That actually isn't too bad. A good synthetic that works nicely with DI engines, such as Pennzoil Platinum, would have went a long way towards preventing that. Plus a good "Italian tune-up" every once in a while.

Of course I am just guessing, but it looks like it was just around town driven and used sub-par oil (the build up is caused by the oil that gets through the valve seals to lubricate the valves coking and not being cleaned by fuel since DI injectors are not in the intake tract).

I have seen non-DI engines worse than that.

I catch-canned my Mazdaspeed, but it was built before manufacturers worked to prevent this coking with tuning to help minimize it. Of course it is still going to happen, but not anything like the early days of DI.

Use good oil, change it often, run the piss out of it every once in a while, and a good DI valve cleaning treatment every now and then won't hurt either. It's no cure-all, but it can't hurt.

 

[Vdubber]

Yeah I got this for a great price. It was used for a delivery service. No maintenance was ever followed. Now that it 8s back to new and in my care it will be well taken care of. I prefer the Mobile 1 oil. A Mazda tech gave me an exact rundown of how to to the carbon cleaning from now on.

Thanks for the new info
D

 

[Cman]

So that 3rd picture is that after you cleaned up the valves and head??

Torquerules..................LOL @ "Italian tune up"

 

[Vdubber]

Yeah this was drivin in amd out of a busy city. "Italian tune ups" were a regular occurence. Doesn't do a thing without regular carbon removal maintenance. I had to physically scrape chunks of carbon from some of the valves. That was just one valve, and not the worst one. Basic maintenance by removing the intake manifold and using a carbon removal product followed by an oil change will prevent this from happening again. I got the car for $300 so I didn't mind spending only 5 days making sure nothing was broken. Especially since the dealership mechanic was told over the phone by Mazda to just replace the engine.

 

[Vdubber]

Yes 3rd pic was after a quick cleaning. I used Arrow Magnolia Carbon X. Just made sure there was no internal damage and put it back together.