Adding an Oil Catch Can/Accessing your Tophats

[NewZJ]

Maybe I need a catch can

 

[BoostedSnail]

i was told last time i got my oil changed that I had oil in the turbo and that they documented I have an after market exhaust and intake which altimately makes me believe they voided my warranty with that

 

[$ub$onic]

Did you see the oil yourself? Or just going off what they said

 

[BoostedSnail]

Did you see the oil yourself? Or just going off what they said

going off what they said but when i was on the dyno i saw a little white smoke coming off the turbo from the dyno.

 

[rdss]

This area is also home to your front struts. If you plan on installing coilovers or drop springs, you need to access the top hats to get your springs out.

Take a small screwdriver and pry up the caps on the windshield wipers.

Expose the 15mm nuts holding on the windshield wipers. Remove these and you can pull the wipers up and off. I used vice grips with one side of the jaw on the stud, and the other underneath the wiper arm to pry them off without visible damage.

On either end of the cowl are a rubber flap, a foam pad, and a nylon rivet

The cowl has 4 nylon rivets. Once these are removed, you can remove this piece by working one side, and then the other.

Here is the tophat for the driver strut. I've never seen a design that doesn't bolt in, so this is probably pressed into the body.

Removing the dust cover exposes the top of the strut piston. Using an open ended wrench, and really big Torx driver, you can unbolt the top of the strut from the car.

5 10mm bolts remove a firewall cover. Wires go through the cover to the windshield wiper motor, so I just moved it aside. I used an existing hole and an automotive bolt/spacer to mount the catch can mount to the firewall.

I'll see if I can dig up something else with the rest. The info here is all I needed for the RS suspension install that I installed.

 

[CjCsonic]

Very glad to be on the forum, this write up really helped and took the guess work out of adding my catch can. Preciate-ya!

 

[Macehammer]

The rivets, are they single use?

 

[rdss]

Most if not all rivets are single use and have to be drilled out when being removed.

 

[ChrisJ]

The other day I decided to pull the oil filler cap off with the engine running just to see what I could see going on and I could not believe the amount of vacuum at the cap.

Totally different than older style engines. I thought the only source of vacuum for PCV came from between the air cleaner and the turbo? How could this produce such a strong vacuum in the valve cover at idle? It also caused it to idle rough due to the bad vacuum leak which is no surprise.


I'm assuming the throttle body is in between the engine and the turbo so the air cleaner side should be wide open?

 

[$ub$onic]

My 1.8 Is the same way. I don't know the exact reason why but my theory is to keep the crank case totally vapor free. Also a loose dipstick will cause the rough idle to

 

[ChrisJ]

My 1.8 Is the same way. I don't know the exact reason why but my theory is to keep the crank case totally vapor free. Also a loose dipstick will cause the rough idle to

Oh I know that but where is it coming from? I'm curious of how its actually doing it. Is there more than one suction point besides between the air filter and the turbo?

 

[$ub$onic]

I'm assuming its like any other crank case evap and its using the vacuum of the motor. Where it gets it comes from I have no clue. Gas motors do make a rather large amount of vacuum though

 

[RS Turbo]

The PCV System is Sealed in these engines. That is why there is an O ring on the dip stick. This is Normal.

 

[austinw24]

Sorry to dig up an older thread on here, since there was so much debate on oil catch cans and their worth; I was cruising the cruze (see what I did there) forums and found this:

Originally Posted by Vince
I think it is a very smart investment. In fact, my Cadillac ATS has a contraption on it that resembles the factory’s effort at implementing a catch can.

There are actually two ways oil can contaminate the intake tract on these engines. When the manifold is under vacuum, the PCV vapors are ingested right at the manifold, but obviously this doesn’t work under boost. The check valve in the line to the manifold prevents boost from going into the crankcase, and instead crankcase vapors are routed to the turbo’s compressor inlet. This means anything that comes out of the crankcase will go through the turbo and collect in the intake tract. Eventually this oil can contaminate the intake manifold, intake valves, and even piston heads.

I think it is very wise to put a catch can in between the crankcase line that goes to the turbo compressor inlet to prevent the oil and vapors from going through the turbo. I’m not sure you need one on the other side that goes into the intake manifold, because there isn’t likely to be much crankcase pressure when the engine is under vacuum. All of GM’s factory turbocharged engines, tuned, or not, if driven aggressively can accumulate oil in the intake tract, and it’s obvious they tried to address that issue on the Cadillac ATS. The earlier engines, like the LNF, LHU/LDK and the LUJ/LUV have no mechanism to collect oil from the PCV system and in fact the Cobalt SS owner’s manual says to expect increased oil consumption with aggressive driving. I guess they mean in the intake tract! ;-)

(source: Oil catch can explained (read if tuned) - Page 3 )

That is Vince from Trifecta commenting on the catch can and its ability to benefit the engine.

BUT... As with any aftermarket modification, it must be done right. The same person who wrote the tutorial on that thread also posted this:
WARNING!!! Catch can fail

DO NOT BUY CHEAP STUFF FROM EBAY.
Here is an explaination of the insides of a good catch can from BT (They make billet parts for LX body dodges):
The Original Catch Can | Billet Technology


Personally, I have always had one on my engines and will be installing a catch can along with a check valve as soon as the valve gets here.

 

[aforce1jp]

What size fittings are required to connect a catch can to the stock PCV hose? Thanks a lot.
James

 

[law242]

I'll sell you my direct fit unit I made, look earlier in the thread for my pics

 

[94383Z71]

law, did you ever decide about building units like yours for a price? and to that end, would they have a baffle in the can as Preloader mentioned?

 

[94383Z71]

Well I guess that's a no. I've got oil at my turbo inlet and feel it would be beneficial to have one of these setups. Need to find a quality system to install.

 

[mja]

just installed a saikou michi oil catch can. high quality stuff.
and yes these pcv valves leak oil pretty bad:

(will get a less blurry pic sometime)

Didn't need to take the cowl off at all if you install on the strut well in this position.

..If you go with Saikou, be prepared to wait 2-3 months. but their products are top of the line. Also contact me and I'll get you better measurements for the custom job. The inlet angle is perfect, the outlet angle needs to be changed 60-90 degrees toward the motor so the hose doesn't interfere with the stock airbox. Shouldn't be a problem when it's upgraded to an aftermarket intake.

A note - I only use Royal Purple full synthetic oil in my cars, sometimes Mobil 1. This leaking is irrespective of the quality of the oil used. Also I replaced my PCV valve not even a year ago, so there's only about 5,000 miles on this valve. Meaning it doesn't matter the condition of your PCV valve it's going to leak.

 

[mja]

What size fittings are required to connect a catch can to the stock PCV hose? Thanks a lot.
James

5/8"

If you cut the plastic corrugated hose at the position where it's heat shrunk to the PCV valve connectors which is easy enough just with a knife, you'll be able to shove a 5/8" hose with a good amount of force and it'll fit snug.

If you can find (or custom order) a catch can with 5/8" fittings this will make the install easy and clean looking. Buy low pressure fuel hose (don't need the expensive fuel injected stuff), not vacuum hose. 5 feet is enough to mess up and have an extra long section for a redo.