DIY: Dual Catch Cans with Air/Oil Separators... On the CHEAP!

DIGItonium · 11-23-2015, 02:19 PM

The new hoses eliminated the oil mist build up and leaks at the PCV. Now next issue: the Godspeed catch cans. These things leak all over the place, and is probably the culprit of 95% of the vacuum leaks. I've been hearing a hissing sound, and I thought it was the air flowing through the barb into the cans. Turns out it was the clear hose on the side of the can acting as a gauge. I temporarily taped it up, and it fixed some of the surging issue. Later that afternoon the surging got worse again. I did a feeler test on the cans to see where else the hissing is coming from and felt vacuum in the screw hole holding the aluminum block to the can.

I ended up taking taking the cans out, removed the screw, added high temp RTV, tightened real right, and then filling the holes with JB Weld epoxy. Then I tried using RTV all over the ends of the clear tubing. Lastly, I applied JB Weld all over the aluminum block. I even retorqued the barbs as it was getting loose as well (RTV didn't seem to hold up).

As a result, the surging reduced dramatically and at times would idle stable. However it started surging again after awhile, but not as bad or enough to throw a code. I found out there's still a hissing sound on one of the cans, but I haven't pin pointed it yet.

You get what you pay for with these cheap cans that can't handle PCV pressure. I added RTV the first time only to find out more leaks. This is pretty much the reason why on reviewer said his car threw a lean code after installing the cans.

So the final verdict for the Godspeed cans:

YzGyz · 11-23-2015, 03:20 PM

You guys have a pic outlined or diagram of which line going where? I'm scared of pulling and putting things in the wrong spot. I'm planning to use a cheap air/oil trap for a compressor.

YzGyz

DIGItonium · 11-23-2015, 10:51 PM

It's really easy. The cans have 2 barb connections (for 3/8" inner diameter hoses recommended). Just look at the PCV hoses connecting from the PCV on the valve cover to upper intake manifold. You are essentially adding the catch can inline with the connections. There's probably more than one way to skin a cat like the single can setup.

I'm probably going to look at getting a pair of JEGS now knowing it's just $50/ea, and I already spent more than budgeted for this crappy setup.

YzGyz · 11-23-2015, 10:57 PM

My pvc is to atmosphere I think. Had to put that little air filter thing on when installed the BP turbo. Im not at mechanically inclined. I thinker but that's about it. Need more "direct" instructions to do thing right.

YzGyz

DIGItonium · 11-23-2015, 11:03 PM

Oh I've seen those filters attached to the PVC. So how about the 2 ports coming out the front of the upper intake manifold with your setup? It's normally in vacuum, which can pull pressure from the PCV.

YzGyz · 11-23-2015, 11:11 PM

I'll have to look. I'm not sure what I did. Lol. I don't remember.. I'm pretty sure I simply put back what I took off minus the vent filter. That's where I get confused. If the filter replaced a hose, where the hell did the other end connecting to that hose go.. �� that's why I want a diagram or super clear picture so I can follow and compare to mine.

YzGyz

lj909 · 11-24-2015, 01:50 AM

Where your breathers are was a tube going to the intake tubes. That made vacuum but now it's boost. So now there just venting to air

DIGItonium · 11-25-2015, 12:56 PM

I'm starting to wonder if my cheap Godspeed oil catch cans is having difficulty handling boost since the lines feed into the upper intake manifold. It's already not sealed that well out of the box, and the RTV and epoxy is probably not going to help much when it starts building up pressure. The JEGS air/oil separator apparently is rated up to 150 PSI. That's probably an important requirement... [sigh]

[EDIT] Nevermind on the JEGS because the poly carbonate housing will crack over time. I guess it's time to invest in a higher quality all aluminum catch can that can handle boost. Here's what I'm looking at: Mishimoto MMBCC-MSTWO-BK. I plan to use brass fittings with Permetex Aviation Sealer for the threads.

YzGyz · 11-25-2015, 01:34 PM

I just bought a cheap H/F one for $9 to try out. I need to pick up one more later. I'm gonna try it as soon as I figure out how to connect it all.

3/8 in. Compact Air Filter

YzGyz

DIGItonium · 11-25-2015, 02:02 PM

Quote:

Originally Posted by YzGyz

I just bought a cheap H/F one for $9 to try out. I need to pick up one more later. I'm gonna try it as soon as I figure out how to connect it all.

3/8 in. Compact Air Filter

YzGyz

Nice! Uses the same 3/8" hose fitting. Let me know how it goes. This car is such a money pit with these little nagging issues with accessories.

SCOOBY JOE · 02-28-2016, 09:50 PM

Quote:

Originally Posted by YzGyz

I just bought a cheap H/F one for $9 to try out. I need to pick up one more later. I'm gonna try it as soon as I figure out how to connect it all.

3/8 in. Compact Air Filter

YzGyz

any updates? lol was thinking of doing the same thing to my car.

Ryguy · 03-08-2016, 03:02 PM

After reading through this tread and others about catch cans, I have a question that I couldn't find the answer too. It looks like there are multiple vents on both sides of the engine, the ones in front of the engine, which is where everyone is putting their catch cans that recirculate back into the intake manifold. But it looks like there is another vent above the middle cylinders that recirculates back into the intake piping. If that is a vent too, wouldn't the catch cans only filter half of of what is being recirculated back into the intake?

EVOHUNTER · 03-08-2016, 05:35 PM

DIY: Dual Oil Catch Cans 370Z

I used this for my reference, mine is a bit different as I have the stillen charger kit.

I took my 3/8's line off my PCV, attached that into the catch can "IN" and the "out" line off the catch can into the pcv. hope that makes sense.

Im running 2 catch cans, BTW.

Ryguy · 03-09-2016, 02:28 PM

That makes sense, however, it doesn't answer my question. I could be wrong but at least on my car, which I don't see why it would be different than anyone else's, there appears to be more than one vent on each side of the engine.

The red tube is what is replaced with all the catch can systems that I have seen, however, on the same location over the middle cylinders on each side, there is, what looks like, a vent and is recirculated back into the intake. So really my question is, does this tubing also act as a recirculation? And if so, wouldn't this also need to be connected to the catch can system?

EVOHUNTER · 03-09-2016, 06:58 PM

Quote:

Originally Posted by Ryguy

That makes sense, however, it doesn't answer my question. I could be wrong but at least on my car, which I don't see why it would be different than anyone else's, there appears to be more than one vent on each side of the engine.

The red tube is what is replaced with all the catch can systems that I have seen, however, on the same location over the middle cylinders on each side, there is, what looks like, a vent and is recirculated back into the intake. So really my question is, does this tubing also act as a recirculation? And if so, wouldn't this also need to be connected to the catch can system?

Don't worry about the other valve on the valve cover. that should be left alone. you only use the front PCV valve, don't touch the rear one.

Your red line, the Z1 one, it goes from your Valve cover to you intake manifold right? your catch can needs to be T'd into that line.

11-23-2015, 02:19 PM	#46 (permalink)
DIGItonium A True Z Fanatic Join Date: Jan 2009 Location: Kansas Posts: 3,800 Drives: 09 Z34-TT 6MT Rep Power: 42	Follow Up The new hoses eliminated the oil mist build up and leaks at the PCV. Now next issue: the Godspeed catch cans. These things leak all over the place, and is probably the culprit of 95% of the vacuum leaks. I've been hearing a hissing sound, and I thought it was the air flowing through the barb into the cans. Turns out it was the clear hose on the side of the can acting as a gauge. I temporarily taped it up, and it fixed some of the surging issue. Later that afternoon the surging got worse again. I did a feeler test on the cans to see where else the hissing is coming from and felt vacuum in the screw hole holding the aluminum block to the can. I ended up taking taking the cans out, removed the screw, added high temp RTV, tightened real right, and then filling the holes with JB Weld epoxy. Then I tried using RTV all over the ends of the clear tubing. Lastly, I applied JB Weld all over the aluminum block. I even retorqued the barbs as it was getting loose as well (RTV didn't seem to hold up). As a result, the surging reduced dramatically and at times would idle stable. However it started surging again after awhile, but not as bad or enough to throw a code. I found out there's still a hissing sound on one of the cans, but I haven't pin pointed it yet. You get what you pay for with these cheap cans that can't handle PCV pressure. I added RTV the first time only to find out more leaks. This is pretty much the reason why on reviewer said his car threw a lean code after installing the cans. So the final verdict for the Godspeed cans: __________________

11-23-2015, 03:20 PM	#47 (permalink)
YzGyz A True Z Fanatic Join Date: Jun 2013 Location: Houston Posts: 1,449 Drives: 2010 Nismo Rep Power: 63	You guys have a pic outlined or diagram of which line going where? I'm scared of pulling and putting things in the wrong spot. I'm planning to use a cheap air/oil trap for a compressor. YzGyz __________________ http://www.the370z.com/members-370z-...gyzs-turn.html YzGyz

11-23-2015, 10:51 PM	#48 (permalink)
DIGItonium A True Z Fanatic Join Date: Jan 2009 Location: Kansas Posts: 3,800 Drives: 09 Z34-TT 6MT Rep Power: 42	It's really easy. The cans have 2 barb connections (for 3/8" inner diameter hoses recommended). Just look at the PCV hoses connecting from the PCV on the valve cover to upper intake manifold. You are essentially adding the catch can inline with the connections. There's probably more than one way to skin a cat like the single can setup. I'm probably going to look at getting a pair of JEGS now knowing it's just $50/ea, and I already spent more than budgeted for this crappy setup. __________________

11-23-2015, 10:57 PM	#49 (permalink)
YzGyz A True Z Fanatic Join Date: Jun 2013 Location: Houston Posts: 1,449 Drives: 2010 Nismo Rep Power: 63	My pvc is to atmosphere I think. Had to put that little air filter thing on when installed the BP turbo. Im not at mechanically inclined. I thinker but that's about it. Need more "direct" instructions to do thing right. YzGyz __________________ http://www.the370z.com/members-370z-...gyzs-turn.html YzGyz

11-23-2015, 11:03 PM	#50 (permalink)
DIGItonium A True Z Fanatic Join Date: Jan 2009 Location: Kansas Posts: 3,800 Drives: 09 Z34-TT 6MT Rep Power: 42	Oh I've seen those filters attached to the PVC. So how about the 2 ports coming out the front of the upper intake manifold with your setup? It's normally in vacuum, which can pull pressure from the PCV. __________________

11-23-2015, 11:11 PM	#51 (permalink)
YzGyz A True Z Fanatic Join Date: Jun 2013 Location: Houston Posts: 1,449 Drives: 2010 Nismo Rep Power: 63	I'll have to look. I'm not sure what I did. Lol. I don't remember.. I'm pretty sure I simply put back what I took off minus the vent filter. That's where I get confused. If the filter replaced a hose, where the hell did the other end connecting to that hose go.. �� that's why I want a diagram or super clear picture so I can follow and compare to mine. YzGyz __________________ http://www.the370z.com/members-370z-...gyzs-turn.html YzGyz

11-24-2015, 01:50 AM	#52 (permalink)
lj909 Track Member Join Date: May 2014 Location: Riverside Posts: 584 Drives: 40th 370Z Rep Power: 12	Where your breathers are was a tube going to the intake tubes. That made vacuum but now it's boost. So now there just venting to air __________________ PW 07 HR350Z R.I.P. Totaled by 82yr old woman 2010 40th Anniversary 370Z

11-25-2015, 12:56 PM	#53 (permalink)
DIGItonium A True Z Fanatic Join Date: Jan 2009 Location: Kansas Posts: 3,800 Drives: 09 Z34-TT 6MT Rep Power: 42	I'm starting to wonder if my cheap Godspeed oil catch cans is having difficulty handling boost since the lines feed into the upper intake manifold. It's already not sealed that well out of the box, and the RTV and epoxy is probably not going to help much when it starts building up pressure. The JEGS air/oil separator apparently is rated up to 150 PSI. That's probably an important requirement... [sigh] [EDIT] Nevermind on the JEGS because the poly carbonate housing will crack over time. I guess it's time to invest in a higher quality all aluminum catch can that can handle boost. Here's what I'm looking at: Mishimoto MMBCC-MSTWO-BK. I plan to use brass fittings with Permetex Aviation Sealer for the threads. __________________ Last edited by DIGItonium; 11-25-2015 at 01:25 PM.

11-25-2015, 01:34 PM	#54 (permalink)
YzGyz A True Z Fanatic Join Date: Jun 2013 Location: Houston Posts: 1,449 Drives: 2010 Nismo Rep Power: 63	I just bought a cheap H/F one for $9 to try out. I need to pick up one more later. I'm gonna try it as soon as I figure out how to connect it all. 3/8 in. Compact Air Filter YzGyz __________________ http://www.the370z.com/members-370z-...gyzs-turn.html YzGyz

03-08-2016, 03:02 PM	#57 (permalink)
Ryguy Base Member Join Date: Feb 2013 Location: Oak Harbor, WA Posts: 186 Drives: 11 Nissan 370z white Rep Power: 12	After reading through this tread and others about catch cans, I have a question that I couldn't find the answer too. It looks like there are multiple vents on both sides of the engine, the ones in front of the engine, which is where everyone is putting their catch cans that recirculate back into the intake manifold. But it looks like there is another vent above the middle cylinders that recirculates back into the intake piping. If that is a vent too, wouldn't the catch cans only filter half of of what is being recirculated back into the intake? __________________ 11 PW base 370z w/ Z1 25 row oil cooler, K&N typhoon short ram intake, Megan racing drift spec catback, Z1 CSC Elimination kit, Work Emotion CR Ultimate, akebono sport calipers, DBA rotors

03-08-2016, 05:35 PM	#58 (permalink)
EVOHUNTER Track Member Join Date: Jul 2011 Location: Edmonton, Canada Posts: 681 Drives: BOOSTED3-7-0 Rep Power: 15	DIY: Dual Oil Catch Cans 370Z I used this for my reference, mine is a bit different as I have the stillen charger kit. I took my 3/8's line off my PCV, attached that into the catch can "IN" and the "out" line off the catch can into the pcv. hope that makes sense. Im running 2 catch cans, BTW. __________________

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