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Catch Can Skeptic

CSI-WALLEYE
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CSI-WALLEYE Enthusiast

CSI-WALLEYE

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1 hour ago, Capt Bob said:

Well then in an effort to stay on point, it appears by this statement that if your engine is in good shape, you should have minimal oil in the blow-by gas so the question is.....

What constitutes "minimal"?

I read an article on emission system design that stated that an engine in fine tune should have a measured blow-by oil content of 1gram or less per hour under load. That would equate to a little over 3.5 ounces every 100hrs. if I did the math correct. One might want to measure the can droppings based on an hourly drain rather than mileage to see if they're in that ball park.

If the results are higher, then logic would indicate a poorly designed motor or bad sealing aka rings. I'm leaning toward the latter. If so then the use of quality oil and filter with consistent change times may provide just as much protection as the can itself. A lot to ingest and think about with these motors.

Sorry, I did not quite follow the part about the clean, high quality oil reducing the amount of blow-by.  Does the low quality or dirty oil interfere with proper seal or is it that they cause wear and eventually cause poor fit?

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L86 All Terrain
L86 All Terrain

GM installs catch cans on all boosted V8's, and perhaps even the LT1 cars if I am not mistaken. All LT4/5 cars are equipped with catch cans from what I have been told. So they have done the research,

MaverickZ71
MaverickZ71

Just think about all of this crap today.  Back in the day, a simple valve cover breather used to take care of everything.  But that's against the law now.  The more mankind 'progresses', the more we m

Nitrousbird
Nitrousbird

Or use simple logic.  If oil isn't hitting the valves, what would be building up on them?  Exactly.     If you reduce the amount of oil hitting the valves, common sense would tell you that y

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Capt Bob Enthusiast

Capt Bob

Posted
Posted (edited)
1 hour ago, CSI-WALLEYE said:

Sorry, I did not quite follow the part about the clean, high quality oil reducing the amount of blow-by.  Does the low quality or dirty oil interfere with proper seal or is it that they cause wear and eventually cause poor fit?

I'm not sure how well any type of oil acts as a sealant so yes I'm referring to premature wear and deposit buildup on the rings. Aside from a holed piston, blow-by gets into the crankcase in three spots. Between the cylinder wall and ring face/lands, the ring grooves on the piston and the ring gap itself. From what we are bombarded with about oil, the highest quality stuff contains an additive package to combat buildup of carbon in these areas as well as prevent excessive wear. That in turn helps keep blow-by at a manageable level or so it would seem. This of course predisposes that one renews (changes) this magical fluid on a regular and timely basis. There's the "rub" so to speak.

 

I'm still on the fence with this can but my interest has peaked with the thought of using it to monitor my blow-by amounts as the engine ages and to get a better feel on the emission designs built into this engine. A lot to ponder at this point.

 

Edited by Capt Bob
diyer2 Senior Enthusiast

diyer2

Posted
Posted

Hows this for a solution.

image.jpeg.9b2372af6db14923c4ae0693a5524e9a.jpeg

You call it.

 

:)

  • Haha 1
Jacoby Enthusiast

Jacoby

Posted
Posted
1 hour ago, CSI-WALLEYE said:

What can do you think is the best bang for the buck?

A homemade setup like BigBlue posted a couple pages back. If you want something name brand then I’d say the standard can from Elite Engineering 

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Gagliano7 Enthusiast

Gagliano7

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On 4/1/2019 at 9:46 AM, Silverado-Hareek said:

 

Agreed I don't think they care.  Their primary focus is selling vehicles and turning a profit.  Keep in mind, most manufacturers are using DI engines and none are using catch cans except in rare instances of high performance vehicles.  GM isn't going to spend the money on a catch can if their competitors aren't.  Again, the primary issue is that it requires the user to drain the can which most people don't even know how to pop their hoods much less drain an oil catch can and monitor the differences between cold weather and warm weather and how full the can is getting and so on.  And if someone forgets and the can fills up too much and the contents gets sucked back into the intake manifold, GM is on the hook for that design.  No, if GM (and all other manufacturers except Toyota) can get the DI engine to last past the warranty period, they're off the hook and they'll gladly sell you an engine cleaning service at that point as part of "routine maintenance."  I don't really blame the manufacturers completely.  This is evolving technology in response to regulations that mandate fuel economy.  However, now that manufacturers like Toyota are coming up with a fix or rather a design update to the platform, I do blame the manufacturers that don't follow suit and keep selling DI engines with this inherent design flaw.

My friend just bought a f150 5.0 and ford has a set of multi port injectors to clean the valves on there DI engines.

Silverado-Hareek Senior Enthusiast

Silverado-Hareek

Posted
Posted
44 minutes ago, Gagliano7 said:

My friend just bought a f150 5.0 and ford has a set of multi port injectors to clean the valves on there DI engines.

You're right I forgot Ford had been working on this as well.  It's a promising sign that manufacturers are catching on to the issue and coming up with solutions.

32 minutes ago, Jacoby said:

And GM will soon follow and do the same

Hopefully

Jacoby Enthusiast

Jacoby

Posted
Posted

I don’t think carbon buildup was a major factor in ford addding port injection with DI. The truth is Ford doesn’t have any claims of motor issues from premature carbon buildup. I don’t care what you find on YouTube. Ford has been running DI in the F series since 09. That’s millions of trucks with millions of miles and no mass claims of any motor problems from carbon buildup. I’m sure the whole washing the valves thing is just a by product or added benefit of adding PI. Truth is having both forms of injection adds more power and fuel efficiency and that’s why they did it.  I’d still run a catch can on a motor with both but that’s just me. 

Capt Bob Enthusiast

Capt Bob

Posted
Posted

That's like a tennis match with all the back and forth over there.

CSI-WALLEYE Enthusiast

CSI-WALLEYE

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2 hours ago, Capt Bob said:

That's like a tennis match with all the back and forth over there.

I think the discussion was more in-depth than this thread.

Morpheus Enthusiast

Morpheus

Posted
Posted

Unless you're foot is constantly in the gas on this thing, I don't think you'll truly need a catch can.  The pcv valve is spring loaded and will open and close based on crank case pressures.  Crank case pressures vary directly to rpm/load of the motor.  Also, there are tons of articles out where catch can systems can fail causing an over pressure of the oil system.  They end up with blow rear main seals among other items.  Its across the board with different vehicle makers, not just a GM thing.  

 

My advice, be diligent on research and form your own opinion.  Whatever you choose, I hope it works in your favor.  

Capt Bob Enthusiast

Capt Bob

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