Pcv Catch Can Installed

cujo8 · May 3, 2011

The longer air hose should be looked at as restricting the air flow of the vent, not limiting airflow to the manifold. A longer hose and some homemade catch cans can possibly restrict the flow to the point were the crankcase can build enough pressure to cause problems.

Well Snakedoctor has been using the AMW Catch can kit for 5 years without any problems according to him, so that is a pretty good track record.

Mossyoakglock · May 3, 2011

For those with a catch can, how warm does yours get?

I drive about 15 miles to work every morning and when I touch the can it's warm. Not hot but warm to the touch. I figured it would be a little warm since it's hot oil vapor.

cujo8 · May 3, 2011

For those with a catch can, how warm does yours get?

I drive about 15 miles to work every morning and when I touch the can it's warm. Not hot but warm to the touch. I figured it would be a little warm since it's hot oil vapor.

I checked my catch can after a 24mile trip home from work and it was cool to the touch, but mine is mounted on the inner fender above the aux. battery tray far from the engine.

BigBlueLB756 · May 3, 2011

If the catch can is collecting oil residue, then the flow of air through it is sufficient for the PCV system to work. If you're not getting goo, you're not venting to the intake.

dewfpo · May 3, 2011

The longer air hose should be looked at as restricting the air flow of the vent, not limiting airflow to the manifold.

That's a good point. Above idle the airflow to the engine is limited by the throttle body and any 'potential' reduction in air volume thru the PCV line would be made up through the throttle. I guess the only time the air intake volume 'might' be affected would be at idle when the throttle is closed and vacuum is high, but as others have said it would probably be negligible (less than a few %).

Thanks for the discussion guys.

DEWFPO

kdixer · May 4, 2011

The longer air hose should be looked at as restricting the air flow of the vent, not limiting airflow to the manifold. A longer hose and some homemade catch cans can possibly restrict the flow to the point were the crankcase can build enough pressure to cause problems.

Well Snakedoctor has been using the AMW Catch can kit for 5 years without any problems according to him, so that is a pretty good track record.

Snake Doctor comes off as the kind of guy to do his homework on a project such as this. I am not questioning his work at all. I am just pointing out that it is not as thoughtless as putting any old plumbing project in to perform this job. Idealy you want the fittings to be as close to the size of the stock breather tube as possible to insure proper air flow for the vent to do it's job. You would not want to install undersize fittings just to get something to fit. And ideally if you go with the homemade setup, make sure the inlet passages on the oil seperator are sized correctly. I mean after all, many homemade setups use filters designed for 120+ psi air compressor systems. An engine can see some serious leaks from just a few psi.

My response was strictly for the concerns of if it could affect airflow. And it certainly can. But not so much as a "not enough air entering the intake" standpoint. It would be more of a "not enough air leaving the crankcase" stand point.

kdixer · May 4, 2011

Quick question for you catch can guys. Do you do anything to the breather hose connecting the passenger side valve cover to the intake tube or just the one from the drivers side valve cover to the Manifold?

dlstewart01 · May 4, 2011

Yeah, old snakedoctor has done his homework a time or two having restored motorcycles then autos frame up for over 25 years. Now I'm just old and crotchety and enjoying it..

dlstewart01 · May 4, 2011

Quick question for you catch can guys. Do you do anything to the breather hose connecting the passenger side valve cover to the intake tube or just the one from the drivers side valve cover to the Manifold?

The breather hose on the passenger side is a fresh air hose. It replaces the air in the crankcase as it is purged by the PCV.

http://www.mightyautoparts.com/pdf/articles/tt122.pdf

Mossyoakglock · May 4, 2011

Mine was not cool to the touch but not hot either, just warm. Yours might be cooler being on the fender wall and gettin g more direct airflow. With mine being behind the grille I don't think it's getting as much direct airflow because of the angled plastic that channels air into the radiator.

For those with a catch can, how warm does yours get?

I drive about 15 miles to work every morning and when I touch the can it's warm. Not hot but warm to the touch. I figured it would be a little warm since it's hot oil vapor.

I checked my catch can after a 24mile trip home from work and it was cool to the touch, but mine is mounted on the inner fender above the aux. battery tray far from the engine.

Mossyoakglock · May 4, 2011

If two people had the same catch can but with different hose lenghts and mounting locations and one was catching more goo than the other, what would be the reasoning for one catching more than the other if they had the same diameter hose and can but the only different was hose length?

Would it be better to have longer hoses or shorter hoses?

If the catch can is collecting oil residue, then the flow of air through it is sufficient for the PCV system to work. If you're not getting goo, you're not venting to the intake.

dlstewart01 · May 4, 2011

I believe the hose length will have little bearing on the performance of the PVC system, if kept to a reasonable length. Just my opinion.

Mossyoakglock · May 4, 2011

Both of my hoses are about 4'. I was trying to get a good balance of hose length vs distance from the engine to help keep the can cool. Currently mine is mounted to the bolt that holds the washer fluid tank to the core support. If I need to make the hoses shorter I would mount the can to the alternator bracket. The hoses would only be about 2' at that location.

I believe the hose length will have little bearing on the performance of the PVC system, if kept to a reasonable length. Just my opinion.

And now for a stupid question. I have the AMW can, what position does the drain screw need to be in to be closed? I have it fully extended right now.

kdixer · May 4, 2011

Quick question for you catch can guys. Do you do anything to the breather hose connecting the passenger side valve cover to the intake tube or just the one from the drivers side valve cover to the Manifold?

The breather hose on the passenger side is a fresh air hose. It replaces the air in the crankcase as it is purged by the PCV.

http://www.mightyautoparts.com/pdf/articles/tt122.pdf

Makes perfect sense. Thanks for the link.

cujo8 · May 4, 2011

Both of my hoses are about 4'. I was trying to get a good balance of hose length vs distance from the engine to help keep the can cool. Currently mine is mounted to the bolt that holds the washer fluid tank to the core support. If I need to make the hoses shorter I would mount the can to the alternator bracket. The hoses would only be about 2' at that location.

I believe the hose length will have little bearing on the performance of the PVC system, if kept to a reasonable length. Just my opinion.

And now for a stupid question. I have the AMW can, what position does the drain screw need to be in to be closed? I have it fully extended right now.

All the way extended out is the closed position.