How Do You Properly Run An Oil Catch Can?

[Ownallday]

I have a 280z with an L28 and triple webers, I recently went to the track and my car caught on fire, it looked like the fire was coming from my headers or from the middle weber and the fire started about 3 minutes after I spun out and was idling for about 2 minutes in the pits. For now I want to assume the fire started due to oil dripping onto my headers after spinning out and the fire probably seeped through the middle weber and ignited there too. (The car is okay I drove it home two hours away with no problem just 2 hours after, nothing looks damaged and the car drove like nothing happened)

 

I have a K&N breather for both the valve cover and the crank case portion on the block (PCV). I would like to add that during the fire the K&N breather on the block blew off (exploded off). Gonna assume it got clogged and pressure wasn't able to be released or something of that nature.

 

I want to ditch these breathers and run an Oil Catch Can system asap before my next track day as it seems for normal street driving I don't have to worry much. I would like to know the best way to run it.

I've seen 4 setups:

1: Running one catch can with two ports (one port is an inlet and other is an outlet with a filter on top) and the valve cover and crank case both have hoses going to the two ports separately.

2: Running one catch can with two ports (one port is an inlet and other is an outlet) and both the valve cover and crank case hoses connect to a T or Y fitting and then run to the inlet on the catch can with a filter on the outlet portion of the catch can.

3: Running one catch can with one port and a filter on top and both the crank case and valve cover have hoses that connect to a T or Y fitting and run into the one port in the catch can

4: Running two separate catch cans with filters on top, one catch can for the valve cover and the other catch can for the crank case

 

I would also like to add that I do have a small amount of blow by and does fume up the cabin slightly so whichever system would be best to help reduce this would be appreciated or whichever system is the best overall to run.

[AK260]

Sorry to hear that! Must have been very scary!!! Glad the car is fine.

I hate those filter type things as they invariably get “wet”.

Here’s a photo of my set up (except I now run an airbox). If you look bottom left you will see my catch can. It’s a 0.3l cheap eBay one with two inputs and one output. The best catch cans (unlike mine) are baffled.

The top of that filter can sometimes smell eggy - you can always route a pipe away from the top to somewhere in the engine bay where it doesn’t matter.



Also note the home made heat shield that works amazingly in keeping the carbs cool and diverting any fuel leakage / spit back away from the hottest part of the exhaust manifold.

[grannyknot]

I run this baffled catch can, https://www.ecstuning.com/b-ecs-parts/ecs-tuning-baffled-oil-catch-can-8oz/003779ecs05-02~a/

It is configured as your #1 setup, works great.

@AK260, beautiful engine bay!

[dutchzcarguy]

What strikes me in that pic @AK260 is that the cable with nr:5 on the distributor is on the wrong spot? (1 is on front normally and then 5-3-6-2-4... ?) 

Your distributor axle is not installed properly or that number is on the wrong cable..  oh yeah i sayd it already.. i'm a "muggezifter.. hahaha..)  Sorry Ali !!! 🙂 

NICE clean engine compartment though! 👍

Edited July 27, 2021 by dutchzcarguy

[AK260]

4 hours ago, grannyknot said:

I run this baffled catch can, https://www.ecstuning.com/b-ecs-parts/ecs-tuning-baffled-oil-catch-can-8oz/003779ecs05-02~a/

It is configured as your #1 setup, works great.

@AK260, beautiful engine bay!

Thank you sir - the wiring has been cleaned up further since then 😛. That's a great catch tank!

 

3 hours ago, dutchzcarguy said:

What strikes me in that pic @AK260 is that the cable with nr:5 on the distributor is on the wrong spot? (1 is on front normally and then 5-3-6-2-4... ?) 

Your distributor axle is not installed properly or that number is on the wrong cable..  oh yeah i sayd it already.. i'm a "muggezifter.. hahaha..)  Sorry Ali !!! 🙂 

NICE clean engine compartment though! 👍

Well Mr. Dutchie Hawkeye, you're spot on with that cable being in the wrong place under normal circumstances. BUT, the dizzy shaft is perfect. The 123 Ignition has a slightly strange config and you may not have seen on one of my recent posts where I mentioned this strange thing and how I blew up my muffler by having the timing something like 270-280 degrees out - by not looking at the rotor and wiring up the cap as you imagine it should be! On the 280zx dizzy the rotor would point to the rad panel at TDC. 123's points to the fender, hence what you're seeing. 

Edited July 27, 2021 by AK260

[Ownallday]

7 hours ago, AK260 said:

Sorry to hear that! Must have been very scary!!! Glad the car is fine.

I hate those filter type things as they invariably get “wet”.

Here’s a photo of my set up (except I now run an airbox). If you look bottom left you will see my catch can. It’s a 0.3l cheap eBay one with two inputs and one output. The best catch cans (unlike mine) are baffled.

The top of that filter can sometimes smell eggy - you can always route a pipe away from the top to somewhere in the engine bay where it doesn’t matter.



Also note the home made heat shield that works amazingly in keeping the carbs cool and diverting any fuel leakage / spit back away from the hottest part of the exhaust manifold.

Wow that is one amazing engine bay!

Yeah I was really scared especially when I opened my hood and the fire engulfed up, I am shocked to see no damage though, looks like nothing was burnt either.

3 Ports? How to do you have it setup? To my knowledge the crankcase hose should connect to the input and the valve cover hose connects to the output? Do you have the 2 input blocked off?

I am actually in the works of making my own heatshield for the webers to hopefully help keep fuel leaks off if I have any.

 

5 hours ago, grannyknot said:

I run this baffled catch can, https://www.ecstuning.com/b-ecs-parts/ecs-tuning-baffled-oil-catch-can-8oz/003779ecs05-02~a/

It is configured as your #1 setup, works great.

@AK260, beautiful engine bay!

Thanks for the response, I believe this is how most people are running it too. Are you connecting the crankcase to the input or the output?

[AK260]

2 hours ago, Ownallday said:

Wow that is one amazing engine bay!

Yeah I was really scared especially when I opened my hood and the fire engulfed up, I am shocked to see no damage though, looks like nothing was burnt either.

3 Ports? How to do you have it setup? To my knowledge the crankcase hose should connect to the input and the valve cover hose connects to the output? Do you have the 2 input blocked off?

I am actually in the works of making my own heatshield for the webers to hopefully help keep fuel leaks off if I have any.

 

Thanks for the response, I believe this is how most people are running it too. Are you connecting the crankcase to the input or the output?

Thank you sir.

 

The catch tank has two inputs (one from the crank case and one from the valve cover). The output is on top where the filter is. But unlike adding a filter to the actual engine block breather, the oil / vapour particles hit the tubing and the tank first before trying to come out of the vertical exit (i.e. the filter) so it doesn't create a mist under the bonnet.

 

Have a look at this - its pretty close to what I have.

https://www.ebay.co.uk/itm/173727362404

Edited July 27, 2021 by AK260

[AK260]

Ps. In fact, this is pretty identical to what I have - https://www.ebay.co.uk/itm/182121157542?hash=item2a674453a6:g:WnEAAOSw3mpXLGeB

 

I like the sight tube as I can tell how full it is.  Normally it gets a 1/3 full after say 2-3K miles of fast roading.

[grannyknot]

5 hours ago, Ownallday said:

Thanks for the response, I believe this is how most people are running it too. Are you connecting the crankcase to the input or the output?

I don't think it really matters but I would assume there would be more oil mist coming from the crankcase, you won't believe the stuff that accumulates in the can, in racing circles it's known as a snot can for a good reason.

[Ownallday]

6 hours ago, AK260 said:

Thank you sir.

 

The catch tank has two inputs (one from the crank case and one from the valve cover). The output is on top where the filter is. But unlike adding a filter to the actual engine block breather, the oil / vapour particles hit the tubing and the tank first before trying to come out of the vertical exit (i.e. the filter) so it doesn't create a mist under the bonnet.

 

Have a look at this - its pretty close to what I have.

https://www.ebay.co.uk/itm/173727362404

Ok, thanks, I will be setting up similar to yours then, I went ahead and ordered another catch can to hopefully match my engine bay nicely. Thank you for all your input.

3 hours ago, grannyknot said:

I don't think it really matters but I would assume there would be more oil mist coming from the crankcase, you won't believe the stuff that accumulates in the can, in racing circles it's known as a snot can for a good reason.

When I had the breathers on you can actually see more blow by coming from the valve cover breather which I thought was odd. Hopefully the addition of a catch can helps reduce the amount of blow by though and fumes and overall no more burning engine bays!

[dutchzcarguy]

19 hours ago, AK260 said:

Well Mr. Dutchie Hawkeye,

Just had to say that was very funny..! 👀

[AK260]

@ownallday - you’re most welcome. Keep this thread up to date so that we can see how you got on.

On my brother in law’s TR6, being push rod, the cam cover breather is like a steam train chuffing away and it made me cough when I had it unplugged. Now if a car ever benefits from a catch tank it’s that one!!!!

I’m surprised you’re getting large blow-by from the top of the engine. I’ve found on mine the engine block breather is normally the one with more output. And I have pretty good rings with 205psi dynamic compression.

One tip, I used 15mm copper pipe inside the I think it was 16 or 17mm hose from the cam cover breather to make sure it stays in the shape I want and doesn’t crush around the bends when it heats up. It was a female dog to get in even with silicone lubricant so you can always try 10mm copper pipe. The key thing is to ensure it doesn’t crush on the bends or change shape and foul itself against other engine bay parts.

Another trick (if you’re not bothered about the exact shape / routing of the pipe) which I have used to GREAT effect on the fuel tank breather that does the crazy 180° turn is to place a 15mm pipe bender spring permanently in situ inside the 16mm hose - it will never crush!!



15mm Internal Pipe Bending Spring https://www.amazon.co.uk/dp/B00NW4NJAY/ref=cm_sw_r_cp_api_glt_fabc_V3G163TST9N5H9N8MJEQ?_encoding=UTF8&psc=1



@Dutchyhawkeye - glad to be of service sir! [emoji12]