BMS Stinger Zero Maintenance OCC Review

[Aarvix]

BMS Zero Maintenance Oil Catch Can

Keep oil out of your intake manifold! The BMS Zero Maintenance oil catch can keeps oil where it belongs preventing it from being sucked through the PCV system and coating your intake manifold, cylinder heat, and valves. In addition to the long term damage and maintenance headaches crankcase oil...

kdmwarehouse.com

I know there's some discussion in the JB4 thread about this OCC, but it'll easily get buried and I figured it's worth having its own discussion. I'll go first!

The unit itself is very nice, machining and anodizing are well done and the two halves fit together nicely with a small o-ring to keep it sealed. Inside, one half has a conical taper to facilitate the "drain back" into the crankcase (please pardon the terrible photo)



Inside, there are two baffles clocked half a hole from each other. The outlet is not 100% blocked from the inlet, some daylight can be seen through the baffles. Time will tell whether oil droplets will make it through or not.




My only critique of the unit is this:
The fasteners that hold the baffles in place were not installed with threadlocker. The PCV is upstream of the OCC, so if the screw were to work itself loose, the only thing keeping it out of the engine is the bend in the hose. I added some 242 loctite just to be safe.




Installation was super quick and simple, however there are no markings to indicate which end is the inlet/outlet. The online instructions cover this (plus it's pretty obvious if you unscrew the thing), but BMS might consider putting an arrow or "this side toward crankcase" nomenclature to further idiot-proof it.

The stock hose plus the OCC is a little long, but the taper of the OEM hose prevented me from trimming it. I may just replace the entire hose, but for now I made it work. I did have to remove the foam piece that was around the hose to keep it from kinking.



Overall I'm quite pleased with this piece. I'll open her up in a few hundred miles and report back.

 

[turboAWD]

Thank you! Can't wait for the next batch to be ready!

 

[Talloneus Khan]

To make up for not trimming the stock hose, I just trimmed the hose that came with it as much as possible

 

[WildBill]

Thanks for the review. I love the thought of a zero maintenance OCC but due to that aspect you never know just how effective it is.
Unless you look at the intake valves regularly I guess.

 

[Talloneus Khan]

I put alot highway miles on my car. @ 50k ill probably be looking, and will post here. Should be in about 10 months. So early spring 2020

 

[Terry@BMS]

To make up for not trimming the stock hose, I just trimmed the hose that came with it as much as possible

Yes the first batch we shipped them 3" so there would be extra room if needed, but the latest batch we're shipping at 2". You can cut that hose as short as you need.

 

[Terry@BMS]

Thanks for the review. I love the thought of a zero maintenance OCC but due to that aspect you never know just how effective it is.
Unless you look at the intake valves regularly I guess.

During development we placed a second OCC after it and it was quite a dramatic improvement. I think you guys will be happy with the results.

 

[JDM_Man]

During development we placed a second OCC after it and it was quite a dramatic improvement. I think you guys will be happy with the results.

How much efficiency is lost by it being a zero maintenance catch can vs a full set up?

Thanks.

 

[Kazz]

Waiting to hear results on this product! Thanks for posting this!

 

[oddball]

How much efficiency is lost by it being a zero maintenance catch can vs a full set up?

Efficiency depends on the separation method, not on how it drains.
The BMS can is no worse than most of the high dollar cans on the market. Efficiency of oil separation depends on the internal construction. Basic cans just have a separator plate with holes. The oil/air mist hits the plate and the oil condenses. The silly expensive ADD cans are this way, too. Most cans are, really.
It's better to have a real separator material, like the OEMs have in their systems. Some cans include a sintered bronze element which is a good start. Some include a wire mesh material like steel wool.

 

[Kazz]

Efficiency depends on the separation method, not on how it drains.
The BMS can is no worse than most of the high dollar cans on the market. Efficiency of oil separation depends on the internal construction. Basic cans just have a separator plate with holes. The oil/air mist hits the plate and the oil condenses. The silly expensive ADD cans are this way, too. Most cans are, really.
It's better to have a real separator material, like the OEMs have in their systems. Some cans include a sintered bronze element which is a good start. Some include a wire mesh material like steel wool.

So who's setup are you going/going to go with?

 

[oddball]

So who's setup are you going/going to go with?

Custom. $20 no-name can that has a separator plate and sintered bronze element. Added "filter material" (green scotch brite pad bits) and steel wool. Just have to make sure air still flows freely through the can - it can't be a restriction. Catches about 1 tbsp/500 miles. The fresh air side never caught anything. I removed that one because I didn't properly mount it so it was trying to destroy the TCM.... Eventually I'll bother to do it right, but that side isn't as critical.

 

[oddball]

Next time you're crawling through a junk yard, take a look at the OE valve covers on modern engines. They have oil/air separators built into the valve cover where the PCV pulls crankcrase vapors. Usually.

 

[Aarvix]

The conical "drain back" chamber of the BMS can is pretty large, I wonder if stuffing a little low density stainless steel wool in there would improve efficacy.

 

[WildBill]

Custom. $20 no-name can that has a separator plate and sintered bronze element. Added "filter material" (green scotch brite pad bits) and steel wool. Just have to make sure air still flows freely through the can - it can't be a restriction. Catches about 1 tbsp/500 miles. The fresh air side never caught anything. I removed that one because I didn't properly mount it so it was trying to destroy the TCM.... Eventually I'll bother to do it right, but that side isn't as critical.

So, you just chopping up the scotchbrite into bits? Would cutting disks and creating layers of scotchbrite / steel wool / scotchbrite have an advantage? Just as long as it didn't shut down the flow too much.
I'd think a stainless steel scrubby would be a pretty good material as well.

 

[Aarvix]

Remember that the PCV bypasses the air filter, so any crumbs that break off that scotch Brite pad go right into your engine.

 

[WildBill]

Most have a sintered brass filter (pneumatic muffler) that would filter the particulates. Many remove particulates down to 40 microns. You would want that for sure.

 

[Terry@BMS]

How much efficiency is lost by it being a zero maintenance catch can vs a full set up?

Thanks.

Difficult to quantify but it's not far off and is also less restrictive. Remember you always have to balance flow vs. separation. Add too much restriction and you open yourself up to a variety of side effects like blowing out engine seals.

The setup is designed so you can change the internal baffles too should we ever decide it's a good idea to make them less or more restrictive down the road.

 

[Terry@BMS]

The conical "drain back" chamber of the BMS can is pretty large, I wonder if stuffing a little low density stainless steel wool in there would improve efficacy.

It does but also adds restriction and the risk of particles draining back in to the engine so we played with it but didn't think the risks were worth the benefit.

 

[Metalmania82]

SO......to add material or not...