Racetronix Oil Catch Can

[sltous]

Today I went for a nice blat and got to really exercise the catch can for the first time.

 

In a word, horrible. 

 

Not sure if the breather puked oil because it overflowed or because the stainless mesh somehow provided too much back pressure but I stopped to chat with a coworker and they pointed out an oil leak that was spilling down the side of the car and onto my muffler.  The ECU came out, the catch can came out, the heater blanking panels came out, floor mats came out, it was 30-40 mins of cleanup once I got home.  I'll be replacing the catch can with a larger unit immediately. 

 

I had topped off the car with ~60ml of oil this morning on top of 120ml from before changing my engine mounts.  Likely, when I was taking a quick drive between installing/torquing the engine mounts I did not work the system hard enough to overflow the main tank but all 60ml from this morning is currently decorating paper towels from blotting up the spill before I got home.  A system that just barely is big enough may be all well and good in theory but really a PITA in practice.

 

It may be possible to make the system work by swapping the locations of the breather and the input line but that requires spending $$$ on an 90 degree -10 ORB fitting that seems like throwing bad money after good at this point.

 

Edited April 9, 2022 by sltous
Adding photos

[Croc]

1 hour ago, sltous said:

In a word, horrible. 

 

I can relate.  Have done that once or twice a year to myself - it usually happens at each USA7s HPDE event where I look like a right wally covered in oil.  Its really a pain to get it out of the footwells as mine drips on to my legs there.

 

I suspect you already were at the right level and it all went to the catch tank.  Also it looked like it leaks first from the fabric breather as that is the first escape point.  So you really only have 2/3rds of a catch tank.   

 

Time for a bigger tank?

 

 

[sltous]

33 minutes ago, Croc said:

 

I can relate.  Have done that once or twice a year to myself - it usually happens at each USA7s HPDE event where I look like a right wally covered in oil.  Its really a pain to get it out of the footwells as mine drips on to my legs there.

 

I suspect you already were at the right level and it all went to the catch tank.  Also it looked like it leaks first from the fabric breather as that is the first escape point.  So you really only have 2/3rds of a catch tank.   

 

Time for a bigger tank?

 

 

For now I have re-fitted the Moroso breather tank as provided by the previous owner.  Neither of us is over the moon with the band clamp installation, and it is inconvenient that it is under the nose cone, but it has approx 1 quart capacity and doesn't puke oil so while I try and decide a new product this keeps me, the car, and and the roads clean.

Edited April 9, 2022 by sltous

[MV8]

So I tried researching this (selfishly for my own benefit/knowledge) and what I found was piece-meal at best and most of it from Croc. I still don't know what the low bell housing ports on each side go to or the design of the tower internals.  It seems to me the system check of spitting to the catch can is only for max oil volume and if that is needed, then the bell housing/tower tank is too small. If that is the case, a cooler, remote oversize oil filter or aux reservoir spliced in somewhere could add some capacity and allow a lower system level. FWIW, I'll share what I know. I am a master ASE and aircraft mech among other things if it matters.

A catch can can be service free with an open port to drain to the tank, a fitting, or any line with a normally open solenoid rated for gas/oil and a 12vdc coil. When running, the valve is powered closed and drains when shut off.

If you don't want to do all that, here is a tank with a sight glass with more capacity and ports for running the vent and drain valve. Mount with well nuts and run. This one has push-on hose barbs but they also have An10x2 and x4 if interested.

https://www.ebay.com/itm/393643262812?hash=item5ba6f7835c:g:0RMAAOSwKDZhcoMJ

The orientation of the catch filter is not important as long as the port is on top. If oil reaches the top, it will leak out of the filter anyway, so it might as well route down and away from anything you care about. It also does not have to be a racy filter. It could be a tube or hose with a screen over end or for less restriction, a couple inches of perforated tube on the end of a 3/8 tube that end near the lower frame rail with a remote drain routed next to it if not an automatic drain.

No need for AN fittings or orings. The pressure is very low.

Since we are talking about blow by, provent makes a great oil separator for turbo diesels and they are cheap. You can plumb the upper fitting into the tower catch port, the lower off the pressure valve into a filter, and the oil return into the dip stick hole (assume there is one that is plugged). Basically a very short dip stick tube with a hose slipped over.

https://www.mannfiltersrus.com/media/catalogues-pdf/MANN_HUMMEL_Crankcase_Ventilation_EN.pdf

https://www.ebay.com/itm/264532161728?_trkparms=amclksrc%3DITM%26aid%3D1110006%26algo%3DHOMESPLICE.SIM%26ao%3D1%26asc%3D238213%26meid%3D20401273eafb42a281f4187e4a6cf255%26pid%3D101195%26rk%3D3%26rkt%3D12%26sd%3D184954557133%26itm%3D264532161728%26pmt%3D1%26noa%3D0%26pg%3D2047675%26algv%3DSimplAMLv9PairwiseWebMskuAspectsV202110NoVariantSeedKnnRecallV1&_trksid=p2047675.c101195.m1851&amdata=cksum%3A26453216172820401273eafb42a281f4187e4a6cf255%7Cenc%3AAQAGAAABIF5w9SIYA7LCsjjN3P6Yl26VztH0VKUH9PSWDJnasZbD1yCZJUhd3q2YXl6I7nNELecZEIiewtb0d1ttsdLu1kMb6p%252BjWblBYHLAkZ5L6FWUhAI8Ck%252Bk%252FuDUkY8z3MEFZuYbOa5QdSk3GYrDpPR%252F3mHaoueQrBjAZJlEwVTeJ%252F12BTpjnndVhnxDsA%252B0N2Q2MfSyc668ECfrzpmRTFSfEwgt29XY6AV2NO0eUTh9%252FHqwW8YZ4UTsi8tj9G8VfCv3QnmBrMeWbnAjy4hsS%252F%252Bl8uBIm8Szp1d7LELCo9r7bvGv8Qv5geG%252BMyPrej12FBLWk8I0xpW%252BMQhvmz6lQotlIHqa8GP6Ue9k71odPAM%252BmW5QT3CjuemqprPxA6tbL3YG6w%253D%253D%7Campid%3APL_CLK%7Cclp%3A2047675&epid=8033953319

[Croc]

1 hour ago, MV8 said:

So I tried researching this (selfishly for my own benefit/knowledge) and what I found was piece-meal at best and most of it from Croc.

 

Yes it is a worry if you are relying on me! 

 

It is always good to get the thinking challenged - I have puzzled on this one for 12 years!  Before @sltous I was the only one with issues - probably because there are so few of these cars and I drive mine hard regularly.  I know other owners in the UK and only 2 have the issues that @sltous and I have.  They have been taking the same approach I have - larger catch tanks and careful application of oil.  

 

Could be worse - some of the early owners of these cars blew their engines from low oil.  Something we all wish to avoid.  

 

 

1 hour ago, MV8 said:

It seems to me the system check of spitting to the catch can is only for max oil volume and if that is needed, then the bell housing/tower tank is too small. 

 

Thats exactly the problem.  The compromise of placing the tank inside the bellhousing leads to capacity issues and also fries the clutch release seals over time from being surrounded by hot oil.  

 

The tank and tower is known for how it was designed and works - see here for a schematic of the tower

 

The bellhousing tank is below.  There is a blanking plate to seal it.  You can see the oil galleys that run forward to the Titan dry sump bolted to the engine.  The downloads section of the USA7s site has a schematic of the Titan Dry sump with its component parts.   You can just see the base of swirl tower on top of bellhousing.

 

 

 

 

Keep in mind, this tank is unable to be accurately measured for level as it is currently designed.  There is no way to test level through tower as oil is retained elsewhere in the system and does not always drain back to the bellhousing tank.  Putting a sight glass in a bellhousing is beyond my abilities.  Short of re-plumbing for a new oil tank outside of the bellhousing then a larger catch tank is the only (imperfect) solution. 

 

Solving at source, you would have a bigger oil tank unconstrained by the bellhousing.  Caterham did not use this design in any other car so I have to believe the experiences in the early CSR260s informed them this was a bad approach to persevere with.    My new CSR build is using a Pace tank which is 50% bigger by volume and can be measured by dipstick.  So the catch tank should no longer be a major concern in that design.   It will need a catch tank as these big Duratecs do have big crankcase pressures that cause them to breathe heavy.

 

1 hour ago, MV8 said:

If you don't want to do all that, here is a tank with a sight glass with more capacity and ports for running the vent and drain valve. Mount with well nuts and run. This one has push-on hose barbs but they also have An10x2 and x4 if interested.

 

https://www.ebay.com/itm/393643262812?hash=item5ba6f7835c:g:0RMAAOSwKDZhcoMJ

 

 

This is the same design as the larger capacity Mocal one which I know works well provided you are careful with your top ups.  Get it wrong and it will leak but thats human error.  I did not check but it looks to be the same one that fits for limited vertical height on the firewall shelf.  

 

1 hour ago, MV8 said:

Since we are talking about blow by, provent makes a great oil separator for turbo diesels and they are cheap. You can plumb the upper fitting into the tower catch port, the lower off the pressure valve into a filter, and the oil return into the dip stick hole (assume there is one that is plugged). Basically a very short dip stick tube with a hose slipped over.

 

https://www.mannfiltersrus.com/media/catalogues-pdf/MANN_HUMMEL_Crankcase_Ventilation_EN.pdf

 

 

 

Very interesting.  Have seen these on Landcruiser diesel offroad vehicles but never extended my thinking that this would be a solution for a Caterham CSR260.  Its a band aid to the original design issue but should work.  Not sure what I would tap the oil return into as there is no dipstick hole.  More thought needed on that.

 

  

 

 

[MV8]

I think a deep cup held by the inside vent fitting and drilling holes in the fitting tube would help to vent air versus oil. A screw on oil filter adapter to a remote filter base that accepts a common GM v8 filter could be used to add one or two quarts depending on the filter.

[MV8]

13/16-16, 3.25 pad fits chevys, ferraris, vipers (smaller base), etc. https://www.cantonracingproducts.com/content/Instructions/Engine Filter Thread Size.pdf

Edited April 10, 2022 by MV8

[sltous]

@MV8 I appreciate the advice.   For me, this car already holds approximately 6 liters of oil, I'd prefer to keep it close to topped up and I'd prefer not to puke any over-fill into the passenger footwell, but I think I personally can't justify an expansion tank for a dry sump tank for a race engine for a weekend driver street car.

[coffee break]

Does your catch tank need a catch tank?

 

I couldn't resist the smart a** question. Good luck y'all.

[MV8]

Funny, though it would work like a baffle. I'm thinking daisy chain. Yes, I kid, I kid, is joke.