caterhamnut Posted March 22, 2009 Share Posted March 22, 2009 Need one for our k-series. Can anyone recommend somewhere to buy one (unless 'Wanted' turns something up) Don't think I need a large capacity. I guess one pipe goes from the cam-cover breather, into the inlet on the tank. What goes on the 'outlet' plug found on most tanks - or is this just blanked off.... In fact - how do you fit and use an oil catch tank....? www.mycaterham.com here Videos here 102,000 miles car Link to comment Share on other sites More sharing options...
caterhamnut Posted March 22, 2009 Author Share Posted March 22, 2009 Ok - having now used the 'seach' facility I see that a good solution is a metal drinks bottle - I like the Dave J. solution of using a bike bottle cage to mount it - neat! So - just stuff the pipe into the top of one of these? www.mycaterham.com here Videos here 102,000 miles car Link to comment Share on other sites More sharing options...
6speedmanual Posted March 22, 2009 Share Posted March 22, 2009 The crankcase needs to breathe, so whatever container the breather pipe goes into needs to have an outlet too. This is normally acheived by an "out" pipe from near the top of the container which is directed down below the car. From this the crankcase fumes escape and any oil mist or drips fall into the catch tank. Another way is to have the catchtank outlet fitted with a small cleanable filter (eg K&N). This arrangement tends to discharge fumes directly into engine bay. Very smelly and noxious and can percolate through to cockpit. Using a metal drink bottle may work, but an outlet would have to be made or just have the breather pipe running loosely into the neck so fumes can escape. There are lots of proprietory tanks available for reasonable money on Ebay. HTH Peter 6SpeedManual *tongue*There's no such thing as too much BHP per Ton 😬 Link to comment Share on other sites More sharing options...
caterhamnut Posted March 23, 2009 Author Share Posted March 23, 2009 Thanks Peter - that makes perfect sense www.mycaterham.com here Videos here 102,000 miles car Link to comment Share on other sites More sharing options...
Fishy Dave Posted March 23, 2009 Share Posted March 23, 2009 Angus, I'm just changing my catch tank to a larger 2 litre one (needed for racing now), so my original smaller catch tank will be available to you if you'd like? Bit of payback for the pax ride you gave me all those years ago . It slots into a bracket which looks very similar to the type used for the washer bottle (available from cc), which is riveted to the chassis. Mine has a hole in the side where the pipe goes, with a blanking plate that can be used to have another pipe venting out of the engine bay. I have never had an issue with fumes (not from the engine bay anyway ). Blatmail me if you'd like it David Smitheram, Wiltshire (South) AR, 07718 368173. 1400 supersport ex racer Link to comment Share on other sites More sharing options...
caterhamnut Posted March 23, 2009 Author Share Posted March 23, 2009 Hi Dave - that sounds great. That location is where I was going to site anything I fitted, so could be perfect - I'll send you a Blatmail in a bit..... www.mycaterham.com here Videos here 102,000 miles car Link to comment Share on other sites More sharing options...
anthonym Posted March 23, 2009 Share Posted March 23, 2009 another revelation from 6speedmanual, thank you. "The crankcase needs to breathe". Now I understand why my oil catchtank has holes in it. and why a second catchtank for the catch tank is a good idea.. or might be. The first catches the excess and the second basically lets the pressure out. Problem with just the one, is that "the pressure" also takes oil with it - albeit presumably vapourised (breathing). Anthony - having one "aha" moment after another :-) Link to comment Share on other sites More sharing options...
Fishy Dave Posted March 24, 2009 Share Posted March 24, 2009 Hi Angus, I checked last night when home but couldn't see a blatmail? David Smitheram, Wiltshire (South) AR, 07718 368173. 1400 supersport ex racer Link to comment Share on other sites More sharing options...
MAK Posted March 24, 2009 Share Posted March 24, 2009 Angus Don't know what DS system you have but my Pace DS tank has two vent connections on top. My system works with the K series - engine breather connected to the top of the DS tank. The second DS vent is piped to a catch tank which presumably catches any oil overflow from the DS tank. This catch tank is then vented beneath the car, to avoid pressurising the system. In my case this Catch tank is approx 0.5 lt and so far no significant flow of oil has got to this tank. But I have only run the system for 200miles miles. Malcolm Link to comment Share on other sites More sharing options...
caterhamnut Posted March 25, 2009 Author Share Posted March 25, 2009 Malcom - I'm not actually running a DS system, but have TB's. Dave - sorry about that, will contact you now! www.mycaterham.com here Videos here 102,000 miles car Link to comment Share on other sites More sharing options...
MAK Posted March 26, 2009 Share Posted March 26, 2009 Angus I guess I missed that ,and got all excited about a string of catch tanks Malcolm Link to comment Share on other sites More sharing options...
Kevsta Posted March 26, 2009 Share Posted March 26, 2009 Malcom, I have a pace DS system, can I ask who said to set it up that way? The onlt reason I ask is that in general the Pace DS system has negative pressure in the engine and so breathers in the head will be sucking air rather than blowing (most of the time) so it will suck air from the catch tank (to my understanding). I guess this would suck oil mist into the engine, not sure if this is good/bad/not a problem? I have both of my breathers going to the same catch tank (no breather out of this at present, I moved it recently and so now don't get fumes to cockpit...a better solution would have been another pipe....but I ran out! Happy and open to comments on this.... Link to comment Share on other sites More sharing options...
MAK Posted March 26, 2009 Share Posted March 26, 2009 Kevsta This was discussed and agreed with Tony at Pace, because I wondered what to do with two vents from the top. It makes sense to me, bear in mind the oil level in the tank is just below the baffle which is only about half full. There is very little chance of any oil overflow going into the catch tank or cam cover. Agree that oil mist will go somewhere, but I don't see it being a problem if it goes into the cam cover. I think it is important not to run the engine sealed since I think i had read elswhere that presurising the engine can blow crankshaft seals. I also recognise this topic can be a little controversial. Malcolm Link to comment Share on other sites More sharing options...
BBL Posted March 26, 2009 Share Posted March 26, 2009 The October 2008 issue of Racecar Engineering magazine had an article about this very subject, and even had a Caterham Seven as their example in the photos. Their solution was to fit a one-way flapper valve in the hose from the valve cover vent to the catch tank so that the blow-by pressure can escape during higher rpm operation, but a vacuum can be maintained at start-up/idle and lower revs. I believe Minister Racing Engines was the consulting organization for the article. Sean Link to comment Share on other sites More sharing options...
John Howe Posted March 27, 2009 Share Posted March 27, 2009 Buy a windscreen bottle from Redline for pennies and you will find the opening it is a perfect fit for the appropriate size rubber hose they sell. Also, the bottle comes with its own bracket that can be pop-riveted to the pedal box! Do drill breather/vent holes in the top of the bottle, so that any excess air pressure can creep out. JH Deliveries by Saffron, the yellow 230bhp Sausage delivery machine Link to comment Share on other sites More sharing options...
Kevsta Posted March 27, 2009 Share Posted March 27, 2009 I'm little concerned now, I run mine pressurised (as was recommended when I fitted it). I haven't had any problems yet but am I letting myself in for one? Any chance of a scan of the article? Should I divert one to the cam cover breather (wouldn't be too much of an issue - want to do the right thing). Would the engine pressurise at high rpm or would the increase in spped of the pump not reduce the pressure further? Damn it Link to comment Share on other sites More sharing options...
BBL Posted March 27, 2009 Share Posted March 27, 2009 I had it wrong (no real surprise). The article reads, in part: "This (the flap valve) allows the build-up of pressure when a cold engine is being cranked to be vented off, yet stops it sucking air in through the breather when run at speed." While I am no expert, from what I have read, blanking it off won't cause any damage. Sean Link to comment Share on other sites More sharing options...
Kevsta Posted March 27, 2009 Share Posted March 27, 2009 So it is always sucking (which is what I thought it did but am always open to comments of change). So essentially any problems would arise from drawing in rather than blowing out. I think this was why I had to cap the breathers off from the inlet as it would have sucked fuel in otherwise. Think I'll leave alone (and possibly cry if it goes wrong...3 years in and it is ok though...) - touches anything resembling wood Link to comment Share on other sites More sharing options...
fergusd Posted March 27, 2009 Share Posted March 27, 2009 Just jumping across from another thread . . . my car has (always had) a caterham DS system fitted and it definately runs the crankcase under vacuum, all the breathers on the crank case are sealed and the only breather that is in place is a single one from the DS tank, this vents all the blowby at all engine revs . . . the engine was maintained and built by Minister, and the car was done about 8000 miles on track (only track use) . . . If the crank presure was ever positive it would blow off the crank vent caps which are simply pushed on to the ports, they have never moved but I can easily pull them off when the engine is stopped . . . Clearly the vacuum is an advantage power wise . . . and it doesn't seem to cause any other problems . . . $0.02 Fd Link to comment Share on other sites More sharing options...
Mick Day Posted March 28, 2009 Share Posted March 28, 2009 Just to throw a few more "spanners" in have a read of this: http://www.blatchat.com/t.asp?id=99079 Link to comment Share on other sites More sharing options...
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