jonost24 Posted September 20, 2010 Share Posted September 20, 2010 Anyway Nige, I'd fit a shiny catch tank and drain the oil every now and again. Quote Link to comment Share on other sites More sharing options...
Hybrid_From_Hell Posted September 20, 2010 Author Share Posted September 20, 2010 up Dragging this back from its current direction of a bit of willy waving competition I thought I would post pics of it now cleaned (its currently "Drowing" in Cleaner), but Unsure where the 2 pipes go. I guess the top is bretaher, bottom is a bung, but a to where the 2 pipes connect I am stumped at the moment Pics : Thoughts as to plumbing ? If not hopefully as it goes together I might twig ?? Nige Quote Link to comment Share on other sites More sharing options...
Boothy Posted September 20, 2010 Share Posted September 20, 2010 Nige "old chap" A lot of high end racing engines use the "catch tank" collections for analitical reasons i.e. check how's the engine running, and to look for any impending disasters by analising the contents, I saw this today on a Sky Discovery breakfast filler programme where some bod was building a kit car for racing (no not Mark Evans, some other lunatic with a Hyabusa??? engine, 1300cc and 160BHP WOW) it demostrated the use of the oil catch tank for this use, especially when the engine is at racing stresses, not that your 12 gallon fuel tank will be large enough to get a 5.2 Eales stressed, more than likely SWMBO will be wondering where all the extra fuel money is going and will be getting morestressed than your crankcase Pal. Oh well, back to plucking Phesants. Quote Link to comment Share on other sites More sharing options...
Range Rover Blues Posted September 20, 2010 Share Posted September 20, 2010 Noy my Dr Degree, my lecturer. At the time senior lecturer at Brunel Univeristy where I got my degree in Mechanical Engineering and Automotive Design. Sorry about the confusion but I'm used to quoting references because I work in education. Effective CR, well that's what I know as volumetric efficiency. On a Turbo engine this can exceed 100% of course. I guess you say tomato...... Got to go for now.... Quote Link to comment Share on other sites More sharing options...
V8 Freak Posted September 20, 2010 Share Posted September 20, 2010 Nige, Wonder if this pic helps.... Additional breather ? Maybe the original didn't have a breather take off on the back of the rocker cover like you have on the 4.5 and it pulled air from the top of the tank ? Probably helps to condense the oil too ! Neil Quote Link to comment Share on other sites More sharing options...
Range Rover Blues Posted September 20, 2010 Share Posted September 20, 2010 I've had one of those, it didn't actually spearate much oil though. Quote Link to comment Share on other sites More sharing options...
Lara Posted September 21, 2010 Share Posted September 21, 2010 Yes I agree with that one! It looks far too small. It is actually one hell of a job to make a good shaped catch tank that does not blow oil out the top under race conditions when your engine is "breathing hard" Nige Top pipe is breather to filter box or for a separate filter etc, Side pipes are inlet from engine, either both rocker covers or crank case inlet valley and rocker cover, but would suggest both rocker boxes! Also if you rivet a small plate over the inside of the fittings in the rocker cover, these will act as "splash deflectors" and stop the rocker gear throwing oil into the pipes! Your tank hopefully has extensions to the "IN" pipes on the side that turn 90 degrees and point them down. If not then cut a saw slot across the width of your tank, vertically down and at 90 degrees to the inlet pipes, from the single "OUT" pipe fairly close to it and on the side of the inlets and going down to about 10mm past the bottom of the lower of the two pipes. Then insert a piece of ally sheet cut to size and weld shut again. This will act as a reasonable baffle / deflector for the oil particles suspended in the "breathing" air. (I am trying to describe a plate shielding the inlets and outlet) How is the build going? We are all excited! And out of interest, how much is it costing? I remember years ago building a few 4.6 litre engines for F2 Ski boat racing, and parts made it rather expensive. I would be very interested to know if things had changed? Everyone always quotes the negatives of your type of build as too expensive compared to yanks etc but is that still true? Regards, Lara Quote Link to comment Share on other sites More sharing options...
Bush65 Posted September 21, 2010 Share Posted September 21, 2010 Noy my Dr Degree, my lecturer. At the time senior lecturer at Brunel Univeristy where I got my degree in Mechanical Engineering and Automotive Design. Sorry about the confusion but I'm used to quoting references because I work in education. Effective CR, well that's what I know as volumetric efficiency. On a Turbo engine this can exceed 100% of course. I guess you say tomato...... Got to go for now.... Effective CR is not the same as volumetric efficiency. However VE accounts for the difference between effective and static CR. Quote Link to comment Share on other sites More sharing options...
rusty_wingnut Posted September 21, 2010 Share Posted September 21, 2010 The top outlet is to vent to atmopshere or somewhere like the breathing system on the engine. You should have an inlet, and an outlet, inside there may be a baffle to turn the gasses and almost stall the flow allowing andything denser than air to drop into the bottom of the tank and the air to travel out of the top end outlet. The bottom drain can be connected to the nonpressured side of the sump with a one way valve if required - though I would not reccomend that in this case. Quote Link to comment Share on other sites More sharing options...
Aragorn Posted September 21, 2010 Share Posted September 21, 2010 Probably also an idea to run the top outlet to your snorkel or back to the inlet manifold, because if you sumberge that tank you risk filling the motor with water. Quote Link to comment Share on other sites More sharing options...
V8 Freak Posted September 21, 2010 Share Posted September 21, 2010 Lara, Are you advising that the catch tank is just naturally venting and there is no need to pull vapour through the vacuum system and back into the plenum? Neil Quote Link to comment Share on other sites More sharing options...
BogMonster Posted September 21, 2010 Share Posted September 21, 2010 Noy my Dr Degree, my lecturer. At the time senior lecturer at Brunel Univeristy Was that where you learned to spell? Quote Link to comment Share on other sites More sharing options...
Lara Posted September 22, 2010 Share Posted September 22, 2010 Lara, Are you advising that the catch tank is just naturally venting and there is no need to pull vapour through the vacuum system and back into the plenum? Neil Hi Neil, No not recommending it in this instance. I would agree with Aragorn about the water issue! However on a race engine you rarely plumb it back to the inlet as oil can contaminate the inlet charge and cause detonation, because generally if building a race engine to it's best potential you would be running the highest RC possible to get away with given your rules and regs and fuel available etc. It would be unwise to let oil get in there! Actually, the clever racing guys sometimes plumb it into the exhaust in a way to use the exhaust to create a negative pressure and suck from the tank! Not so easy in reality though and you need a very free flowing exhaust system for this! Lara Quote Link to comment Share on other sites More sharing options...
V8 Freak Posted September 22, 2010 Share Posted September 22, 2010 I understand the water issue (Especially knowing how Nige uses his truck...) and the desire to not feed oil back into the combustion process. I was wondering if Nige / others should consider a high level inlet (probably at the top of the snorkel, but not in the snorkel) that feeds fesh air into the engine and the breather from the oil tank in the snorkel so that the relatively low pressure in the snorkel draws some air through the engine and helps it breathe / remove the oil saturated high temperature vapours for the oil tank to catch ? Neil Quote Link to comment Share on other sites More sharing options...
Aragorn Posted September 22, 2010 Share Posted September 22, 2010 Where exactly would you be planning to connect this "fresh air" inlet? Quote Link to comment Share on other sites More sharing options...
Hybrid_From_Hell Posted September 22, 2010 Author Share Posted September 22, 2010 somewhere waterproof Nige Quote Link to comment Share on other sites More sharing options...
Lara Posted September 22, 2010 Share Posted September 22, 2010 Into the cab heater, so on hot days you can smell how good your engine is breathing Lara Quote Link to comment Share on other sites More sharing options...
Aragorn Posted September 22, 2010 Share Posted September 22, 2010 What i implied, was that the engine breather system does not "suck in" fresh air. It expels crankcase blowby, and in this case, imo, it should be expelling it into the inlet. V8 Freaks post suggests there would be two pipes, one emptying these fumes from the catch tank into the inlet, and one providing fresh air from somewhere high up... My post was asking him where this fresh air feed was supposed to connect to on the engine. Quote Link to comment Share on other sites More sharing options...
V8 Freak Posted September 22, 2010 Share Posted September 22, 2010 Where exactly would you be planning to connect this "fresh air" inlet? Don't know exactly as it's Nige's engine / not my engine and partly a hypothetical question to understand the ideal fittling of an oil tank like this for future reference and to see if we could offer good advice up front for others to read and learn from.... I do believe that this type of thread can be a great source of information for others and not have to get into the milimeter perfect location of a breather on an engine...... Neil Quote Link to comment Share on other sites More sharing options...
zim Posted September 25, 2010 Share Posted September 25, 2010 The problem with doing it as suggested above (both rockers into the catch tank, then a natural vent to atmosphere from the top) is that gasses do not circulate around the engine. If you have a search around v8forum.co.uk you'll see they advise to keep a flow going round.... that's why on the standard efi v8 there is a mushroom on the top of one of the rocker covers and the other rocker goes back into the suction in the plenum / inlet. on the carb'd models there is a pipe from each rocker back into the plenum but then they also had a breather at the back of the engine in the valley. I've heard of people running small vacume pumps on catch tanks to get it to circulate and then having an "inlet" somewhere on the engine. It was also suggested above that you put "splash" guards below the ports on your rocker covers. If you use the older style rocker covers (carb'd ones, stage 1's etc), it's easy to get a pipe on and those engines came with little splash plates that bolt onto the rocker bolts for this very purpose. Again, it depends on if your rockers allow this if they're different ???? (I may have a spare pair knocking about). Don't forget to put flame traps in line HTH G Quote Link to comment Share on other sites More sharing options...
Hybrid_From_Hell Posted September 26, 2010 Author Share Posted September 26, 2010 Hmmmm Ok found the Rocker covers in Box No 4 Odd Passenger side = Filler at front and a approx Aeroquip 1/2 BSP / JIC Fitting nicely coverted to the rear Drivers side, Flame trap unit has a JED Bung Plate in itm, and the rer - well thats been "Got at" by Previous owner - sheared off Aeroquip unit with what looks like a heater pipe sawn off and araldited shall we say in a "Bodgeattastic" way So, I have 2 vents from the rockers - each sidee going to the 2 x pipes on the ctach tank, can't see either way around will make any difference ? (thats a Q Bu the way ?) there is a baffle plate between to 2 side inlet, with a drain hole between them JED has made "Sheilds" over the outlets, but no flame traps I can see, other than a large amount of Stainless wire wool in the big vent at the top of the tank ? Bung / drain in the base, the tube Sir Eyeore of Kam has advised me is a "How full guage" tho it could do with a hose change, and the top 1" outet is a vent to air, which I'll ned to plumb somewhere "Dive Dive Dive" Safe Seems just about everything the previous owner to whom I bought it from b*ggered up just about everything he touched Ho Hum Nige Quote Link to comment Share on other sites More sharing options...
V8 Freak Posted September 26, 2010 Share Posted September 26, 2010 So what Zim has shown us is that you ought to have a go at getting flow in the system, but JE built it to waft about a bit and catch oil... So what's right ? Neil Quote Link to comment Share on other sites More sharing options...
Hybrid_From_Hell Posted September 26, 2010 Author Share Posted September 26, 2010 And thats al I have to say on the matter ? Nige Quote Link to comment Share on other sites More sharing options...
V8 Freak Posted September 26, 2010 Share Posted September 26, 2010 Profound coming from you Nige.... Neil Quote Link to comment Share on other sites More sharing options...
zoltan Posted September 27, 2010 Share Posted September 27, 2010 If you want to do something useful with that bung on the bottom of the catch tank if you have an engine that chucks half of its oil up into the catch tank each event (more for high revving engines on circuits) pipe it back to the sump but it is essential to get the pipe in under the oil level in the sump otherwise the crank pressure will impede the drain back. Under the oil level there is no positive pressure. The catch tank then still does its job of oil separation but doesn't end up like an oil reservoir Quote Link to comment Share on other sites More sharing options...
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