So what makes an oil catch tank?
David Jenkins - 29/11/07 at 10:22 AM
When I fit my bike carbs I'll need an oil catch tank as there'll be nowhere in the manifold to take the fumes from the current system.
First of all, I don't intend to buy a bling stainless jobbie at vast expense, nor do I intend to fit an old coke tin (before anyone suggests!).
Being a practical sort of person I'll make most of the parts myself - but I'll need to know what's required.
Apart from the container, I'll need an inlet from the crankcase vent (which I'll also make), and maybe one from an oil-filler cap vent
(haven't got a cap with an outlet at the moment, but I may get one). Presumably these go into the side of the container near the top, and
probably bent down towards the base of the can?
Bought tanks seem to have a filter on the top - is this usual?
And do people fit a drain plug? Or do you just lift it up and pour it out? How much old oil am I likely to collect anyway, in a reasonably fit
crossflow?
cheers,
David
designer - 29/11/07 at 10:30 AM
Utilise an old windscreen wash reservoir.
Surrey Dave - 29/11/07 at 10:32 AM
I used a bike drinks bottle , plastic with mounting bracket very Locost.
Or you can splash out and get a lovely ally drink bottle with bracket for a few quid .
http://www.halfords.com/webapp/wcs/stores/servlet/categorydisplay_storeId_10001_catalogId_10151_categoryId_90916_langId_-1_topCategoryId__parentcatego
ryrn_31270_crumb_33980-31270_topcategory_31270
DarrenW - 29/11/07 at 10:34 AM
I had a tank made but its nothing special. Ive seen good results using an ali drinks bottle which can be bought for a couple of quid (Asda sell some
snazzy anodised ones). Try feeding the pipes in from the top and securing them so they dont touch the bottom of the can.
I recall someone making a tank from an old fire extinguisher before.
My tank doesnt have filter on top anymore and i dont feel the need to refit it. Mine just has an open top.
If you read any of my previous posts about catch tank design simply ignore most of them. Breathing issues were down to overfilling the sump due to
unknown origin dipstick.
Hopefully you will find it wont fill too quickly and a drain is not needed. I fed the tank from a crankcase outlet and another from oil filler cap
from top of rocker cover. Alternative method is to fit secondary outlet from rocker cover but take care on baffling it on the inside (and maintaining
cam clearance etc).
RazMan - 29/11/07 at 10:35 AM
They are a really simple affair, hence the Coke can idea.
In its simplest form it is just an inlet (top right), a chamber and an outlet (top) with a filter. The filter is just to stop particles getting
flushed through and is just a precaution.
Mine is a 99p drinks bottle and still looks good after 14k miles. I didn't bother with a drain valve but I havent emptied it yet as nothing seems
to collect in there - just a little water vapour which boils off once the engine reaches normal temps.
The inlet is just a hose pushed through a hole and runs down to 50mm from the bottom of the bottle. For the outlet I simply drilled a hole through the
bottle cap and put a little filter on the end of a short length of copper pipe.
[Edited on 29-11-07 by RazMan]
Rescued attachment Catch Tank.jpg
matt_claydon - 29/11/07 at 10:47 AM
Why is a filter ever used? Surely if the tank just gets emptied it doesn't matter if crap gets in?
RazMan - 29/11/07 at 10:51 AM
quote:
Originally posted by matt_claydon
Why is a filter ever used? Surely if the tank just gets emptied it doesn't matter if crap gets in?
The filter stops crap getting OUT 
martin1973 - 29/11/07 at 10:55 AM
just got an alli drink bottle of fleabay for one hole pound for mine.
DarrenW - 29/11/07 at 10:58 AM
quote:
Originally posted by matt_claydon
Why is a filter ever used? Surely if the tank just gets emptied it doesn't matter if crap gets in?
I dont understand this either. In my experience even when only vapours get caught be the tank it eventually gets crudded up and spits mess all over -
albeit not always a lot. If you recirculate the oil back to the sump them you will need one to stop crap getting in but a lot of engines dont breathe
enough oil to make that necessary.
Raz's pic is an excellent illustration of what can be achieved for little cost but still look great. Id start with this first but perhaps without
the filter so you can quickly keep an eye on its contents at first (also cheaper). If you find breathing is heavy and a lot of oil is expelled then as
i found it could suggest a seperate issue that will need to be resolved. Again as i found the issue may be simple to fix and not necessarily a sign of
something bad.
02GF74 - 29/11/07 at 11:10 AM
quote:
Originally posted by DarrenW
quote:
Originally posted by matt_claydon
Why is a filter ever used? Surely if the tank just gets emptied it doesn't matter if crap gets in?
it may depend on engine and howit is plumbed in.
rover v8 has breasther on the rear ofthe block that draws in air whcih then gets drawn via the breathers on the rocker covers.
so if a catch tank was plumebd in there, the filter stops much getting into the engine - but you probably would nnot fit the tank there so the mystery
continues.
maybe when the enigine is coling, air is drawn via the breather hoses so you deffo would wnat it to be filtered.
to stop stuff coming out - the oil fumes may get trapped/condense in the filter over time but as far as I can see on mine - xflow - it is clear and
althouh I have not emptied my tank, by shaking it it appears empty.
.... but back to your question.
if you want to make your own, I would suggest doiong ebay search ofr oil catch tank.
bascially you want hose ends at the top and onther one onto which you can fit the filter. more fancy version would have a right angled hose outlet
near bottom and another one at t he top between whcih you fit a transparent tube - this will show how full the tank is. more sophisticated wold be to
fit a drain - i have one on my kit kat can, a domestic radiator drain from B&Q.
how much time and money you want to spend is up to you but you are not going to get massive increases in performance over a beer can and tube.
BenB - 29/11/07 at 11:52 AM
If your Crossflow emits as much oil as everyother Xflow I've met one this big should do the trick
David Jenkins - 29/11/07 at 12:25 PM
No, only a decent drip tray is required...
Rescued attachment 10000FS.jpg
Danozeman - 29/11/07 at 12:51 PM
MIne is like razmans. Or it will be when iv fitted it.
Poundland a quid or i think wilkinsons do them for 99p if u want locost
2b_pablo - 29/11/07 at 01:29 PM
nutriprem baby milk carton 
David Jenkins - 29/11/07 at 01:50 PM
Not quite the image I'm trying to make, unfortunately! (and no babies in this household since a long time ago!)
Looks like a trip to Halfrauds on Saturday...
Ta.
jacko - 29/11/07 at 04:43 PM
I used a old wd40 can then went bling bling and used a old spray gun can made off alloy it has a nice big top that locks on and fit a filter on
the top were the pickup pipe would be
David Jenkins - 29/11/07 at 08:11 PM
As a matter of interest - is there a right place to mount one of these things? I was going to put it on the engine side of the scuttle, purely
because there's some space there.
I'd guess that if it's too low then anything that gets into the pipe is going to drip down into the tank. At least if it's high then a
fair bit is going to flow back into the engine...
Not that my engine is going to blow any oil around, you understand!
thomas4age - 30/11/07 at 09:23 AM
hmmm
what about mine then?
I'd rather have the original content but hey hadn't seen one before so....
oil catchtank heineken
grtz Thomas
2b_pablo - 30/11/07 at 09:45 AM
where does the bottom pipe go? back to the sump?
RazMan - 30/11/07 at 09:47 AM
quote:
Originally posted by thomas4age
what about mine then?
Just a thought ... Does that design actually catch any oil? I would have thought the oil vapour would just shoot out of the filter without having any
time to condense in the bottle.
