Oil catch tank - any recommendations?

Leeum

Leeum

Leeum

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19 Sep 2005
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I like the look of the Mocal catch tanks - handy too as they have a breathable cap but don't fancy shelling out £100 for one.

Can anyone recommend me something cheaper. There's a crazy amount of them on ebay but I've no idea what's good and what isn't.

Cheers
 
It's a catch can, you get whatever fits in your engine bay ;)

It doesn't do anything other than serve as a receptacle, you could use a milk carton if you wanted :p

Ones with the little air filters on them aren't great, they just stink instead and it can make your cabin smell, just stick a pipe on the other fitting and route it towards the road.

You only need two fittings, one in, one out, just merge them all into one pipe if you're using it for more than one breather if you don't want to waste money on an unnecessary fancy catch can with a fitting for every breather.
 
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I use a Roger Clark Motorsport one, complete with drain back to the sump made from armoured hydraulic line. Doesn't help the OP, but enables me to boast...:p


M
 
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sorted.
 
I'm tempted to go for one of these. There's quite a bit of oil comes out these days, it being an old motor.

I'm told cleaning out the rocker cover helps, but mine is made of plastic, so I can't soak it in solvents or anything like that. :(
 
Just thought I'd post anyway as not all the ones on ebay are the same - some come with baffles and all sorts of crazy things. I'll just buy whatever is cheap. :)

Main reason I want one is to stop the sensors in the throttle body getting gunked up with oil again - car runs like crap when they do. I've also heard that the oil vapour going back into the inlet reduces the octane rating of the fuel... not sure whether there's any truth in that but if it keeps my engine a bit cleaner, I'll be happy.
 
[TW]Fox;14977210 said:
Noob time.

What are these for? Suprised to see them being fitted to 'normal' cars?
Click to expand...

Normal cars just spit oil vapour back into the intake system AFAIK, mine does anyway :/
 
Leeum said:
I like the look of the Mocal catch tanks - handy too as they have a breathable cap but don't fancy shelling out £100 for one.

Can anyone recommend me something cheaper. There's a crazy amount of them on ebay but I've no idea what's good and what isn't.

Cheers
Click to expand...

Why do you want one with a breathable cap? Or is it soley to catch oil than attempt to control crankcase pressure?
 
[TW]Fox;14977210 said:
Noob time.

What are these for? Suprised to see them being fitted to 'normal' cars?
Click to expand...

Probably telling you what you already know to an extent, but:

Most engines have an oil system breather running from the rocker cover to the intake. To be sold in the EU, the breather must not vent to atmosphere.

Oil tends to come out too, and so there's usually a small quantity in the intake. For emissions this is good, but it hampers performance. Some people choose to use a catch bottle, to keep the intake free of oil and the vented gasses.

Older engines with more worn pistons/rings/bores, will end up with a higher crank case pressure, and so more oil gets into the intake, the air that comes out is also basically exhaust, which isn't so good either.

Did I miss anything?
 
My mate bought one for his Golf for £27.50 off eBay started out chrome and sprayed it jazz blue and it looks good. It has the breather filter, a lot less than what you were looking at. Might be a better solution if you don't like the idea of a drinks can :p
 
The cheaper ones tend not to have internal baffles. That said, some pan scourers can do the job of catching the vapour.
 
[TW]Fox;14977210 said:
Noob time.

What are these for? Suprised to see them being fitted to 'normal' cars?
Click to expand...

Most cars have the breathers venting to atmosphere. For competition you are not allowed to and in scrutineering they'll check that you are not venting to atmosphere and instead are catching it, as obviously they don't want oil on the track! Some people do just use a milk carton of something hehe.

The blue book should say IIRC what the minimum catch tank capacity is (dad's is in the study and I cba to check!).

E.G for the Westfield (2lt Zetec) there's one on the Cam cover and one on the crankcase. We've got both of these going to a 2lt catch tank, which has a sight tube, drain screw on the bottom and a breather on the top (otherwise the pressure would get too great and the hose pop off).

At OP, whether a Mocal one at £120 is any better than a Merlin's own and drill a hole for the breather at £85 is debatable!
 
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