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Crankcase ventilation on a Zetec - help needed
Rena - 19/1/15 at 12:50 PM

Hi,

I´m trying to set up my Zetec with twin Weber 45 but I have some issues with my setup.

My current setup is like the picture

Crankcase

I´m also running a small pipe from the rocker cover to the filter base plate.

Is this correct?


loggyboy - 19/1/15 at 12:55 PM

Pic fail... lol
corrected


Paul Turner - 19/1/15 at 01:04 PM

On my Zetecs (carb and injection) the crank vents to a small plastic bottle and the cam cover vents into the same bottle.

No need to connect to carbs etc.

Very little collects in the bottle thus it vents to atmosphere.

[Edited on 19/1/15 by Paul Turner]


Rena - 19/1/15 at 01:06 PM

quote:
Originally posted by Paul Turner
On my Zetecs (carb and injection) the crank vents to a small plastic bottle and the cam cover vents into the same bottle.

No need to connect to carbs etc.


Thanks - so no connection to the inlet manifold?


Paul Turner - 19/1/15 at 01:31 PM

Bottle is top left.

Small 3rd pipe is from gearbox.

No connection to inlet.



19sac65 - 19/1/15 at 02:09 PM

Zetecs dont breath very heavy,like older engines
As said above,very little collects
I blocked off the crank breather with a core plug ( off ebay) and vented from the rocker into a catch tank- then out via a little filter
Works fine


big_wasa - 19/1/15 at 03:08 PM

The manifold connection will be for a brake servo so not needed.


jeffw - 19/1/15 at 03:27 PM

quote:
Originally posted by 19sac65
Zetecs dont breath very heavy,like older engines
As said above,very little collects
I blocked off the crank breather with a core plug ( off ebay) and vented from the rocker into a catch tank- then out via a little filter
Works fine


actually it doesn't. You need both camcover and crankcase breathers, especially if you are using forced induction.


19sac65 - 19/1/15 at 03:33 PM

Its works fine for me - its a popular mod within retro ford owners
Various plates and plugs available so there must be a market for them
But then i suppose we have have different ways of doung things


[Edited on 19/1/15 by 19sac65]


jeffw - 19/1/15 at 03:42 PM

Yeah....obviously Ford wasted their time doing a crankcase breather...


Paul Turner - 19/1/15 at 03:51 PM

quote:
Originally posted by jeffw
Yeah....obviously Ford wasted their time doing a crankcase breather...


Exactly what I was thinking. Ford, like all manufacturers, always fit more parts than are actually needed for the engine to work correctly.

But like in all forums some posters know better than a manufacturer who builds loads of these engines.


davidimurray - 19/1/15 at 04:09 PM

Think about this - for pressure to escape from the crankcase, if the crank oil breather is blocked, then it will have to travel up to the head vent, the only route is through the oil drains so you will have air flowing upwards against the oil drain flow.

I also notice that on the Duratec the crank breather is described as an oil seperator and has a horizontal lip to collect the oil before the outlet.


jeffw - 19/1/15 at 04:18 PM

What happens is that the crankcase is pressurised and then blows the dipstick out (followed by oil all over the exhaust manifold)....ask me how I know this!


19sac65 - 19/1/15 at 05:50 PM

quote:
Originally posted by Paul Turner
quote:
Originally posted by jeffw
Yeah....obviously Ford wasted their time doing a crankcase breather...


Exactly what I was thinking. Ford, like all manufacturers, always fit more parts than are actually needed for the engine to work correctly.

But like in all forums some posters know better than a manufacturer who builds loads of these engines.



Ladies
Is the idea of a forum to give your opinion,or agree with everything others say ( and comment on)
I accept that you are confident of your opinion by your follow up post - ridiculing mine
I assume that your engines are just as ford built them as they only run properly that way
I wasnt aware that ford fitted carbs to zetecs,and thought ( obviously wrongly) that the crank breather was also to allow crank gasses to be recirculated through the inlet to reburn,thus keeping the emissions down - something that wont concern someone whos fitting twin webers

My dipstick has never blown out,my catch tank doesnt chuff oil everywhere and ive no oil leaks
I can only conclude my engines in better nick than yours

[Edited on 19/1/15 by 19sac65]


whitestu - 19/1/15 at 08:30 PM

Mine vents from the crank and cam cover into the air filter backplate.

No idea what comes out when driving hard but I've never had any problems.

Stu


Andybarbet - 19/1/15 at 08:44 PM

Here's what I've done, I hope it's ok ? I made the block breather from an offcut of thick Ali I had laying around, just need to cut a gasket for it, then i opened up the cam cover pipe with an 11mm drill (I think) & tapped 1/4" bsp for the brass fittings found in my compressor/airline fittings drawer in the garage, these will both connect into a breather tank with a small filter on top.

zetec block breather outlet
zetec block breather outlet

zetec block breather
zetec block breather

Cam cover breather
Cam cover breather


Feel free to let me know if this won't work ? I would rather plumb this lot in, just in case, rather than not bothering & finding out later that i should have.


johnemms - 20/1/15 at 12:01 AM

catch can
catch can

pipe from crankcase comes up to a T piece .. (low so as to drain back)
One pipe into bottle.
Outlet - blue tube to atmosphere ground.

Feel free to put a filter on output.. when it gets soaked with vapour it causes back pressure. Even worse if oil contaminated.


jeffw - 20/1/15 at 06:24 AM

Get the standard blacktop crankcase breather and fit it. Connect the crankcase breath and camcover breather into a can/bottle/expensive aluminium catch can but don't T the lines together.


Paul Turner - 20/1/15 at 09:20 AM

quote:
Originally posted by 19sac65I wasnt aware that ford fitted carbs to zetecs,and thought ( obviously wrongly) that the crank breather was also to allow crank gasses to be recirculated through the inlet to reburn,thus keeping the emissions down - something that wont concern someone whos fitting twin webers

My dipstick has never blown out,my catch tank doesnt chuff oil everywhere and ive no oil leaks
I can only conclude my engines in better nick than yours

[Edited on 19/1/15 by 19sac65]


Ford never fitted carbs to Zetecs. Its people like us who use Zetec in older vehicles and Kit cars who fit carbs (and aftermarket TB injection).

In a production engine fitted with all the relevant emission kit the crank case vapours are routed back into the air box via various valves etc but in Kits cars that do not have to meet those regs there are simpler ways to do it i.e. strait to a bottle.

But carbs or injection, the block and head still need to breath.

My original Zetec was a bog standard £150 buy from a car that had suffered a dash fire. I had no idea of the mileage. Fitted a new timing belt, water pump and once fitted with twin 45's started first touch of the key, never burned any oil and there was only ever a tiny trace of oil in the catch tank (unlike my earlier x-flows). Still have the engine as a spare.

My second Zetec was a bored out 2.1 with stage 2 head and Kent FZ 2002 cams. Again, there was only ever a tiny trace of oil in the tank.

My current Zetec was a brand new crate Blacktop. Exactly the same as the others.

Don't think yours can be in better nick than mine.

[Edited on 20/1/15 by Paul Turner]


Rena - 17/2/15 at 12:11 PM

Will this setup work?

Sorry for the bad picture.


kingster996 - 17/2/15 at 12:36 PM

Interesting topic - Dunnell sell blanking plates - I guess they know a thing or two?

linky


lsdweb - 17/2/15 at 12:53 PM

When I put my Zetec together a good few years ago, I phoned Dunnells up to ask if they sold a crank case breather (as I had a bare engine). Their advice was to blank it up. I'm not looking for an argument btw!!


40inches - 17/2/15 at 01:05 PM

quote:
Originally posted by lsdweb
When I put my Zetec together a good few years ago, I phoned Dunnells up to ask if they sold a crank case breather (as I had a bare engine). Their advice was to blank it up. I'm not looking for an argument btw!!


Had a few thoughts about this myself. The breather/oil separator on the Duratec(v6) is in the head valley and the outlet pipe runs to a check valve that only opens when there is vacuum in the inlet manifold. So under any load the crank can't breathe?
On the Jag the rubber outlet hose breaks down and effectively seals the breather off, there is no effect on the engine until the vacuum
makes a hole in the rubber, then the tick over gets a bit lumpy, but that's all.


Paul Turner - 17/2/15 at 01:36 PM

quote:
Originally posted by lsdweb
When I put my Zetec together a good few years ago, I phoned Dunnells up to ask if they sold a crank case breather (as I had a bare engine). Their advice was to blank it up. I'm not looking for an argument btw!!


But Dunnell is an ignorant time wasting idiot (unless you have spent £1000's with him). Told he is still nice and helpful providing you want to spend £1000's more.

[Edited on 17/2/15 by Paul Turner]


r1_pete - 17/2/15 at 02:45 PM

6 years or so ago I blanked the crankcase breather on the Zetec I fitted into my MGB, and just vented the cam cover via a small K&N, had no problems at all, and neither has the new owner after 40,000 miles.

My theory is that the windage tray is in there to stop the oil foaming in the zetec, the crossflow and the likes do not have the tray, and hence as the oil foams it is more susceptible to heat, fuming, and being forced out of the breather, maybe a complete LOB, but there you go.


Paul Turner - 17/2/15 at 03:07 PM

Ford build millions of engines and spend countless millions on research. If crankcase ventilation was not required they would save the few pence on parts and simply not fit it.

I appreciate that the emissions systems on our engines are different (basically non existent) but that does not mean you want the pressure in the crank case building up.

My car has been Zetec powered for about 14 years now and has always had the stock breather fitted with the valve removed and the pipe into a plastic bottle (together with a pipe from the cam cover breather). Its worked perfectly with virtually zero residue form either a well worn engine or new Blacktop.

Since all engines come with the breather (oil separator) box its easy enough to leave it fitted at zero cost. Just remember to remove the valve, it will not work without vacuum.


kingster996 - 17/2/15 at 04:30 PM

quote:
Originally posted by Paul Turner
Ford build millions of engines and spend countless millions on research. If crankcase ventilation was not required they would save the few pence on parts and simply not fit it.
More likely that this is specifically to meet emissions targets and regulations forced upon them - they have to fit it and they have to spend millions on R&D to keep an engine 'clean'. Doesn't mean the engine will suddenly fail if it is not there, simply that it will not pass the more stringent emissions standards that are actually not required for our particular cars.

[ETA] all in my opinion of course

[Edited on 17/2/15 by kingster996]


Rena - 18/2/15 at 09:08 AM

In Sweden we need to have the crankcase ventilation sealed/closed.

If i don´t plug the crankcase breather and use it, there are no connection on my inlet manifold to connect a hose as I´m running R1 carbs. The only inlet on my intake manifold is for brake servo. I have read that the PCV valve needs vacuum to open. Correct? Is there a replacement PCV valve that will be constant open?

I read somewhere that blanking the crankcase breather will be fine if using a dry sump.