Duratec Breathing or not

[DiggerDave]

Hello All
Newbie to this forum

Recently purchased Escort fitted with Duratec 2.0 with dry sump, throttle bodies ex, you get the picture. But there is no breather fitted any wear on the engine it looks to be all sealed up tight. I also think its breathing though the oil tank in the boot as it slowly fills up the overflow catch tank. Engine runs great but does not pull as hard as I expected dynode at 275bhp.

So engine breather or not? feedback.

Digger Dave

[DiggerDave]

I managed to find the answers on a UK forum I use see link, explained very well.

http://www.burtonpower.com/tuning-guide ... ystem.html

[Danny M]

The reason you can get by with that system is the pommie pumps are so small and inefficient they don't pull much volume be it positive or negative pressure. So you have very little fear of the engine being sealed and sucking in the seals. If you were using an American pump they will suck the seals in giving you a loud chirping noise. The best system especially with an American pump is to run a 3rd -10AN breather line to the tank with a one way flapper valve so it will allow the pump to pull some negative pressure but when the rings flutter or they're getting warn it will allow the positive pressure in the crankcase to vent to the tank.
If you engine is not making the numbers which I would expect and if the engine is breathing you need to do a leak down test to start withto give yo uan idea on condtion

[durescort]

I agree with all that. I also use a decent Peterson pump and as a safety precaution to protect the seals, I fitted a vacuum control valve to the crankcase breather to limit the max CC vacuum to 19 "Hg. at the same time putting the one-way flapper valve off the valve cover (I used a brake booster one-way valve) so in the event that you have a major blow-by issue/blow-up it can still breathe easily back to the catch can.

[ratta tat tat]

I just read that Burton guide. Regarding performance applications, if the cam cover has an internal deflector plate (like the pinto does), what's the point in running a hose from the filler cap to the catch can? Is there any reason why you couldn't just use a breather cap without a barb on it? It all gets vented to atmosphere anyway whether it be via the filler cap or at the catch can