Thread: Drain nipple - Defender 300Tdi - air filter

The air filter drain hole should have a 'flapper' valve, two pieces of rubber that suck shut whilst the engine is running (vacuum effect). That is supposed to stop water entering. When you turn off the engine any water trapped in the 'sump' of the valve can drain. I've had a safari snorkel fitted by ARB. They silicon sealed the drain hole in the intake hose in the engine bay and left the flapper valve on the air cleaner alone.

I was also a bit suspect, however, I've been through some deep (over the bonnet) water and inspected the air cleaner straight away and all was dry. I think if you stalled in deep water you would have to end up with a wet air filter. I suppose it's a toss up between a last defence against (it would have to be very heavy) rain getting sucked in through the snorkel or how often you play in deep water.

I suppose you could just duct tape it shut when going off road.

Are you talking about the evacuator valve on a Donaldson air cleaner? If so, it is an integral part of the air filtration system that uses intake pulses to expel dust and other unwanted particles that have been centrifugally separated from the incoming air. When wading deep water you may duct tape the valve closed but otherwise it is an essential part of the system.

I'm not sure Brian am I ? It's the standard thing where the air filter goes in the 300Tdi engione. Factory fitment.

My post was referring to the standard 300tdi air cleaner. The flapper valve is at the front and bottom of the canister where the cover is removed to access the air filter.

Also remember that there is an evacuator valve in the intake pipe between the mudguard and air cleaner housing on a 300Tdi.
This is often siliconed shut when running a snorkel as the air pressure from the snorkel may blow it open prematurely.

It's designed to drop any water that may be sucked into the stock intake rather than suck it into the air cleaner.

Or you could just do what I did and replace the entire length with some 80mm ID flexible duct to replace the ridiculous restriction of the 2" hose.
Cut the snorkel outlet back where it's 75mm OD instead of the 2" OD section so that the new duct fits the snorkel outlet.
It removes a huge restriction in the system, but it's probably only an advantage when running with the pump tweaked and a big exhaust.

ugu80 yeah thats where i mean. Its kind of like a cone cut in two halves on the long axis ?

This thread is interesting and no has me woried about the snorkle..

Defender 200 tdi Dump Valve - Whats the point? - Ford Forums - Mustang Forum, Ford Trucks and Cars

Those rubber boots perish after a few years and seem to stay open more than closed. Replacement is under $20, but a pain to fit without pulling the air box out.