Diff breather manifold required?

Given that the breather valves on the diff etc are open ended, can someone explain why a manifold is needed on the end of the breather tubes?  For a cheaper solution couldnt the hoses be terminated in anything that prevents water splashing into hose?

Can breather tubes etc ever make things worse, such as if a hose disconnected, or got water in it?   I assume the factory valves are designed to prevent water build up at the opening, hence reducing the risk or water being drawn in when pressure drops. 

Jb74

To your first question, the manifold is not needed at all.
A lot of 4x4ers just use a length of hose, a small-engine type fuel filter, and a couple of jubilee clips or the equivalent to hold it together. The only reason to get a fancy manifold setup is if you are one of those nerds who likes festooning his Jimny with branded accessories. (Nobody like that here on the forum of course.)

As to the other question, yeah, if the hose came adrift that would be a problem. If you install remote diff breathers, make vent hose checks part of your PMs.

I fitted the Des Sol diff and TC breather kit to my Gen4 and yes it does feature a fancy manifold

 

However, the reason for fitting wasn’t the manifold but the quality of the fittings used to clamp over the existing breathers, which feature 90 degree pipe fitting, o-ring seal and 2x grub screw.  The clamps also feature spring loaded push fit pipe clamps which are easy to use and provide a perfect seal on the tube, whilst allowing for easy repositioning.  They were very solid when fitted and I checked them after a few outings through water and hadn’t moved.

The transfer case breather would be very hard to fit without a 90 degree fitting as shown in the following photo

 

The Des Sol kit isn’t cheap, it’s about £100 in the UK, then with shipping, import duty and VAT they are about £150 and as Motacilla points out there are lots of lower cost options out there, but I was impressed with the breather clamps and the very clear step by step instructions.

Robin
 

GreyJimny wrote:

I assume the factory valves are designed to prevent water build up at the opening, hence reducing the risk or water being drawn in when pressure drops. 
 

The factory breather on a JB74 is a simple "one-way" valve with a downward facing vent - it allows air flow out of the vent, but not back in.  The problem that this, in theory, creates, is that it allows air in the axle housing to escape when it expands due to temperature rise of normal operation, but does not allow air to return when it contracts because of cooling.  This, theoretically, allows a vacuum to develop in the axle housing which can then draw water in past the oil seals, which are designed to keep oil in, rather than water out.

Theory says the water does not enter through the vent, but through the oil seals.

Suzuki has built vehicles with extended breathers from the factory (the 98~04 Grand Vitaras), and these are not fitted with a manifold or even a filter - a plastic cap that allows air flow in both directions but prevents debris from entering the line is what is used.  The front diff breather terminates near the top of the radiator, the rear diff breather terminates in the body cavity behind the left tail light, and the transmission & transfer case breathers are "teed" together and terminate near the top center of the firewall.

Mine is zip tied on with one open port 
The open port used to have pipe up into snorkel head 
I no longer have a snorkel fitted 
Never had any issues with the open port

Thanks for the reply (and to others).

In regards to the hose coming off, Im a little confused whether this is any worse a situation compared to the stock breathers. Are the stock breathers forced open during the install and hence loss of the hose is a serious problem, or are you saying Id just be driving like a stock Jimny again?

EDIT: I see that the factory valves are removed now that I have done more reading. Thanks anyway. 

Also, if I want to revert to factory setup, can the valves be put back on, or do I need to buy 3 (I have a manual) new ones? Approx cost?