I searched and found a few threads about fitting breathers to the ML and MN and there's bits and pieces of info in the group buy thread and around the place.
I am hoping we can keep this thread purely for info on fitting the breather extensions
This is how I fitted my kit to my 07 ML, its a V6 auto.
I started by working out where I was going to fit the alloy housing in the engine compartment. Up the back inner mudguard on the passenger side, mine had a relay that was bolted to the inner guard. I moved the relay and mounted the block there. See pics further down.
I started at the rear diff. The factory breather tube runs from the top of the diff centre up to the cross member. Its a flexy black pipe as can be seen here in the pic
Undo the clip holding the pipe to the cross member and fit this barbed fitting into the end of the pipe like this
then zip tie the pipe back up to the passenger side chassis rail like this. Leave plenty of slack in the pipe for offroading when the vehicle articulates
then run the new pipe up the chassis rail to the engine bay, zip tieing as you go.
next was the front diff and you will need to remove the bash plates to do this. There's only 7 12mm bolts holding them on and they are easy to find.
On my 07 ML, the diff centre is vented to the firewall. Follow the pipe up to the firewall so you know where it goes. Make sure you trace the right pipe. If you hook into the wrong pipe, you will not be able to engage the front diff as the vaccuum pipes used for this run along with the breather pipe
this is the top of mine
under that black rubber top, the end is flared and you wont be able to push the breather pipe over it. I went back down the pipe to where a flexy pipe joins a hard pipe, its near the chassis rail and pulled the flexy pipe off and then pushed the extension tube over the metal pipe. Its a tight fit and wont come off. here's a pic, its the pipe in the bottom left corner of the pic
then run the pipe up the firewall and across the top of the engine bay to the breather block.
Next was the transfer case breather. You will need to remove the centre console to get to it (unless you have a hoist and hands like a 6 year old child
). To remove the console, remove the two 10mm bolts in the console bin, pull the section containing the rear window switch and ciggy lighter out (it just pops out if you pull it forward at the top). Then lift the rear console section up and forward over the handbrake lever. Then you will find two 10mm bolts holding the rear of the front console piece. Take them out.
If you have an auto, you will need to take the gear selector off. Pull the gear lever down to Low (make sure the handbrake is still on! or you will roll down the driveway - not a good look with SWMBO observing from the lounge window
)
Take the two grub screws out of the base of the lever and pull it up. There are 2 small cables that run up the inside of the gear lever for the overdrive switch. These cables are not very long, trust me, I found out the hard way and broke them off the back of the switch. So pull the lever up as far as you can without breaking the cables and then poke a small flat screwdriver up into lever and push the selector rod down. This will let you pull the lever off safely.
The transfer lever knob just winds off as would the manual gear lever knob.
The forward console will now lift off easily.
The transfer lever has another boot over it which is simply screwed down with half a dozen screws. Take the screws out and pull the boot up and over the lever, it wont come all the way off and you dont need to anyway.
Once this is up, you will see that there is a small brassy coloured pipe that runs into the front of the boot that goes over the selector.
Pull the brass pipe out. It only goes into the boot and stops, it doesnt go into the transfer case or anything like that. Ths brassy coloured pipe comes from the gearbox (thanks ag9111) and vents into the transfer case boot. I pushed an extension pipe onto the end of the brassy coloured pipe and also poked another into the rubber boot like in the pic. Then run these extension pipes behind the heat shield and up into the engine bay, across the firewall like the front diff extension and to the filter block.
The clearance in the gearbox tunnel is almost nil and no one yet has been able to locate any other breather outlets for the gearbox and transmission. So this is part of the install is based on what information is currently available from forum members. If you can find alternate breathers on the transfer case and transmission, please post up their locations.
Once you have the pipes over near the vent block, simply push the pipes into the fittings. If you need to get the pipe back out, just depress the blue fitting and the pipe will slide back out
this is where I fitted my vent block
you will see that the vent block has 4 outlet pipes. Its important to put a pipe into each outlet as leaving one 'empty' will compromise the filter system.
all up it took me about 2 hours (mind you I wasted half an hour fiddling with the damn auto lever).
This is only for the ML auto. I havent seen the manual box breather set up nor a MN, so if you have pics and info on these ones, please add them here for the benefit of everyone.
Now I can go plunging into waist high water