IWE vacuum system upgrades

[Squatting Dog]

So your saying keep one lline or as few connections as possible

---------- Post added at 11:49 PM ---------- Previous post was at 11:47 PM ----------



Would a small in line gas filter work or not ?

As few connections as possible. I am sure a small "briggs" inline could work. I rather spend a couple bucks extra for a filter designed for vacuum lines verse something that "might" work..

-Greg

 

[JP7]

Looks like I have my Saturday work outlined now. Or in-lined as it were...
I'm starting to think this was my problem with my 2010 and since I plan on keeping this one a little longer, and given my driving habits, preservation of the main 4wd components will be paramount...

 

[PropDr]

The only issue I see is unequal lengths of "vents" could cause driverside to lock faster than passenger side. Not sure if this would/could be an issue

You may have overlooked my edit:
Note: in a pneumatic control system vacuum vents are not located at the consumer/actuator but at the controller.

 

[Squatting Dog]

You may have overlooked my edit:
Note: in a pneumatic control system vacuum vents are not located at the consumer/actuator but at the controller.

So, the vent is at the controller. The issue is the unfiltered, exposed, or open tube from the IWE (intergrated wheel end). Leaving the IWE internals exposed to moisture and contamination during system cycling.

-Greg

 

[BigJ]

Before offering an opinion, I wanted to see where this vent line terminates on my rig but I can't find it under the hood. I traced right to where I think it is, but I didn't see any open to the air tube end.

Can you grab a picture Greg?

 

[Squatting Dog]

The exhaust/vent by front of upper control arm..

Driverside

View attachment 8856

Passenger side

View attachment 8857



-Greg

 

[pirate air]

You may have overlooked my edit:
Note: in a pneumatic control system vacuum vents are not located at the consumer/actuator but at the controller.

Depends on the actuator. A single acting pneumatic cylinder discharge vent port will most likely be found on the cylinder housing. The directional control valve could be as simple as a two envelope, two port, with no atmosphere/discharge port. Now a double acting pneumatic cylinder would vent at the directional control valve. The IWE actuator is much like a single acting pnuematic cylinder. Force from a spring is used to engage the locking ring and vacuum is applied to a diaphragm which forces disengagement. And from working on them I know for a fact the vent port is found on the IWE housing where a vacuum line is routed up to the chassis.



I wouldn't use the air box as the vent source. The air source isn't clean pre filter and the IWE is designed to use every bit of atmosphere pressure for clean engagement. Putting it in a semi vacuum area is asking for premature failure imo.

The hubs from the factory system don't engage at the exact same time. Depending on dog tooth ring position one may engage or disengage slightly faster than the other. Also wheel speed could be different if the vehicle is in a turn during transfer, causing different engagements speeds. So I wouldn't worry about different lengthes of tubing causing one to delay over the other.

Why not, skip rigid tube, and use flex hose for the whole route? That braided NHRA approved stuff is pretty damn tough. If something cuts that the 4x4 wouldn't be the only thing in need.

 

[Squatting Dog]

Depends on the actuator. A single acting pneumatic cylinder discharge vent port will most likely be found on the cylinder housing. The directional control valve could be as simple as a two envelope, two port, with no atmosphere/discharge port. Now a double acting pneumatic cylinder would vent at the directional control valve. The IWE actuator is much like a single acting pnuematic cylinder. Force from a spring is used to engage the locking ring and vacuum is applied to a diaphragm which forces disengagement. And from working on them I know for a fact the vent port is found on the IWE housing where a vacuum line is routed up to the chassis.



I wouldn't use the air box as the vent source. The air source isn't clean pre filter and the IWE is designed to use every bit of atmosphere pressure for clean engagement. Putting it in a semi vacuum area is asking for premature failure imo.

The hubs from the factory system don't engage at the exact same time. Depending on dog tooth ring position one may engage or disengage slightly faster than the other. Also wheel speed could be different if the vehicle is in a turn during transfer, causing different engagements speeds. So I wouldn't worry about different lengthes of tubing causing one to delay over the other.

Why not, skip rigid tube, and use flex hose for the whole route? That braided NHRA approved stuff is pretty damn tough. If something cuts that the 4x4 wouldn't be the only thing in need.

So, am I on the right track? Since the stock IWE system is vented to the atmosphere unfiltered. And the springs in the IWE actuators pull unfiltered air into the system.

Filtering the "vent" would help keep moisture and contaminates out of the system? Providing so longer longetivity out of notoriously failure prone IWE system?

Hard pipe looks nice, but seemless stainless steel lines are damn expensive. Flex is probably going to work a lot better..

-Greg

 

[BigJ]

Roger that Greg. Thanks.

I dunno. I see where you're coming from, but before I set out to make these changes, I'd want to ask the experts how many failures have they seen due to failed OEM lines (that weren't messed with otherwise)? How many IWEs have failed due to foreign material incursion/corrosion?

The official word on mine was that it was defective from the factory. If you believe that, and you keep in mind just how hard I beat on mine prior to that failure (lots and lots of desert time, a handful of water crossings, some beach/ocean time, etc) then that might be seen as a testament to how well the factory system works, after all.

I guess I'm wondering this: given the amount of work involved (not much, but some) AND the potential for new introduced issues with these changes, is it worth it? My (very limited) experience with "delicate" vacuum systems like this tells me they can be so sensitive that even a small change can bring the entire system down. Sucking thru a filter, for example, might require just enough vacuum over and above what is available, that you essentially have created a clog. What then?

Just thinking out loud Greg. I don't have any specific knowledge on this.

 

[pirate air]

So, am I on the right track? Since the stock IWE system is vented to the atmosphere unfiltered. And the springs in the IWE actuators pull unfiltered air into the system.

Filtering the "vent" would help keep moisture and contaminates out of the system? Providing so longer longetivity out of notoriously failure prone IWE system?

Hard pipe looks nice, but seemless stainless steel lines are damn expensive. Flex is probably going to work a lot better..

-Greg

Oh yeah, I'd say right track with a pre filter in a safe location under the hood somewhere. The open tube design ford used could deff benefit from a filter to keep dirt/dust/debris/water out. Water was always the number one problem I'd find. If the diaphragm stayed intact, the foreign material would only collect in the atmosphere side of the IWE. If the diaphragm broke, the foreign material could reach and ruin the solenoid control valve.



BigJ
The IWE system used to have problems left and right, due to stuff entering the system. I'd say the designs gotten better over the years, but it still happens. The pictures I posted up in the link to your thread was damage caused by water. We ended up doing both IWE's (iirc) on that truck due to water.