Diff Breather check?

Joined
Jun 9, 2003
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Mesa, Arizona
 
 
 
Now that I am almost done with my birf job, I really want to make sure that my diff breathers are venting properly. How can I do that? How are they supposed to work?

Jared
 
Joined
Nov 16, 2003
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Dixie co. Florida
 
one way is to drain fluid with the fill port closed (crack open the fill first just in cast it is suck then close ti again) if the fluid comes out "goes glug glug glug...." as it alternately flows oil out then air back in then the breather still has the OEM evil little flapper or is otherwise plugged, if it pours out smoothly in a steady stream then the breather is breathing.

also if you hear air rushing in when you open the fiil port then it still has the flappers.
 
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Chandler, AZ
 
 
The best way IMHO is to get about 12' of 1/4" fuel line and a couple of little plastic fuel filters and disconnect the factory lines and run new lines to the master cylinder area in the front and into the jack cavity near the fuel filler in the rear, capping both with the filters. :D
 
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Thanks Kevin, but that would be a way to replace your vent line. I just wanted to know how to find out if that little vent cap thingy was working, or if the system was clogged.

Isn't there a way? Or are you really better off just replacing the thing?

Jared

PS-- Kevin--- do you have a picture showing where and how you ended your new vent lines?
 

NorCalDoug

problems solved daily...
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Oct 27, 2003
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uhhhh...duh...Northern CA
 
 
 
Jared,
I'd just extend them like Kevin stated.

I have my front and rear breather lines connected with a "T" to a common line that terminates in my engine compartment. I capped the top with an inexpensive fuel filter.

It's easy to do and you'll essentially be killing two birds with one stone -- you'll have extended diff breather lines and you'll know that your new lines will be vented properly.
 
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sjpitts said:
PS-- Kevin--- do you have a picture showing where and how you ended your new vent lines?
Nope, it was way simple, just ran them up as high as possible, held them in place with zip-ties and capped them with fuel filters.
 
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It looks to me like CDAN is still using the stock vent-cap on his extended breather.

OTOH, Kevin says he just used filter.

Which is the better approach? And again, does any body know how those vent caps are supposed to work, and how you can confirm they are working?????

Jared
 
Joined
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Messages
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sjpitts said:
It looks to me like CDAN is still using the stock vent-cap on his extended breather.

OTOH, Kevin says he just used filter.

Which is the better approach? And again, does any body know how those vent caps are supposed to work, and how you can confirm they are working?????

Jared
The stock breather is a one way valve, allows air out but not in, at first glance this looks good, you don't want to pull dirt/muck/water into the diff right? So your cruising and the diffs are up to operating temp, then submerge them. The water rapidly cools the diff causing a vacuum in the housing, the stock breather holds the vacuum so any little leak in the housing pulls in water, also blamed for pulling grease from the birf housing into the gear oil. With a free flowing filtered breather the diff is always at the same pressure as the surrounding air. Some people who play in water often use a small compressor to keep the diff housings at a slight positive pressure, driving out water when submerged.

Don't think there is a "right" way, when I installed the L shocks the stock breather lines were too short. So rather than spending anytime on the subpar stock system, I just replaced it, it was cheap, quick, easy and works, what's not to like? :D
 
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Jun 9, 2003
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749
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Mesa, Arizona
 
 
 
Tools R Us said:
The stock breather is a one way valve, allows air out but not in, at first glance this looks good, you don't want to pull dirt/muck/water into the diff right? So your cruising and the diffs are up to operating temp, then submerge them. The water rapidly cools the diff causing a vacuum in the housing, the stock breather holds the vacuum so any little leak in the housing pulls in water, also blamed for pulling grease from the birf housing into the gear oil. With a free flowing filtered breather the diff is always at the same pressure as the surrounding air. Some people who play in water often use a small compressor to keep the diff housings at a slight positive pressure, driving out water when submerged.

Don't think there is a "right" way, when I installed the L shocks the stock breather lines were too short. So rather than spending anytime on the subpar stock system, I just replaced it, it was cheap, quick, easy and works, what's not to like? :D

Ok, now I am convinced. That is a good explanation.

Thanks Kevin

Jared

/you still suck
 
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That's a hard way to do it. I did each end separately, the rear is routed from the diff along the fuel filler pipe to the left rear quarter, in along side the sunroof drain and up to the fuel cap area.

Going into the quarter.



At the fuel filler.



The front termination.

 
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