M1078 front axle: under pressure when ctis is inflating? SOLVED

[Plasa]

Hello guys.
Sorry to bother you, but I have a question about ctis and the front axle.
I rebuild my front axle due ctis seals replacement. it should not be the reason, but now if I power on the ctis and the system is pressurized, the front axle and differential is also under pressure and air vents out from the vent plug. it takes around 10 minutes after ctis stops that axle is at ambient pressure again.
Air came out from the small tube near the differential. What is strange is that I never hear air coming out from the vent plug behind the cabin.
It's normal?

Christian

 

[Ronmar]

Each hub has a vent line and those two tie together and back to the main/center axle housing. It is the inboard fitting on my axle. The T fitting is on the inside of the passenger frame rail on mine, you can use that fitting to determine which lines run to the vent ports on the hub. The other hose from the axle runs up to the vent. If y0u are not getting any air there, perhaps that wobble cap on the end is fouled, or the line is somehow kinked or damaged… Youshould be able to disconnect the vent line at the axle and blow air easily thru that line and out the vent cap… You could disconnect the hub vent lines at the hubs and see if the air is coming from one or both of the hubs. Sounds like at least one of the seals didn’t take…

 

[Plasa]

Thank you sir!
Indeed probably was the outside ctis seal leaking. Even if it was brand new it was 0,4mm larger than others. probably this was way too much to close when on pressure.
Tomorrow I will finish mounting the hub and let you know!
Thank you again!
Christian

 

[Plasa]

Thank to Ronmar I figured out that a CTIS seal (new one) for some reason was loosing air when under pressure. The ctis seals have 2 lips, one on each side. I measured the lip on the air side andit was 0.015 bigger than another spare seal. Remounted everything and now works again.
If you do a hub maintenance check before you install spider gears etc. your ctis. I mounted the wheel and ctis and only when no air is pushed though the bearing the seal is fine.

Christian

 

[coachgeo]

Thank to Ronmar I figured out that a CTIS seal (new one) for some reason was loosing air when under pressure. The ctis seals have 2 lips, one on each side. I measured the lip on the air side andit was 0.015 bigger than another spare seal. Remounted everything and now works again.
If you do a hub maintenance check before you install spider gears etc. your ctis. I mounted the wheel and ctis and only when no air is pushed though the bearing the seal is fine.

Christian

did you remount with new seal? flip the previous seal around so bigger was to inside.... orrrrrr??

 

[Plasa]

No, the direction of the seal was correct, the internal diameter was diffrent....

did you remount with new seal? flip the previous seal around so bigger was to inside.... orrrrrr??

 

[coachgeo]

No, the direction of the seal was correct, the internal diameter was diffrent....

you went with same seal still though? wonder if it was a manufacture change that made that one different.... hmmm......

 

[Plasa]

I bought them all from finditparts, single order, same sku no...
I will check the spare seals if there are some diffrences...

Christian

you went with same seal still though? wonder if it was a manufacture change that made that one different.... hmmm......