Race transmission breather - S/B 727

Jon Connolly · Post by **Jon Connolly** » Sat Jan 15, 11 8:45 pm

Am intending on running a small vent line from my transmission to allow it to " puke " up the tube instead of on the track.

Was planning on putting a catch can at a higher height than the trans vent outlet and putting a loop on the pipe just before going into the catch can.

My theory is this will act like a wet trap letting air out while letting fluid drain back down the tube into the transmission after a run so that the level always starts off correct

Anyone ???

Cannonball · Post by **Cannonball** » Sat Jan 15, 11 8:59 pm

some of the older gearboxes from late sixties early seventies had a breather high up on the trans like yours and it also had a little T off on the very top off the dipstick tube the pipe of the breather went up in the air high on the bulkhead and U turned back down on to the connection off the dip tube, and worked fine,
worth trying jon.
i just know that the 727 can breath heavy if really hot/pressured we useually put in to a jaz type catch can high on the bulkhead and check pretty regular

Jon Connolly · Post by **Jon Connolly** » Sat Jan 15, 11 9:00 pm

What provision do you make for letting the fluid return ?

or do you just manually top it up ??

Cannonball · Post by **Cannonball** » Sat Jan 15, 11 9:21 pm

Jon Connolly wrote:What provision do you make for letting the fluid return ?

or do you just manually top it up ??

drain jaz catch can and reuse if clean or top up through tube with fresh. set level on low mark running in neautral it will come higher on the stick after a pass,

Blue · Post by **Blue** » Sun Jan 16, 11 8:33 pm

What you can do is plug the vent in the front pump. Tap a new vent into the back of the transmission and run a line forward up the transmission tunnel into the bottom of a vented catch can high up on the firewall. That should allow any fluid that has puked out to gravity feed back into the transmission.

andyrob · Post by **andyrob** » Sun Jan 16, 11 8:41 pm

Jon,on my red roadrunner which used to be bad for puking until duncan moved the breather, I removed dipstick & had breather pipe pushed in the hole (but loosly so good breath)
Had no trouble for yrs like this

TrevD · Post by **TrevD** » Sun Jan 16, 11 9:13 pm

this is interesting, having never run a race trans i wasnt aware of this problem. where do they loose fluid from? top of filler tube????

Cannonball · Post by **Cannonball** » Sun Jan 16, 11 9:24 pm

Blue wrote:What you can do is plug the vent in the front pump. Tap a new vent into the back of the transmission and run a line forward up the transmission tunnel into the bottom of a vented catch can high up on the firewall. That should allow any fluid that has puked out to gravity feed back into the transmission.

that is what jon has had done blue,

Cannonball · Post by **Cannonball** » Sun Jan 16, 11 9:26 pm

TrevD wrote:this is interesting, having never run a race trans i wasnt aware of this problem. where do they loose fluid from? top of filler tube????

they puke out of a vent that is high in the pump body, the fluid then comes out the bellhsg and you can think your pump seal is blown or worse spray oil under your rear tires,

TrevD · Post by **TrevD** » Sun Jan 16, 11 9:43 pm

ok so looks like i need to talk to one of you guys to plug this and run a vent on the dart

Cannonball · Post by **Cannonball** » Sun Jan 16, 11 11:50 pm

TrevD wrote:ok so looks like i need to talk to one of you guys to plug this and run a vent on the dart

would be wise and blue is da man down your end,

Anonymous · Post by **Anonymous** » Thu Jan 20, 11 4:10 pm

The trans in my Volare had a Mega Puke in Kingston (not Jamaica) straight up the filler tube, then it caught light after spraying all over da Fanimold!

Guess what, I was no where near da Pod, actually was on the way there LOL!

Bac.