automatic trans converter drain

[Charlie Chops 1940]

What causes the dreaded drain down of the converter?

I've been fighting the steady drip on a 700R4 that hasn't been used for a couple months. Thought it was about done- until I pulled the fill tube out...wrong again. It sure makes a mess.

No wonder I like hand grinders more and more.

Charlie

[wayne petty]

What causes the dreaded drain down of the converter?

I've been fighting the steady drip on a 700R4 that hasn't been used for a couple months. Thought it was about done- until I pulled the fill tube out...wrong again. It sure makes a mess.

No wonder I like hand grinders more and more.

Charlie

leaky seal on the input shaft...  not the torque converter seal.. loose bushing fits also can effect this.. where the input shaft turns inside the stator shaft. (hollow fixed splined shaft out the front pump)

http://www.s10forum.com/forum/f13/trick-for-teflon-seals-on-700r4-input-shaft-no-spendy-tools-477798/

i think there is one more seal farther out on the input shaft..


you do have an option... one of the mityvac  fluid evactuators...

http://www.autozone.com/autozone/accessories/Mityvac-1-9-gal-fluid-evacuator/_/N-26l7?itemIdentifier=594882_0_0_

stick it down the dipstick tune and suck the pan dry when you park it...  note how much you have extracted... pour it out of the evacuator into a container to pour back in..  after a 10 second start..then shut off..


will also come in very handy for other transmission filter services... imagine.. not spilling the ATF all over the place..

engine oil changes.. as you can use the thin dipstick tube suction tube and drain the pan from above.. .

not that i don't want you to pull the drain plug.. and the flushing action of the hot oil pouring out of the engine oil pan removes a lot of debris..

could also be very handy to remove any possible oil from used engines and transmissions .. or even rear ends..

or... if its clean... drop the suction tube into the radiator.. if its a side tank cross flow.. and pull the coolant out.. to reduce the volume you need to drain. thru the plug.. only handy on a few cars..

if you were not going to reuse the lower radiator hose.. you could punch a hole in it.. and stick the siphon tube and still get most of the engine coolant out..

[Charlie Chops 1940]

Thanks Wayne.

I don't know if I want to put the 700 back in if it gets removed, much less invest much in it.

I've got almost all the bits and pieces to slip a T-56 6 speed into this old girl while I'm at it.

Charlie

[Crosley.In.AZ]

Converter drain back involves all the parts at the front of the trans.  Pump parts, bushings, converter, input shaft...  

If the trans oil cooler is higher than the trans fluid level, the cooler can drain back too. You get a syphon happening.  Return line from cooler drains into the trans via the lube circuit. this pulls the oil from the converter thru the cooler system  and into the pan.