Has anyone ever run a one way check valve in their transmission cooler lines that prevents the fluid from draining back into the transpan after the vehicle has been turned off? This is a remedy that was suggested by a ****** shop when I told them about the fluid coming back out of the filler tube after operation. Obviously their first suggestion was to change the O ring, but that didn't solve the problem. Their second suggestion was to install the check valve in line on the trans cooler lines. They couldn't suggest a check valve for me to use. I have 5/16 cooler lines. Any suggestions or comments would be appreciated.
sure why not, it sounds good. but what about the return line wouldnt it just slowely drain through the return anyway.
you sure it aint just over filled.. and as the guy above me said..it will just seek the other line and come back in I think you got another problem..nothing that will be cured with this idea maybe you need to clean the dipstick gromet and hole real good and or, set a new dry gromet into a clean dry Dipstick hole dam that sounds harsh
which maker is the trans? most have an vent usually on top of the case,check to see if that is open.overfilling could do the same thing.i have done many trans overhauls and have never heard of installing a check valve in the return line?
Your cooler aint mounted real high is it? mine ussually have all sorts of fluid in them when i remove them and make a mess. A little ****** fluid on the ground looks like a lot. Is it comeing out the filler tube where you put it in? or around it at the base?
Agreed. I've seen several Chevys that would loose a lot of fluid if left for a week or two without running. The last one was a friends Blazer that I was putting floors/rockers etc on. Not a drop on the concrete for a week and a half...next night I had a pool 3' square to clean up!
Just replaced the transmission in my 1996 Dodge Ram and one thing everyone including a dodge chrysler transmission guru on the dodge truck org. said to do was remove the the OEM valve in the line. It is a restriction to the cooler that can get clogged.
Would one of you guys suggesting converter drain back please explain what causes it, I honestly never heard of it.
it's been said but check to make sure the vent is not clogged full of ****. especially if it is fresh rebuild!!!
Sorry Gents. I should have given more info. The ****** is a newly rebuild 727 torqueflite. I was told that the converter does drain back thru the return line of the trans cooler. The leak is taking place thru the fill tube fixture, going right past the new o ring that I installed. It was the ****** rebuilder that suggested the check valve to be placed in the return line. Thanks for your input.
My 727 with an aftermarket fill tube does the same thing. This spring I am going to drain the ******, clean all the oil off the fill tube and find a silicone or other sealer to seal the area. My other 727 with stock fill tube doesn't leak a drop
The converter is a large, hollow donut. It fills thru the center and centrifugal force keeps it completely full. Stop the rotation and it slowly drains back thru the center until it reaches the point where its level with the center hole. It takes some time due to the tight clearances and no vent in the converter for air to re-enter easily. The seal on the tube SHOULD be up to the task, but many are marginal enough to let the excess fluid get past. I'd try a new seal and factory tube along with some quality sealer.
some of the tri five guys have this problem with cast iron glides and install a one way valve in the return line I think to stop it--don't know if it works or not--I have a new one for that around here somewhere-will look at it-wife's 55 used to do this if it sat for more than a week without starting--bought the valve-put in a 700 instead Just looked at it--has directions to install in return line to prevent converter drainback--sold by cl***ic chevy--brand is REGO
That's a band-aid for the real issue. A cast aluminum part with a drilled hole (case) with a steel tube with an indent (fill tube) should be able to be sealed with an O-ring, even if normally under the fluid level when not running (it is). Drain the fluid and pull the pan. Clean the case and make sure the hole isn't wallowed out. Clean the tube and make sure it isn't cracked at the indent (common). Without the O-ring installed, check the filler tube in the case when it is mounted properly with the tab at the bellhousing. These are often bent or twisted. When right, the tube should fall squarely into the hole with even spacing all the way around. Adjust as necessary. Now, install the O-ring. Does it seat well in the indent and stick out evenly all the way around? Fix as needed. Maybe go up a size if worn or not sticking out. Now that everything is right, lube the O-ring and carefully install the tube. It should be fairly tough to get started. Shine a light from above and make sure it's sealing all the way around. Reinstall pan and fluid.
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