Hey everyone, I have a 2 speed Mile-O-Matic / Ford-O-Matic / Merc-O-Matic / Cruise-O-Matic from 1959. Just yesterday after running my engine, getting it hot, and running though the gears ford good measure, I noticed a small but steady leak coming from the rear of the transmission. I stopped the engine and investigated. I had just the from of the car on jack stands from this point. There was a good amount of fluid around the pan and its bolts, but it appeared to be coming from the reverse servo cover (driver's side servo cover) I wiped her down and decided to wait until today to see if anything else had seeped. Well, I get under there to look earlier and everything is pretty normal, not dry but nothing out of the usual for this tranny. Maybe just a little seepage from that serve cover. So I decide to jack up the rear end and run her in the air. I start her up and put her in reverse and I get a huge overflow out of the filler tube. I shut her off and wipe everything down / do a little online research / look in my Ford-O-Matic manual and see that causes of this are: aeration of the fluid; coolant in the fluid; and a blocked vent tube. Well, aeration I guess could be a factor. I did just recently do a complete fluid change on the tranny along with a complete empty of the torque converter. But I dunno. Coolant is a definite no because I have an external cooler. And blocked vent is maybe. I eventually did locate the vent tube and cleaned it up with a rag, seemed ok. So after all that, I start her up one last time, all while in the air, and let her run through reverse / drive/ neutral / low / and back to park. I don't get any more overflow through the tube, and that small but steady leak kinda disappeared. I'm going to do a little more investigation this weekend, but I wanted to throw that out there for now and get your guys opinions. Thanks in advance for the help everyone. Okay, update: I'm starting to think she IS overfilled. The real important thing is it seems my vent is not clogged, the trans overflows out the filler and the vent. Heres what happened. I started my engine, and immediately put the car into reverse, this spewed transmission fluid out of my filler tube. Keep in mind, she's cold at this point. I shut her off, wiped her down and started over. I left it in park and warmed the engine up to full operating temperature. While still in park, I noticed a leak occurring from the transmission vent. I stop the testing there. any insights? I want to add that I added an external transmission cooler, but other than that she' all stock and I'm pretty sure I went by the book in adding the quarts of fluid to the transmission. Maybe I screwed up, I dunno. Where should I go from here? On a side note, I tried to unscrew the vent, no luck. It doesn't have anywhere to put a wrench on it. I used a vice grip, but it just spins and spins. Here's a pic:
Us Old Guys called it Morning sickness. It's when overnight the converter drains back into the pan causing an over full condition in the pan and many leaks. Fluid level goes above the pan rail. The Wizzard
So I guess I'll drain out a quart tomorrow and see if that makes a difference. If I am getting drain back from the torque converter, does that mean the drain back valve is defective? If so, I'll have to drop the tranny to fix it right? I'll check cooler flow too
Correct, if that's the issue pulling the tranny is next. So first on a flat surface check the fluid level. The #1 sysptom is cold morning start up and drop in gear no movement. Also prior to start up check fluid level. Start motor and drop into Nuteral not park. After running a short bit drop in drive and all seems well. That's because you re filled the converter. If none of this applys to your car you probably just over filled it. A blocked cooler will not cause what you described nor a plugged vent. The Wizzard
Okay, update. I drained out a quart today. First, I started the engine and immediately put it into gear. I had a spotter and I was told the wheels started spinning immediately after it was put into gear. Also, no fill tube overflow that time. I ran everything until it was at operating temperature, and no leaks present. But now I am not getting a reading on my dipstick. Maybe it isn't original? I'll post a measurement in a bit.
You can try a longer dipstick and put into the tube. Note where the top of the tube to the dipstick is. When removing the longer dipstick note where the fluid registers. Then put it alongside the tube to make sure the dipstick end is at the pan level. Then compare with the original dipstick.
Looks like the measurement of my dipstick is 17 and 1/2 inches from the top of the riveted metal downward.
As d2 willys indicated the transmission is full when running when the level is at the pan rail; so if need be you could drop the pan and check your dipstick marking sighting across the transmission case were the pan bolts (pan rail).
It happened again today after a long hiatus... My tranny overflowed out of the fill tube. I was revving the engine (While cold) and it overflowed from the fill tube. Hasn't done this for a while. When hot, the dipstick shows the perfect level. Not sure why its overflowing. And yes its the correct dipstick. Maybe it has something to do with revving while cold?
Does anyone know... Since my vent tube is completely round with no accommodations for a wrench or a socket, how do I get that thing off?
If you can get a screw driver to it you can tap it out or some vice grips and turn and pull at the same time.
The vent is a thinwall with a light press fit. As saltflats stated, a Vise Grip (registered trademark) and a prying lever are the simplest tools. I mentioned 'registered trademark' on the Vise Grip, because the genuine article here works best. There are imitators that are inferior.
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