I have a 52 chrysler motor that I'm using wilcap adapter to utilize a 1978 torqueflite tranny. The problem I'm having is keeping the trans fluid in the transmission. I took out the car last week and it ran with proper shifting. Checked the fluid level in neutral and car running and it needed some fluid, so I added it and let it run a bit. During the week, the fluid I put in all leaked out of the transmission fill tube at the bottom where the tube sets into the tranny. I figured I overfilled it and got in and tried to drive it this weekend. The car would barely budge and didn't want to do anything. Wouldn't stay in gear and revs had to go relatively high to make it move. So I checked the level again, it was low, so I added two quarts. Get back in and it drive and shifts fine. Get the car home and let it be. This time I put a pan under the tranny fill tube. Sure enough, during the day today, about a quart leaks out again thru the fill tube area. I can't figure this out. It needs the fluid to run properly, but spits it out after sitting for 24 hours. Any ideas on what's happening here? Comments and discussion will be appreciated. Thanks.
It's been a long time since I have dealt with a 727, but if memory serves correct this is a common problem when the seal that seals the converter goes bad. It pumps the fluid into the converter, then when it sits, because the seal is allowing an air leak at the top, it drains the converter back into the pan. I had this happen with two transmissions, replaced the seals, got several more miles out of them and had it happen again. Finally solved it the best way I knew how- grew a third pedal, ripped out the 727 and replaced the whole mess with a Tremac 5 speed! No more leaks! Sorry, not much help with your problem, but I'd almost be willing to put money on it being that. Another quick thought though, how about a trans "stop leak" of some sort with a "seal conditioner" . Probably wouldn't hurt at this point.
Replace the tube O-ring, also check to see that fluid isn't coming out of the seal where the shift arm comes out. that seal has to be replaced by taking out the valve body i think.
This would be a good time to change fluid and filter and maybe find pcs of the o ring or the hole Oring thing in the pan. Get things good and clean and lube the new Oring.(SHAMLESS PLUG) Ive got a chrome pan for the 727 for $15.00+s..............YG
Actually the torqueflite drains the converter when in park(more accurately, it doesn't fill the converter fully), which is why the owner's manual states to run the trans through the gears and check the level in neutral. When it's in park, the fluid will show higher than in neutral. So if it's at the full mark in park, guess what-it's low when you're driving. My point is that the torqueflite drains the converter in park, and it shouldn't leak everywhere when it does. Check the o ring first, then tube roundness then for crack in casing around tube.
69Fury has it right. In order to remove the tube, just remove the bolt at the tab about half way up the tube and pull straight up. You don't have to remove the valve body. Lube the o-ring and tube when you reinstall it, work it in the case gently, its very easy to cut the o-ring. And I have NO idea what need louvers? is talking about. ALL trans converters drain back into the pan when not running. Don't bother with "seal fix in a bottle", its crap.
I agree with the others, it's your O-ring on the tube. You'll loose a bunch of fluid trying to do this, so you may a s well use it as an excuse to service the tranny. Then when it's empty you can easily swap out the O-ring.
Now that I understand the filling and draining of the torque converter, it makes sense as to why the oil pan fills up after running. The filler tube may need to be replaced since it might be out of round. I had to modify the midlength shape of it to fit into the 34 plymouth I put the motor in. The extended bell housing of the hemi moved it a few inches into the cabin. Perhaps I warped the bottom of it when I welded on the new piece. In any case, I did have a new o ring put on since the trans was rebuilt and I received a new one. I might have to double up on the o ring in order to get it to seal properly. I'm glad its not something more serious, as I thought it was. Thanks to everyone for their responses,
The shift shaft seal is what is likely bad. This seal will go bad over time, allowing the fluid to drain out that seal. Generally speaking, if the dipstick O-ring has not been disturbed, it is probably good. Do NOT double up on that dipstick O-ring, or it will leak. I've had the shift shaft seal go bad on several cars over the years. Each car would puke fluid on the floor. If you look carefully, the shift seal is on the driver's side, and the filler tube seal is on the passenger side. You will easily figure out which is bad, if you let the car sit overnight with some cardboard under it. The fix is to remove the valve body and then remove the shift mechanism, remove/replace the seal, and reassemble. Running with the problem isn't a big deal. Took me 15 years to get around to changing the one on my Coronet - just kept fluid in it!
Is it spraying fluid all under car during driving? do you have a tranny cooler on it,or just running the radiator cooler lines?whatever you do don"t double the oring,you probably need a new tube and you have to have a brace on the tube bolted securly or it will continue to give you problems.hope you haven"t hurt tranny with the high revs.
I have the same problem with one of my 727's, the one with the aftermarket fill tube. The stock fill tube never leaked, the aftermarket never stopped leaking. My fix will be this spring I am going to drain the tranny, remove the fill tube, thoroughly clean all mating parts, replace the o ring and silicone the pieces together
It has been my experience that when you mess with the fill tube this leaks happens .When installing the fill tube the o-ring needs to bottom out in the trans case. If you have changed the distance from the tab that holds the tube to the trans case bolt it probably is not pushing it down far enough into the housing.Make sure that this tab is bent enough to hold a slight amount of pressure on the tube. Best of luck
Yep! Common problem on a 727 trans (and probably every other AT too!). The O-rings on the dipstick tube get hard and don't seal when the torque converter drains back down. "Usually" the shift linkage doesn't leak where it comes out of the trans case, but rarely it will happen. You pretty much CAN'T double up on the O-ring. There's a small groove that the O-ring fits into and TWO definitely WON'T fit. I hear that if you try a SLIGHTLY larger O-ring that it'll help for cars that don't get driven as much, but I've never tried it. You'd have to find a THICKER one with the same ID but maybe a slightly larger OD... My $0.02 says that it's probably easier to just replace the old hard one with a new, softer one that is designed to be there!
I went to the shop that rebuilt the tranny and they repeated many of the comments noted in this thread. I was given a new O ring and it was suggested that I use a transmission oil rated gasket product and add a little around the O ring. Also, it was suggested that I consider installing a check valve in the return line from the remote trans cooler. They felt that keeping the fluid from returning to the trans case after use may help keep the transfluid lower in the dipstick tube and therefore keeping it from leaking out. If anyone has any idea what type of check valve could be used, it would be greatly appreciated. I believe my return lines are 5/16 lines. Thanks.
Some Dodge trucks use them in the tranny lines.They are usually connected in series using a clamped rubber section and a quick disconnect.Look up along the right frame rail where the lines run to the cooler.
I cured this by installing a deep trans pan. The deep pans come with a extended pickup, this allows you to run the level a little lower and keep the full mark below the tube. I used the add mark as the full. Van
Look on pages 127-128 http://www.mo-pod.com/pdf/09_Performance_Catalog-120908.pdf or, go here... http://www.monicattichrysler.com/comersus/store/comersus_viewItem.asp?idProduct=191 .
My both my 727s and one 904 tranny all did this. The torque converters all leak back after after sitting and if the O-rings are bad they leak. When you start it up it takes a minute to pump the converter back up. I just got used to having a drip pan under the truck in the garage. I am contemplating going to a T-5 or maybe TH-700R4 with adapter plate (AMC motor) as I'm tired of taking trannies in and out and still having them leak. Josh Quick Quick Speed Shop
The 727 and 904 are very reliable transmissions. Fix the two possible leak areas and they'll work forever. Two seals is all it takes.
I second that,its not going to leak if its done right.The idea of running lower fluid level in a auto trans is asking for a problem. Deep pans are not ment or sold for the reason of the tude o ring leak.This can be fixed in 15 min if you just do it .When you see it you will know its not a big deal........................YG
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