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kirky2
10-03-2022, 01:07 PM
From a Brit having brought my baby back to U.K. a couple of years ago. Whilst sitting in garage over time a serious leak of transmission fluid (Fordomatic) develops and, as far as I can deduce, it is likely to be due to “drain back of fluid from torque converter into transmission housing” and thence via a route, as yet undetermined, onto the garage floor!
Would anybody know if it is possible to remove the transmission from the back of the engine of my 57 Skyliner without removing engine too. I have a 4 post lift facility.
Any advice on fixing this annoying issue with an otherwise well-behaved unit would also be most welcome.
Many Thanks. JK

oldave57
10-04-2022, 04:32 PM
Hello JK and welcome to the Ford family. Yes, it is possible to remove the Fordomatic transmission without removing the engine. In fact, the 57 Ford manual states that you cannot remove the engine and transmission together due to clearances in the engine compartment, so the transmission would need to be removed if you were planning to replace the engine (or at least disconnected and supported while you separated the engine).

I did this repair to my 57 Skyliner about 2 years ago and while difficult it is certainly doable, particularly if you have a 4 post lift. I did my work in my garage by placing blocking under all 4 wheels to get enough clearance to remove the transmission from under the car after removal from the engine.

You will first need to drain the transmission (by pulling out the dipstick tube and draining as much as possible) and then remove the driveshaft. The flex plate to torque converter mounting bolts are accessible through the lower front inspection plate on the bell housing, then rotating the engine to access the bolts. You can also drain the converter housing with two plugs on the front cover of the torque converter (although if yours is leaking it might not need to be drained.) The rear transmission mounting crossmember needs to be removed and transmission supported on a movable jack (transmission jack) and then can be moved rearward enough to clear the engine bell housing and lowered.

The most likely sources of your leaks are:
1) The large torque converter o'ring seal between the front cover and main housing.
2) The front pump oil seal and o'rings between the pump cover and pump to main housing.
3) The o'ring and lip seal for the transmission shift levers that protrude from the housing.
4) Transmission oil pan gasket.

Good luck with your project.
Dave

kirky2
10-13-2022, 09:45 AM
Thanks Dave - most helpful. One issue in the ‘box which I understand can develop is that the clearance between input shaft and support bearing enlarging over time so that the annular gap can allow more and more transmission fluid to run out of torque converter into into main casing, - ultimately until the oil level reaches the level of the shaft ie.9 o’clock - 3 o’clock level. As a ‘fix’ , I understand some American company offers a very thin-walled stainless steel sleeve to slip over the shaft and a new bearing - to bring clearances back to nominal. Any advice in this regard??? I’m not sure which of your likely sources (1) or (2), this relates to.
Thanks again.
JK

oldave57
10-17-2022, 09:03 PM
Hello JK,

I'm really not familiar with any such sleeve or where it would be installed. The most likely leakage from the torque converter to the outside (leakage from the bell housing) is the large o'ring seal (#1) and the front pump seal (#2). The torque converter assembly installs into the front pump and the front pump seal rides on the outside of the torque converter housing extension which engages (with tangs) to drive the front pump. There are also o'ring seals between the pump housing and the main transmission case that could leak to the outside. The torque converter is mounted directly to the crankshaft and flex plate and pilots directly into the crankshaft, so the converter rotates with the crankshaft and any movement of the converter would be related to the rear main bearing clearances.
Once you get into the transmission you might be able to see if there is unusual wear on the outside diameter of the converter extension that rides on the front pump lip seal.

Good Luck,
Dave

kirky2
10-30-2022, 03:32 PM
Hi Dave
After extensive searching I have found the note which I made several years ago (whilst staying in Florida with the Skyliner and the leak!) and it refers to 2 Rockauto parts mentioned under ‘1957 Ford Skyliner Auto transmission Fordomatic’ listing.
First is ‘Torque converter shaft seal 6988H and second is ‘Kwick Sleeve’ 99193. Both are Timken parts so I guess they are reputable in origin.’ Although it isn’t entirely clear that these parts will fix my problem, if you think this sounds a likely bet, I will go ahead and order these parts unless you are aware of any adverse comments from fellow club members. Whilst undergoing cosmetic bodywork fettling elsewhere over the winter, I will remove the autobox and seek to fix this otherwise well-behaved unit.
Many Thanks.

oldave57
11-03-2022, 09:50 PM
Hello JK,

I think the "Kwik Sleeve" and the seal are likely paired parts that would require installation together. The sleeve would address a potential worn sealing surface on torque converter housing extension that is sealed by the lip seal on the front pump housing. Your converter may indeed have a worn area on that area and so the pair of parts would need to be installed together. If your converter housing shaft extension is not worn, then the sleeve will likely still fit over the outside diameter to engage the seal that comes with the sleeve. The original seal might be too tight a fit on the sleeve, so I would say that ordering both parts would be a good idea. If you find that the converter extension does not have any wear and does not need the sleeve, you could order the original seal or use the sleeve and slightly oversized seal.

Good Luck,
Dave

kirky2
11-04-2022, 10:35 AM
Hi Dave
Thanks for the good advice. I will go ahead and order appropriate parts from Rockauto accordingly. And thanks for your patience in dealing with an old codger who doesn’t fully understand the working procedures of the Skyliner website and how best to use it. I have been advised by a friend that our discussions may have somehow been ‘private’ - this wasn’t my intention but merely caused by lack of familiarity with forum procedures. I guess my problem with the Fordomatic is not particularly rare and others may have encountered this issue themselves. If so, maybe there is a way of disseminating this conversation to other members for their perusal?
Thanks again
JK

kirky2
11-10-2022, 05:18 PM
Hi Dave
Just to say an unexpectedly rapid response from Rockauto to get me my lip seal, special flanged thin-walled sleeve and fitting cup here (UK) in 5 days from ordering. Very satisfactory. Hoping all will make sense when I open the gearbox.
Regards
JK

oldave57
11-11-2022, 07:08 PM
Hello JK,

That is indeed good service from the US to UK. I went to the Rockauto website and found the sleeve you ordered, but I'm afraid I cannot be of much assistance as to where that "cup sleeve" would go. It certainly looks like the converter cover hub that extends into the crankshaft/flex plate when the transmission is assembled to the bell housing to help align the converter when the converter cover is bolted to the flex plate. However that location does not require a seal since it is not exposed to oil. The opposite side of the converter has a hub extension that has two "tangs" that drive the front pump and the lip seal that inserts into the front pump seals on the outside diameter of this hub extension.

I hope the sleeve kit came with instructions that may be of help. I do believe that the sources of external leakage will be the large o'ring seal between the front cover of the converter and the main converter housing, the lip seal at the front pump that seals over the converter drive hub, the lip and o'ring seals for the transmission shift linkage and the rear output seal. I think it is normal for the converter to drain back into the main housing which is why it is necessary to run the engine when checking the transmission fluid level so that converter is filled by the running pump.

In any case, it will be quite an adventure to remove and inspect the components for wear and replace seals. I assume that you have the Fordomatic shop manual that gives fairly good instructions on the transmission disassembly and repair.

Good Luck,

Dave