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5EAT/ Torqueconverter gurus, please help!


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I will try to keep this as brief yet detailed as I can:


Car: 2005 Legacy GT Automatic, 5EAT


History: Swapping in long block from 2008 WRX manual. Did not use Subaru Tool to hold Torque Converter (TC) assembly (works by hooking onto ring gear and bolting to starter mount hole if you do not know what I am talking about).


Motor was hard to separate from transmission but when it finally did, the TC stayed in the bellhousing (on the tranny side).


During assembly, in my folly I assumed the TC was just fine where it was, did not realize that all that wiggling may have unseated TC. Made common error of trying to mate engine to transmission with an improperly seated TC (I see this is a common shadetree mechanic mistake in google searches). Done a few R&R of transmissions and engines, but never with automatic, and never with subaru.


Took a lot of effort to get the motor even close but motor would not seat for the last 3/4 inch up to bell housing (of course).


I know better, but due to 4 hours sleep, time crunch, stifling heat and short temper, I was not thinking straight, and decided to use bellhousing bolts to "help" seat the bellhousing.


Went really slow, Gap closed a 1/4 inch, then heard pop sound coming from TC area. Stopped right away.


15 minutes and a lot of cursing later, motor was back out to assess the damage.


Fished the oil pump tube out, luckily no damage to tube nor tabs that interlock with oil pump. Circlip slightly bent but bent it back and now it clips in fine


Removed (and replaced with new) torque converter seal, while seal was out I shone a light down into the hole and looked that the area where the oil pump tube interfaces with oil pump, saw no damage but don't know if anything behind that area is damaged where I can't see. I hope my oil pump is not damaged...


checked TC, tube flange that connects with oil pump tube has no damage on it.


There are 2 things that worry me and this is where I need expert help:


1) inside the TC (looking down the hole) there are 2 sets of female splines. The deeper, smaller diameter one has no play as far as I can tell (hard to get my fingers down that far) BUT the shallower, wider diameter splines (for the stator I believe) had a lot of play, like 1/4" each way is my guess, and when I wiggle it around it makes a "thwock" sound as it hits something inside the TC. It is not so loose that it rattles if I shake it (mind you the TC is still full of fluid) just that I can move it around inside with my fingers. Google search shows one person also having this issue (which was never resolved on the forum) and another saying he bought another TC because of this, and the new TC was tight. Is my TC fubared?


2) The input shaft coming out of the tranny (central smaller diameter spined shaft that rides inside a larger diameter splined shaft) only protrudes out past the edge of the larger shaft by 42 mm. The FSM I have specs it at 50-55 mm. It still spins by hand (requiring decent force to twist, similar to turning an assembled RWD diff by hand) and I can't hear any noise or roughness when turning the shaft, but the 42 mm protrusion concerns me. Closest thing I could find by searching yielded a post where a person with a 4EAT had jammed his input shaft in, and a Subaru technitian said that shaft should be removable by hand and easily re-inserted. My input shaft DOES NOT come out when I pull my hardest on it. Did I fubar my tranny?


I mounted the TC (with oil pump shaft) back on, and it seated really easy, almost too easy based on descriptions on the net. It just fell into place without the 3 steps that ppl usually describe. TC mounting flange was within spec distance to bellhousing face (under 8 mm is spec, was like 4 mm). Span TC around both ways and it span smoothly, no sounds, but no oil coming out of trans fluid cooling line like I thought there might be. I can confirm that oil pump tube was engaged because when I pulled the TC off, the tube tabs were lined up with the oil pump slots.


Any help is appreciated, it's taken me many hours to get this far, it would be heartbreaking to find out I damaged something with my mistake, but I rather find out now with the motor out than find out the hard way later.


Thanks in advance!

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After talking with a transmission shop, I went ahead and tested the components myself to the best of my ability.


-I manually rotated the oil pump with 2 long sticks inserted into the drive slots. Rotated smoothly with no sound in both directions. Good indication that oil pump is OK.


-Tested the TC after reading the following documents (very good info on TCs), especially good is the second link.






-TC seems fine, stator play in radial direction seems to be normal in other TCs of other makes, after all it sits on a fixed stator support shaft (larger diameter fixed shaft surrounding the input shaft) when properly seated.


-rotated stator splines by hand, putting pressure both in fore and aft directions and listened for crushed/broken components in the thrust and needle bearings, heard/felt none.


-Tested Stator clutch, and seems to function properly.


-Span TC turbine, spins smoothly. Saw some marks on spline ends of where it looks like it got marked up from when I forced the engine and tranny together. Hopefully this only is what caused the pop sound as the splines got forced into alignment...


-used White grease on stator support shaft and input shaft splines to check engagement depth when the TC is fully seated. Engagement depth on both shafts looks to be right up to where it was before (judging by existing wear marks on splines). This is good news, although the FSM specifies the input shaft should be sticking out more than it is on my tranny. Hope FSM is wrong or maybe I looked up the wrong section, like for the N/A tranny or something...


-verified on opposedforces.com that the 5EAT input shaft IS NOT removable by hand (doesn't look that way at all in parts diagrams available on that site), and that the 4EAT is of a totally different design that is splined on both ends, and DOES look removable.


-mounted everything back, now TC is fully seated, ready for round 2 of engine install.


So for the wayward traveller who may find this post, some tips I'd like to pass on:


-NEVER force your motor and tranny together. They are a bitch to line up (especially if you do not have an engine leveler and proper tranny jack), as the motor and tranny have to be in line, and the tranny bellhousing NEEDS to be jacked up or else the angle of motor entry will never clear the mount studs. BE PATIENT and get help if you can.


-Make sure that TC is seated! when properly seated the TC's mounting bosses (the ears that bolt up to the flexplate) are almost flush with the bellhousing flange surface, as in only a few millimeters away. People talk of feeling the TC seat in 3 steps, first step is feeling it slot into the oil pump, then into the stator support splines, then the input shaft splines. Mine felt like 2 steps, but is now seated nonetheless.


-The tranny MUST be jacked up in order to seat the TC! many people talk of spending 2 hours trying to seat the thing, and others (like me) seat it in a minute. What I suspect is happening is that the bellhousing is resting on the crossmember for those having trouble. The TC WILL NOT clear the crossmember if the trans is not jacked up at least an inch or two! it will not seat properly! it will ride up on the crossmember, through the cut out at the bottom of the bellhousing.


-coat the oil pump shaft and TC hub that it is connected to in ATF when inserting the TC and be gentle, also never let the shaft ride on the seal on the way in, you may damage the TC oil shaft seal, as well most likely jam the oil pump shaft up in the bore on the way in. Support the weight of the TC fully (I know, it's heavy) as you insert and seat it.


Hopefully someone finds this info helpful, it could prevent a very expensive and time consuming mistake!


As for me I hope everything is OK as I resume with putting my engine in. If I don't post back, either I was succesful and all is well, or I have pushed this car along with myself off a cliff in frustration.


Wish me luck!

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The torque converter center "nipple" will pop into the area of the flex plate on the crankshaft, thats probably what you heard. the flexible shaft that is on the other side of the TC has play in it, its suppose to, almost like an accordian of some sort. when removing my engine, i make sure to keep the TC seated to the tranny as firmly as possible as it has a "set" position, if it pulls out a 1/2" or so from the tranny input shaft, it may be cocked crooked and the tranny shouldnt be mated to the engine at this point.
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Good to know, thanks BMX045! when I pulled the motor back out, I did see some wear marks on that nipple that would correspond with what you said. Hope that is what I heard! If so that is good news
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