Torque converter question

I am having symptoms that pointed to a possible cracked flex plate.
I now have the transmission removed.
Flex plate looks ok, although if I place it on a flat surface it rocks. & the new one I bought has a slight gap between the plate & ring gear all the way around. The original has this only at three weld spots. Just throwing that out there in case it’s a problem….

Anyway, torque converter question -

if I spin the torque converter, it has one spot per rotation where i hear a scraping/rubbing noise & it gets hung up. Is this normal?

Also, I can rock the converter a little. Course it’s not bolted in, so not sure if this ok.

 

Nope. Re-seat it. Can be a PITA to seat fully. Some say 3 'clunks' should be heard when fully seating the TC. See my earlier post here - measure to be sure.

Regarding the flex plate to torque converter bolts - make sure to start with the black one FIRST.

 

No, if in doubt replace it. If the torque convertor is putting minute metal bits in the fluid it wont be long until the spool valves and shift solenoids start to hang. Drop the pan look at the filter screen and check for metal particles. It doesnt take much even a thread from a red shop rag will cause peoblems, the tolerances are that close. You can put an inline filter in the lines to the radiator and check it every weekend for a while to see if you caught it in time or not.

 

So reseating it means actually removing it? Or “just” pulling it forward?

I put “just” in quotes because most parts of this job have not been “just”, like just drop the tranny. Taking me what seems like forever & learning a lot though.

Story time - I had a ‘76 Nova & a big old thunderbird. The Nova was stuck in snow, so the ex decided to use the t-bird to push it. Whelp, somehow ended up with the t-bird under the Nova’s bumper & maybe stuck in the snow as well. Can’t recall. It was many moons ago. He R-D’ed the t-bird to where the trans would only go in reverse. When we (really it was he as I looked on in horror. All happened so fast.) got them untangled, I had to go in reverse around the block to get it to be in a good parking place. He said he would fix the t-bird & would say, “just need to drop the tranny. Only eight bolts.” Never did it. He was an ars in many ways…. Crashed my nova. Different story. I loved that car….

Anyway, so is the rocking normal? It’s actually clunking on one side.

& thanks for the bolt tip. I had them off once before trying to get a peak at the flex plate. When I went to reinstall them I did indeed start with the incorrect bolt & learned the lesson that way….

 

Yeah, as far as what I encountered, reseating means pulling it forward and then rotating and turning until you get it seated firmly. Here are two vids from YT which can be helpful. I suggest watching both and giving it a go.

https://youtu.be/coYEy7omLP4?si=Z0Cvqt0z0R7_wf9x

https://youtu.be/EtGIUIPE6ik?si=Cot5CT67j80WeheY&t=557

 

So you would actually replace it? I wish I could look at the screen. The transmission is on the jack right now....

 

Yes, replace TC, also that $25 seal behind it, drop pan and clean it also check magnets for heavy particulates (chunks). The filter, well it has the same micron count as a screen door so if its clean replacing it is your call. The most important thing is properly seating the TC on to trans shaft and keeping it there upon install (sometimes it can slide fwd during install process and get cocked) when i know the TC is properly seated ill rotate a bolt hole to 6 o’clock position then pack a terry cloth rag right below it between TC and bell housing to hold it in position while moving trans around for install. When i get within an inch of mating up gently slide the rag out. A motorcycle/ATV lift is very useful for remove install of transmission, R&R a transmission is so much fun....think about when you want to do it again, i did it twice in 12 months, yeah the $25 seal.
R/
Andy

 

One other thing… look at the torque convertor bolts too. I have heard stories regarding the “black” bolt and how it is supposed to be the first one installed. I install the bolts all finger tight first then torque them as opposed to install one and tighten, rotate to the next…

 

The black bolt is in fact different than the others. It is first as its design helps to align the tc to the fp.

 

@OLDHMECH61
@Glamisman
@Area51Runner
(I didn’t know how to quote after I posted, so I just tagged you all)


Ok. So I missed all this
Once I reseated it, it seemed ok unless I rocked it to one particular side & then it scraped…. sometimes. I guess I figured when it was smooth, it had found a happy place. There I go figuring on things I know nothing about. Shoulda, coulda, woulda come back here & asked….

Anyway, I’ve got the trans back in place (that was fun) & checked the tc spin & it spins freely until it hits one spot per rotation where I have to work harder to spin it. In other words, it gets hung up….

Soooo…. Just confirming. Replace. Aftermarket ok? Or reman?

Seal - gotcha. Guess this means I’ll have to back it all the way out. I had it back about 1 foot.

Would this tc issue cause the flex plate to warp? I had bought a new one & even though it wasn’t perfectly flat, I noticed the original was more off kilter….

 

Replace with a quality aftermarket. Build an A340 right now. Highly recommend Recon Torque converters Part #TO59.
List all needed torque converter dimensions to match up your old TC to the new one.

 

Other thing is I can’t say as I have symptoms of a bad tc.
I do have noises, hence the flex plate investigation. They sounded more like from the engine though, than the trans itself.
I do here a slight whining & rattle

no shifting problems, leaks, shuddering, vibes at 30-45 (I do have them at 75). No overheating that I know of (I don’t have a temp gauge), although the atf did look darker than I think it should have. Smelled a bit burnt as well. No junk in the fluid without checking the screen.

 

Couple of questions -
Does the center of the converter (turbine?), where the splines are, typically have a lot of play?

The flex plate - I could reinstall the original, however it did seem more warped than the new one. No cracks though & I could put the new one for sale on here. Opinions?

Also, this is what the inner bell housing looks like. Should I clean it up? The stuff Toyota put over the dust cover had worn away, so I imagine that’s how moisture got in…. Or it just does over time. I dunno.

 

Have you pulled the trans oil pan yet to see if you have metal? A new torque converter has about 1/8" of play side to side. I had a slight whine noise, ended up being a tab on the oil pump had broken off inside and was tearing up the oil pump gears. Root cause was from a worn out torque converter with too much end play adding additional wear. Could also tell by the bearing inside the input shaft support tube coming off the oil pump.

Your input shaft splines look worn or it could just be the focus of the picture.

 

I didn’t check the filter & right now I can’t because I have the trans on a jack.

 

Took some better pics

 

Yeah you definitely have some spline wear. At the minimum the torque converter is wobbling on the trans input shaft splines.

 

I am currently in a similar situation. Just replaced my flex plate, drove about 1,000 miles and I can hear that it broke again. Now I will admit I did not know about the black bolt deal until now. So Contemplating just replacing the TC and flex plate to hopefully not have to pull the dang thing off again.

 

You may already be aware of that there are other factors in a repeat offender flex plate. I can’t recall what they are though. That aside, amidst my mess, since I had not dropped the pan to start with, I ended up temporarily reinstalling the transmission & doing that. Found a bit of a mess. I removed the valve body & did the kit for that. Also cleaned up as much as I could without dismantling the transmission. Put the pan back on & replaced the torque converter since that was probably a mess as well. I’m now a pro transmission replacer…. (Three times for one job)
Anyway, not that this is much help to you. My flexplate was possibly ok, although it seemed a bit warped. I did replace it….
I am presuming your starter looked ok. I think that can cause flexplate issues, although I’m not sure if it will crack it.
You got a Toyota one, yes? I believe that’s important….
I ended up seeking the help of gearcruncher. He’s a transmission guru, to say the least. Also, there are threads on the repeat flexplate cracking….