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A couple of basic 727 Questions

HawkRod

Formerly hsorman
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Some quick details:

73 Road Runner, 340 and 727, 3.55 rear. Car was a regular driver, and no issues with the transmission. Almost 4 years ago the 340 threw a rod out the block and I am now just putting the car back together. I have very limited time, but want to try to ensure the 727 works well.

Question #1:
There is evidence of a leak out the front of the transmission. Is this seal something fairly straight forward to replace (I have never rebuilt a transmission before)? Any advice here would be appreciated.
20210806_212620.jpg


Question #2:
The transmission has been indoors, drained of fluid, in my room temperature basement for 4 years. Can I simply fill with fresh fluid and put it back in? What is the likelihood of stuff slicking/ not working well? Any recommendations?

Thanks in advance for any advice and assistance. I know that the ideal thing would be to go through the transmission and refresh/ rebuild it, but I doubt I have time to learn how to do it in just a few days.

Again, thanks for the help!

Hawk
 
The seal is easy to change. Pop it out and put in the new one.

Do you have the converter that was in it? Is the snout in good shape? Does it have a drain plug and is it tight? Was the fluid spilled taking the converter out? Is that for sure ATF and not engine oil?

The trans will be fine because it was stored inside a heated room. Nothing will be sticking because it sat for 4 years inside.
 
Don't forget to put a little fluid on the seal where the converter rides on it.
I would pull the pan off and stick a new filter on it. Then you can check for metal and friction material at that time
I'll bet it's fine, they last a long time.
 
First thank you all for the rapid replies. I hope to do a lot of this today.

The seal is easy to change. Pop it out and put in the new one.

Do you have the converter that was in it? Is the snout in good shape? Does it have a drain plug and is it tight? Was the fluid spilled taking the converter out? Is that for sure ATF and not engine oil?

The trans will be fine because it was stored inside a heated room. Nothing will be sticking because it sat for 4 years inside.
Glad that storage will not have screwed it up. I will be using a much newer converter that came with another transmission and made for higher performance than the stock unit. Snout is in good shape on that one.

It is entirely possible much of the mess is from removal and when the engine threw a rod out the side of the block. I do have a faint memory of a very minimal transmission leak, and the dirty transmission seems to be some evidence of that. I'll see if I can get a seal today and try to replace it. If I can't, it shouldn't be a major problem.

Don't forget to put a little fluid on the seal where the converter rides on it.
I would pull the pan off and stick a new filter on it. Then you can check for metal and friction material at that time
I'll bet it's fine, they last a long time.
Good tip on the seal - thanks. I will pull the pan also to take a look. Hopefully it will be OK.

Also, set the bands, easy to do especially out of the car.
Great addition - I will do that. It has been awhile, but I have instructions somewhere on doing that and will try to refresh my memory. I think the last time I adjusted bands was in 1983!!!

Again, I appreciate all the help!
 
New front seal, fresh filter and pan gasket and run it.

ATF+4 if it was mine.
 
You should put a new shift selector seal on as well. With the trans out you can remove it with a drywall screw and pry it out.
 
ATF+4 if it was mine.
Is that the fully synthetic transmission fluid?

You should put a new shift selector seal on as well. With the trans out you can remove it with a drywall screw and pry it out.
OK. I'll see if I can get the seal quickly. I think the clock is rapidly running out. I may need to leave a few (possibly) weepy seals alone.

(They don't replace weepy seals on RoadKill!!!!! :poke: ) :lol:
 
The shift selector usually just leaks when sitting. It's not a problem while driving
 
Is that the fully synthetic transmission fluid?


OK. I'll see if I can get the seal quickly. I think the clock is rapidly running out. I may need to leave a few (possibly) weepy seals alone.

(They don't replace weepy seals on RoadKill!!!!! :poke: ) :lol:
No idea. More that likely it is. ATF+4 is Mopar spec fluid. Works well for me in old 727s too. You should be able to get a shift shaft seal at NAPA rather quickly.
 
I have had the thin seal on the outer edge of the pump housing dry out and leak. It looked a lot like your picture.
 
First, thank you for all the great replies. Here is an update on the transmission:

I pulled the pan and visually checked things out. The pan was super clean, with no particles of any kind, but with a little bit of greyish material that showed up on the rag when I wiped the pan out. I believe this is totally normal, so the transmission will get a new filter and pan gasket and it will run again!

All other transmissions I have seen have a thin metal plate over the vent that sits at the top of the pump housing. Mine did not (you can see it is missing on the first post). I removed one from another transmission I had laying around and bolted that on. Maybe that could contribute to some seepage?

Due to limited time, I decided not to replace the seals at this time. I know in an ideal world I should, but this tranny really didn't have any issues to speak of 4 years ago, and I have some other problems with my engine installation that I need to devote time to. I installed it on the engine (after lubricating the front seal and partially filling the torque converter).

I will still adjust the bands before the assembly goes back into the car and hope for the best! (If you like, you can follow along with my progress on my thread: https://www.forbbodiesonly.com/mopa...-hawk-rod-resurrection-roadkill-style.213411/ )

Gentlemen: Thanks for all the help!

Hawk
 
They changed the vent to a plastic piece and the plate won’t go on anymore. So if he was able to install one on his pump then it should be there.
 
Here is the newer pump with th plastic vent, you can see the round shape from the front so you can tell on an assembled trans.

44F67455-0AA8-4E0A-8024-49AF36958ED2.jpeg 526F00C1-DCEC-4515-BA6A-07EFCEE0A0D9.jpeg
 
Here is the newer pump with th plastic vent, you can see the round shape from the front so you can tell on an assembled trans.

View attachment 1150926 View attachment 1150927
Thanks. My transmission definitely did not have the plastic vent. I don't know if a transmission without the metal plate over the hole would seep slightly, but I'd rather have it on there. The engineers put it there for a reason!
 
It’s just so dirt won’t get inside, makes it go around corners with the plate. it won’t keep anything inside from coming out if it wants out
 
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